Update to pytest 3.2.5 (#6801)

* Update to pytest 3.2.5

* Get pytest to pass Python 2.6 compatibility checks

48 files changed, 3303 insertions, 2109 deletions

diff --git a/lib/spack/external/_pytest/AUTHORS b/lib/spack/external/_pytest/AUTHORS
deleted file mode 100644
index 8c7cb19cee..0000000000
--- a/lib/spack/external/_pytest/AUTHORS
+++ /dev/null
@@ -1,141 +0,0 @@
-Holger Krekel, holger at merlinux eu
-merlinux GmbH, Germany, office at merlinux eu
-
-Contributors include::
-
-Abdeali JK
-Abhijeet Kasurde
-Ahn Ki-Wook
-Alexei Kozlenok
-Anatoly Bubenkoff
-Andreas Zeidler
-Andrzej Ostrowski
-Andy Freeland
-Anthon van der Neut
-Antony Lee
-Armin Rigo
-Aron Curzon
-Aviv Palivoda
-Ben Webb
-Benjamin Peterson
-Bernard Pratz
-Bob Ippolito
-Brian Dorsey
-Brian Okken
-Brianna Laugher
-Bruno Oliveira
-Cal Leeming
-Carl Friedrich Bolz
-Charles Cloud
-Charnjit SiNGH (CCSJ)
-Chris Lamb
-Christian Boelsen
-Christian Theunert
-Christian Tismer
-Christopher Gilling
-Daniel Grana
-Daniel Hahler
-Daniel Nuri
-Daniel Wandschneider
-Danielle Jenkins
-Dave Hunt
-David Díaz-Barquero
-David Mohr
-David Vierra
-Diego Russo
-Dmitry Dygalo
-Duncan Betts
-Edison Gustavo Muenz
-Edoardo Batini
-Eduardo Schettino
-Elizaveta Shashkova
-Endre Galaczi
-Eric Hunsberger
-Eric Siegerman
-Erik M. Bray
-Feng Ma
-Florian Bruhin
-Floris Bruynooghe
-Gabriel Reis
-Georgy Dyuldin
-Graham Horler
-Greg Price
-Grig Gheorghiu
-Grigorii Eremeev (budulianin)
-Guido Wesdorp
-Harald Armin Massa
-Ian Bicking
-Jaap Broekhuizen
-Jan Balster
-Janne Vanhala
-Jason R. Coombs
-Javier Domingo Cansino
-Javier Romero
-John Towler
-Jon Sonesen
-Jordan Guymon
-Joshua Bronson
-Jurko Gospodnetić
-Justyna Janczyszyn
-Kale Kundert
-Katarzyna Jachim
-Kevin Cox
-Lee Kamentsky
-Lev Maximov
-Lukas Bednar
-Luke Murphy
-Maciek Fijalkowski
-Maho
-Marc Schlaich
-Marcin Bachry
-Mark Abramowitz
-Markus Unterwaditzer
-Martijn Faassen
-Martin K. Scherer
-Martin Prusse
-Mathieu Clabaut
-Matt Bachmann
-Matt Williams
-Matthias Hafner
-mbyt
-Michael Aquilina
-Michael Birtwell
-Michael Droettboom
-Michael Seifert
-Mike Lundy
-Ned Batchelder
-Neven Mundar
-Nicolas Delaby
-Oleg Pidsadnyi
-Oliver Bestwalter
-Omar Kohl
-Pieter Mulder
-Piotr Banaszkiewicz
-Punyashloka Biswal
-Quentin Pradet
-Ralf Schmitt
-Raphael Pierzina
-Raquel Alegre
-Roberto Polli
-Romain Dorgueil
-Roman Bolshakov
-Ronny Pfannschmidt
-Ross Lawley
-Russel Winder
-Ryan Wooden
-Samuele Pedroni
-Simon Gomizelj
-Stefan Farmbauer
-Stefan Zimmermann
-Stefano Taschini
-Steffen Allner
-Stephan Obermann
-Tareq Alayan
-Ted Xiao
-Thomas Grainger
-Tom Viner
-Trevor Bekolay
-Tyler Goodlet
-Vasily Kuznetsov
-Wouter van Ackooy
-Xuecong Liao
diff --git a/lib/spack/external/_pytest/LICENSE b/lib/spack/external/_pytest/LICENSE
deleted file mode 100644
index 9e27bd7841..0000000000
--- a/lib/spack/external/_pytest/LICENSE
+++ /dev/null
@@ -1,21 +0,0 @@
-The MIT License (MIT)
-
-Copyright (c) 2004-2016 Holger Krekel and others
-
-Permission is hereby granted, free of charge, to any person obtaining a copy of
-this software and associated documentation files (the "Software"), to deal in
-the Software without restriction, including without limitation the rights to
-use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
-of the Software, and to permit persons to whom the Software is furnished to do
-so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
diff --git a/lib/spack/external/_pytest/README.rst b/lib/spack/external/_pytest/README.rst
deleted file mode 100644
index d5650af655..0000000000
--- a/lib/spack/external/_pytest/README.rst
+++ /dev/null
@@ -1,102 +0,0 @@
-.. image:: http://docs.pytest.org/en/latest/_static/pytest1.png
-   :target: http://docs.pytest.org
-   :align: center
-   :alt: pytest
-
-------
-
-.. image:: https://img.shields.io/pypi/v/pytest.svg
-   :target: https://pypi.python.org/pypi/pytest
-.. image:: https://img.shields.io/pypi/pyversions/pytest.svg
-  :target: https://pypi.python.org/pypi/pytest
-.. image:: https://img.shields.io/coveralls/pytest-dev/pytest/master.svg
-   :target: https://coveralls.io/r/pytest-dev/pytest
-.. image:: https://travis-ci.org/pytest-dev/pytest.svg?branch=master
-    :target: https://travis-ci.org/pytest-dev/pytest
-.. image:: https://ci.appveyor.com/api/projects/status/mrgbjaua7t33pg6b?svg=true
-    :target: https://ci.appveyor.com/project/pytestbot/pytest
-
-The ``pytest`` framework makes it easy to write small tests, yet
-scales to support complex functional testing for applications and libraries.
-
-An example of a simple test:
-
-.. code-block:: python
-
-    # content of test_sample.py
-    def inc(x):
-        return x + 1
-
-    def test_answer():
-        assert inc(3) == 5
-
-
-To execute it::
-
-    $ pytest
-    ============================= test session starts =============================    
-    collected 1 items
-
-    test_sample.py F
-
-    ================================== FAILURES ===================================
-    _________________________________ test_answer _________________________________
-
-        def test_answer():
-    >       assert inc(3) == 5
-    E       assert 4 == 5
-    E        +  where 4 = inc(3)
-
-    test_sample.py:5: AssertionError
-    ========================== 1 failed in 0.04 seconds ===========================
-
-
-Due to ``pytest``'s detailed assertion introspection, only plain ``assert`` statements are used. See `getting-started <http://docs.pytest.org/en/latest/getting-started.html#our-first-test-run>`_ for more examples.
-
-
-Features
---------
-
-- Detailed info on failing `assert statements <http://docs.pytest.org/en/latest/assert.html>`_ (no need to remember ``self.assert*`` names);
-
-- `Auto-discovery
-  <http://docs.pytest.org/en/latest/goodpractices.html#python-test-discovery>`_
-  of test modules and functions;
-
-- `Modular fixtures <http://docs.pytest.org/en/latest/fixture.html>`_ for
-  managing small or parametrized long-lived test resources;
-
-- Can run `unittest <http://docs.pytest.org/en/latest/unittest.html>`_ (or trial),
-  `nose <http://docs.pytest.org/en/latest/nose.html>`_ test suites out of the box;
-
-- Python2.6+, Python3.3+, PyPy-2.3, Jython-2.5 (untested);
-
-- Rich plugin architecture, with over 150+ `external plugins <http://docs.pytest.org/en/latest/plugins.html#installing-external-plugins-searching>`_ and thriving community;
-
-
-Documentation
--------------
-
-For full documentation, including installation, tutorials and PDF documents, please see http://docs.pytest.org.
-
-
-Bugs/Requests
--------------
-
-Please use the `GitHub issue tracker <https://github.com/pytest-dev/pytest/issues>`_ to submit bugs or request features.
-
-
-Changelog
----------
-
-Consult the `Changelog <http://docs.pytest.org/en/latest/changelog.html>`__ page for fixes and enhancements of each version.
-
-
-License
--------
-
-Copyright Holger Krekel and others, 2004-2016.
-
-Distributed under the terms of the `MIT`_ license, pytest is free and open source software.
-
-.. _`MIT`: https://github.com/pytest-dev/pytest/blob/master/LICENSE
diff --git a/lib/spack/external/_pytest/__init__.py b/lib/spack/external/_pytest/__init__.py
index be20d3d41c..6e41f0504e 100644
--- a/lib/spack/external/_pytest/__init__.py
+++ b/lib/spack/external/_pytest/__init__.py
@@ -1,2 +1,8 @@
-#
-__version__ = '3.0.5'
+__all__ = ['__version__']
+
+try:
+    from ._version import version as __version__
+except ImportError:
+    # broken installation, we don't even try
+    # unknown only works because we do poor mans version compare
+    __version__ = 'unknown'
diff --git a/lib/spack/external/_pytest/_argcomplete.py b/lib/spack/external/_pytest/_argcomplete.py
index 3ab679d8be..965ec79513 100644
--- a/lib/spack/external/_pytest/_argcomplete.py
+++ b/lib/spack/external/_pytest/_argcomplete.py
@@ -57,26 +57,29 @@ If things do not work right away:
   which should throw a KeyError: 'COMPLINE' (which is properly set by the
   global argcomplete script).
 """
-
+from __future__ import absolute_import, division, print_function
 import sys
 import os
 from glob import glob
 
+
 class FastFilesCompleter:
     'Fast file completer class'
+
     def __init__(self, directories=True):
         self.directories = directories
 
     def __call__(self, prefix, **kwargs):
         """only called on non option completions"""
-        if os.path.sep in prefix[1:]: #
+        if os.path.sep in prefix[1:]:
             prefix_dir = len(os.path.dirname(prefix) + os.path.sep)
         else:
             prefix_dir = 0
         completion = []
         globbed = []
         if '*' not in prefix and '?' not in prefix:
-            if prefix[-1] == os.path.sep:  # we are on unix, otherwise no bash
+            # we are on unix, otherwise no bash
+            if not prefix or prefix[-1] == os.path.sep:
                 globbed.extend(glob(prefix + '.*'))
             prefix += '*'
         globbed.extend(glob(prefix))
@@ -96,7 +99,8 @@ if os.environ.get('_ARGCOMPLETE'):
     filescompleter = FastFilesCompleter()
 
     def try_argcomplete(parser):
-        argcomplete.autocomplete(parser)
+        argcomplete.autocomplete(parser, always_complete_options=False)
 else:
-    def try_argcomplete(parser): pass
+    def try_argcomplete(parser):
+        pass
     filescompleter = None
diff --git a/lib/spack/external/_pytest/_code/__init__.py b/lib/spack/external/_pytest/_code/__init__.py
index 3463c11eac..815c13b42c 100644
--- a/lib/spack/external/_pytest/_code/__init__.py
+++ b/lib/spack/external/_pytest/_code/__init__.py
@@ -1,4 +1,5 @@
 """ python inspection/code generation API """
+from __future__ import absolute_import, division, print_function
 from .code import Code  # noqa
 from .code import ExceptionInfo  # noqa
 from .code import Frame  # noqa
diff --git a/lib/spack/external/_pytest/_code/_py2traceback.py b/lib/spack/external/_pytest/_code/_py2traceback.py
index a830d9899a..5aacf0a428 100644
--- a/lib/spack/external/_pytest/_code/_py2traceback.py
+++ b/lib/spack/external/_pytest/_code/_py2traceback.py
@@ -2,8 +2,10 @@
 # CHANGES:
 # - some_str is replaced, trying to create unicode strings
 #
+from __future__ import absolute_import, division, print_function
 import types
 
+
 def format_exception_only(etype, value):
     """Format the exception part of a traceback.
 
@@ -29,7 +31,7 @@ def format_exception_only(etype, value):
     # would throw another exception and mask the original problem.
     if (isinstance(etype, BaseException) or
         isinstance(etype, types.InstanceType) or
-        etype is None or type(etype) is str):
+            etype is None or type(etype) is str):
         return [_format_final_exc_line(etype, value)]
 
     stype = etype.__name__
@@ -61,6 +63,7 @@ def format_exception_only(etype, value):
     lines.append(_format_final_exc_line(stype, value))
     return lines
 
+
 def _format_final_exc_line(etype, value):
     """Return a list of a single line -- normal case for format_exception_only"""
     valuestr = _some_str(value)
@@ -70,6 +73,7 @@ def _format_final_exc_line(etype, value):
         line = "%s: %s\n" % (etype, valuestr)
     return line
 
+
 def _some_str(value):
     try:
         return unicode(value)
diff --git a/lib/spack/external/_pytest/_code/code.py b/lib/spack/external/_pytest/_code/code.py
index 616d5c4313..f3b7eedfce 100644
--- a/lib/spack/external/_pytest/_code/code.py
+++ b/lib/spack/external/_pytest/_code/code.py
@@ -1,14 +1,16 @@
+from __future__ import absolute_import, division, print_function
 import sys
 from inspect import CO_VARARGS, CO_VARKEYWORDS
 import re
 from weakref import ref
+from _pytest.compat import _PY2, _PY3, PY35, safe_str
 
 import py
 builtin_repr = repr
 
 reprlib = py.builtin._tryimport('repr', 'reprlib')
 
-if sys.version_info[0] >= 3:
+if _PY3:
     from traceback import format_exception_only
 else:
     from ._py2traceback import format_exception_only
@@ -16,6 +18,7 @@ else:
 
 class Code(object):
     """ wrapper around Python code objects """
+
     def __init__(self, rawcode):
         if not hasattr(rawcode, "co_filename"):
             rawcode = getrawcode(rawcode)
@@ -24,7 +27,7 @@ class Code(object):
             self.firstlineno = rawcode.co_firstlineno - 1
             self.name = rawcode.co_name
         except AttributeError:
-            raise TypeError("not a code object: %r" %(rawcode,))
+            raise TypeError("not a code object: %r" % (rawcode,))
         self.raw = rawcode
 
     def __eq__(self, other):
@@ -80,6 +83,7 @@ class Code(object):
             argcount += raw.co_flags & CO_VARKEYWORDS
         return raw.co_varnames[:argcount]
 
+
 class Frame(object):
     """Wrapper around a Python frame holding f_locals and f_globals
     in which expressions can be evaluated."""
@@ -117,7 +121,7 @@ class Frame(object):
         """
         f_locals = self.f_locals.copy()
         f_locals.update(vars)
-        py.builtin.exec_(code, self.f_globals, f_locals )
+        py.builtin.exec_(code, self.f_globals, f_locals)
 
     def repr(self, object):
         """ return a 'safe' (non-recursive, one-line) string repr for 'object'
@@ -141,6 +145,7 @@ class Frame(object):
                 pass     # this can occur when using Psyco
         return retval
 
+
 class TracebackEntry(object):
     """ a single entry in a traceback """
 
@@ -166,7 +171,7 @@ class TracebackEntry(object):
         return self.lineno - self.frame.code.firstlineno
 
     def __repr__(self):
-        return "<TracebackEntry %s:%d>" %(self.frame.code.path, self.lineno+1)
+        return "<TracebackEntry %s:%d>" % (self.frame.code.path, self.lineno + 1)
 
     @property
     def statement(self):
@@ -245,19 +250,21 @@ class TracebackEntry(object):
             line = str(self.statement).lstrip()
         except KeyboardInterrupt:
             raise
-        except:
+        except:  # noqa
             line = "???"
-        return "  File %r:%d in %s\n  %s\n" %(fn, self.lineno+1, name, line)
+        return "  File %r:%d in %s\n  %s\n" % (fn, self.lineno + 1, name, line)
 
     def name(self):
         return self.frame.code.raw.co_name
     name = property(name, None, None, "co_name of underlaying code")
 
+
 class Traceback(list):
     """ Traceback objects encapsulate and offer higher level
         access to Traceback entries.
     """
     Entry = TracebackEntry
+
     def __init__(self, tb, excinfo=None):
         """ initialize from given python traceback object and ExceptionInfo """
         self._excinfo = excinfo
@@ -287,7 +294,7 @@ class Traceback(list):
                 (excludepath is None or not hasattr(codepath, 'relto') or
                  not codepath.relto(excludepath)) and
                 (lineno is None or x.lineno == lineno) and
-                (firstlineno is None or x.frame.code.firstlineno == firstlineno)):
+                    (firstlineno is None or x.frame.code.firstlineno == firstlineno)):
                 return Traceback(x._rawentry, self._excinfo)
         return self
 
@@ -313,7 +320,7 @@ class Traceback(list):
         """ return last non-hidden traceback entry that lead
         to the exception of a traceback.
         """
-        for i in range(-1, -len(self)-1, -1):
+        for i in range(-1, -len(self) - 1, -1):
             entry = self[i]
             if not entry.ishidden():
                 return entry
@@ -328,30 +335,33 @@ class Traceback(list):
             # id for the code.raw is needed to work around
             # the strange metaprogramming in the decorator lib from pypi
             # which generates code objects that have hash/value equality
-            #XXX needs a test
+            # XXX needs a test
             key = entry.frame.code.path, id(entry.frame.code.raw), entry.lineno
-            #print "checking for recursion at", key
-            l = cache.setdefault(key, [])
-            if l:
+            # print "checking for recursion at", key
+            values = cache.setdefault(key, [])
+            if values:
                 f = entry.frame
                 loc = f.f_locals
-                for otherloc in l:
+                for otherloc in values:
                     if f.is_true(f.eval(co_equal,
-                        __recursioncache_locals_1=loc,
-                        __recursioncache_locals_2=otherloc)):
+                                        __recursioncache_locals_1=loc,
+                                        __recursioncache_locals_2=otherloc)):
                         return i
-            l.append(entry.frame.f_locals)
+            values.append(entry.frame.f_locals)
         return None
 
 
 co_equal = compile('__recursioncache_locals_1 == __recursioncache_locals_2',
                    '?', 'eval')
 
+
 class ExceptionInfo(object):
     """ wraps sys.exc_info() objects and offers
         help for navigating the traceback.
     """
     _striptext = ''
+    _assert_start_repr = "AssertionError(u\'assert " if _PY2 else "AssertionError(\'assert "
+
     def __init__(self, tup=None, exprinfo=None):
         import _pytest._code
         if tup is None:
@@ -359,8 +369,8 @@ class ExceptionInfo(object):
             if exprinfo is None and isinstance(tup[1], AssertionError):
                 exprinfo = getattr(tup[1], 'msg', None)
                 if exprinfo is None:
-                    exprinfo = py._builtin._totext(tup[1])
-                if exprinfo and exprinfo.startswith('assert '):
+                    exprinfo = py.io.saferepr(tup[1])
+                if exprinfo and exprinfo.startswith(self._assert_start_repr):
                     self._striptext = 'AssertionError: '
         self._excinfo = tup
         #: the exception class
@@ -401,10 +411,10 @@ class ExceptionInfo(object):
         exconly = self.exconly(tryshort=True)
         entry = self.traceback.getcrashentry()
         path, lineno = entry.frame.code.raw.co_filename, entry.lineno
-        return ReprFileLocation(path, lineno+1, exconly)
+        return ReprFileLocation(path, lineno + 1, exconly)
 
     def getrepr(self, showlocals=False, style="long",
-            abspath=False, tbfilter=True, funcargs=False):
+                abspath=False, tbfilter=True, funcargs=False):
         """ return str()able representation of this exception info.
             showlocals: show locals per traceback entry
             style: long|short|no|native traceback style
@@ -421,7 +431,7 @@ class ExceptionInfo(object):
                 )), self._getreprcrash())
 
         fmt = FormattedExcinfo(showlocals=showlocals, style=style,
-            abspath=abspath, tbfilter=tbfilter, funcargs=funcargs)
+                               abspath=abspath, tbfilter=tbfilter, funcargs=funcargs)
         return fmt.repr_excinfo(self)
 
     def __str__(self):
@@ -465,15 +475,15 @@ class FormattedExcinfo(object):
     def _getindent(self, source):
         # figure out indent for given source
         try:
-            s = str(source.getstatement(len(source)-1))
+            s = str(source.getstatement(len(source) - 1))
         except KeyboardInterrupt:
             raise
-        except:
+        except:  # noqa
             try:
                 s = str(source[-1])
             except KeyboardInterrupt:
                 raise
-            except:
+            except:  # noqa
                 return 0
         return 4 + (len(s) - len(s.lstrip()))
 
@@ -509,7 +519,7 @@ class FormattedExcinfo(object):
             for line in source.lines[:line_index]:
                 lines.append(space_prefix + line)
             lines.append(self.flow_marker + "   " + source.lines[line_index])
-            for line in source.lines[line_index+1:]:
+            for line in source.lines[line_index + 1:]:
                 lines.append(space_prefix + line)
         if excinfo is not None:
             indent = 4 if short else self._getindent(source)
@@ -542,10 +552,10 @@ class FormattedExcinfo(object):
                     # _repr() function, which is only reprlib.Repr in
                     # disguise, so is very configurable.
                     str_repr = self._saferepr(value)
-                    #if len(str_repr) < 70 or not isinstance(value,
+                    # if len(str_repr) < 70 or not isinstance(value,
                     #                            (list, tuple, dict)):
-                    lines.append("%-10s = %s" %(name, str_repr))
-                    #else:
+                    lines.append("%-10s = %s" % (name, str_repr))
+                    # else:
                     #    self._line("%-10s =\\" % (name,))
                     #    # XXX
                     #    py.std.pprint.pprint(value, stream=self.excinfowriter)
@@ -571,14 +581,14 @@ class FormattedExcinfo(object):
             s = self.get_source(source, line_index, excinfo, short=short)
             lines.extend(s)
             if short:
-                message = "in %s" %(entry.name)
+                message = "in %s" % (entry.name)
             else:
                 message = excinfo and excinfo.typename or ""
             path = self._makepath(entry.path)
-            filelocrepr = ReprFileLocation(path, entry.lineno+1, message)
+            filelocrepr = ReprFileLocation(path, entry.lineno + 1, message)
             localsrepr = None
             if not short:
-                localsrepr =  self.repr_locals(entry.locals)
+                localsrepr = self.repr_locals(entry.locals)
             return ReprEntry(lines, reprargs, localsrepr, filelocrepr, style)
         if excinfo:
             lines.extend(self.get_exconly(excinfo, indent=4))
@@ -598,24 +608,54 @@ class FormattedExcinfo(object):
         traceback = excinfo.traceback
         if self.tbfilter:
             traceback = traceback.filter()
-        recursionindex = None
+
         if is_recursion_error(excinfo):
-            recursionindex = traceback.recursionindex()
+            traceback, extraline = self._truncate_recursive_traceback(traceback)
+        else:
+            extraline = None
+
         last = traceback[-1]
         entries = []
-        extraline = None
         for index, entry in enumerate(traceback):
             einfo = (last == entry) and excinfo or None
             reprentry = self.repr_traceback_entry(entry, einfo)
             entries.append(reprentry)
-            if index == recursionindex:
-                extraline = "!!! Recursion detected (same locals & position)"
-                break
         return ReprTraceback(entries, extraline, style=self.style)
 
+    def _truncate_recursive_traceback(self, traceback):
+        """
+        Truncate the given recursive traceback trying to find the starting point
+        of the recursion.
+
+        The detection is done by going through each traceback entry and finding the
+        point in which the locals of the frame are equal to the locals of a previous frame (see ``recursionindex()``.
+
+        Handle the situation where the recursion process might raise an exception (for example
+        comparing numpy arrays using equality raises a TypeError), in which case we do our best to
+        warn the user of the error and show a limited traceback.
+        """
+        try:
+            recursionindex = traceback.recursionindex()
+        except Exception as e:
+            max_frames = 10
+            extraline = (
+                '!!! Recursion error detected, but an error occurred locating the origin of recursion.\n'
+                '  The following exception happened when comparing locals in the stack frame:\n'
+                '    {exc_type}: {exc_msg}\n'
+                '  Displaying first and last {max_frames} stack frames out of {total}.'
+            ).format(exc_type=type(e).__name__, exc_msg=safe_str(e), max_frames=max_frames, total=len(traceback))
+            traceback = traceback[:max_frames] + traceback[-max_frames:]
+        else:
+            if recursionindex is not None:
+                extraline = "!!! Recursion detected (same locals & position)"
+                traceback = traceback[:recursionindex + 1]
+            else:
+                extraline = None
+
+        return traceback, extraline
 
     def repr_excinfo(self, excinfo):
-        if sys.version_info[0] < 3:
+        if _PY2:
             reprtraceback = self.repr_traceback(excinfo)
             reprcrash = excinfo._getreprcrash()
 
@@ -639,7 +679,7 @@ class FormattedExcinfo(object):
                     e = e.__cause__
                     excinfo = ExceptionInfo((type(e), e, e.__traceback__)) if e.__traceback__ else None
                     descr = 'The above exception was the direct cause of the following exception:'
-                elif e.__context__ is not None:
+                elif (e.__context__ is not None and not e.__suppress_context__):
                     e = e.__context__
                     excinfo = ExceptionInfo((type(e), e, e.__traceback__)) if e.__traceback__ else None
                     descr = 'During handling of the above exception, another exception occurred:'
@@ -652,7 +692,7 @@ class FormattedExcinfo(object):
 class TerminalRepr(object):
     def __str__(self):
         s = self.__unicode__()
-        if sys.version_info[0] < 3:
+        if _PY2:
             s = s.encode('utf-8')
         return s
 
@@ -665,7 +705,7 @@ class TerminalRepr(object):
         return io.getvalue().strip()
 
     def __repr__(self):
-        return "<%s instance at %0x>" %(self.__class__, id(self))
+        return "<%s instance at %0x>" % (self.__class__, id(self))
 
 
 class ExceptionRepr(TerminalRepr):
@@ -709,6 +749,7 @@ class ReprExceptionInfo(ExceptionRepr):
         self.reprtraceback.toterminal(tw)
         super(ReprExceptionInfo, self).toterminal(tw)
 
+
 class ReprTraceback(TerminalRepr):
     entrysep = "_ "
 
@@ -724,7 +765,7 @@ class ReprTraceback(TerminalRepr):
                 tw.line("")
             entry.toterminal(tw)
             if i < len(self.reprentries) - 1:
-                next_entry = self.reprentries[i+1]
+                next_entry = self.reprentries[i + 1]
                 if entry.style == "long" or \
                    entry.style == "short" and next_entry.style == "long":
                     tw.sep(self.entrysep)
@@ -732,12 +773,14 @@ class ReprTraceback(TerminalRepr):
         if self.extraline:
             tw.line(self.extraline)
 
+
 class ReprTracebackNative(ReprTraceback):
     def __init__(self, tblines):
         self.style = "native"
         self.reprentries = [ReprEntryNative(tblines)]
         self.extraline = None
 
+
 class ReprEntryNative(TerminalRepr):
     style = "native"
 
@@ -747,6 +790,7 @@ class ReprEntryNative(TerminalRepr):
     def toterminal(self, tw):
         tw.write("".join(self.lines))
 
+
 class ReprEntry(TerminalRepr):
     localssep = "_ "
 
@@ -763,7 +807,7 @@ class ReprEntry(TerminalRepr):
             for line in self.lines:
                 red = line.startswith("E   ")
                 tw.line(line, bold=True, red=red)
-            #tw.line("")
+            # tw.line("")
             return
         if self.reprfuncargs:
             self.reprfuncargs.toterminal(tw)
@@ -771,7 +815,7 @@ class ReprEntry(TerminalRepr):
             red = line.startswith("E   ")
             tw.line(line, bold=True, red=red)
         if self.reprlocals:
-            #tw.sep(self.localssep, "Locals")
+            # tw.sep(self.localssep, "Locals")
             tw.line("")
             self.reprlocals.toterminal(tw)
         if self.reprfileloc:
@@ -784,6 +828,7 @@ class ReprEntry(TerminalRepr):
                                self.reprlocals,
                                self.reprfileloc)
 
+
 class ReprFileLocation(TerminalRepr):
     def __init__(self, path, lineno, message):
         self.path = str(path)
@@ -800,6 +845,7 @@ class ReprFileLocation(TerminalRepr):
         tw.write(self.path, bold=True, red=True)
         tw.line(":%s: %s" % (self.lineno, msg))
 
+
 class ReprLocals(TerminalRepr):
     def __init__(self, lines):
         self.lines = lines
@@ -808,6 +854,7 @@ class ReprLocals(TerminalRepr):
         for line in self.lines:
             tw.line(line)
 
+
 class ReprFuncArgs(TerminalRepr):
     def __init__(self, args):
         self.args = args
@@ -816,11 +863,11 @@ class ReprFuncArgs(TerminalRepr):
         if self.args:
             linesofar = ""
             for name, value in self.args:
-                ns = "%s = %s" %(name, value)
+                ns = "%s = %s" % (safe_str(name), safe_str(value))
                 if len(ns) + len(linesofar) + 2 > tw.fullwidth:
                     if linesofar:
                         tw.line(linesofar)
-                    linesofar =  ns
+                    linesofar = ns
                 else:
                     if linesofar:
                         linesofar += ", " + ns
@@ -848,7 +895,7 @@ def getrawcode(obj, trycall=True):
         return obj
 
 
-if sys.version_info[:2] >= (3, 5):  # RecursionError introduced in 3.5
+if PY35:  # RecursionError introduced in 3.5
     def is_recursion_error(excinfo):
         return excinfo.errisinstance(RecursionError)  # noqa
 else:
diff --git a/lib/spack/external/_pytest/_code/source.py b/lib/spack/external/_pytest/_code/source.py
index fcec0f5ca7..fc41712649 100644
--- a/lib/spack/external/_pytest/_code/source.py
+++ b/lib/spack/external/_pytest/_code/source.py
@@ -1,8 +1,9 @@
-from __future__ import generators
+from __future__ import absolute_import, division, generators, print_function
 
 from bisect import bisect_right
 import sys
-import inspect, tokenize
+import inspect
+import tokenize
 import py
 cpy_compile = compile
 
@@ -19,6 +20,7 @@ class Source(object):
         possibly deindenting it.
     """
     _compilecounter = 0
+
     def __init__(self, *parts, **kwargs):
         self.lines = lines = []
         de = kwargs.get('deindent', True)
@@ -73,7 +75,7 @@ class Source(object):
         start, end = 0, len(self)
         while start < end and not self.lines[start].strip():
             start += 1
-        while end > start and not self.lines[end-1].strip():
+        while end > start and not self.lines[end - 1].strip():
             end -= 1
         source = Source()
         source.lines[:] = self.lines[start:end]
@@ -86,8 +88,8 @@ class Source(object):
         before = Source(before)
         after = Source(after)
         newsource = Source()
-        lines = [ (indent + line) for line in self.lines]
-        newsource.lines = before.lines + lines +  after.lines
+        lines = [(indent + line) for line in self.lines]
+        newsource.lines = before.lines + lines + after.lines
         return newsource
 
     def indent(self, indent=' ' * 4):
@@ -95,7 +97,7 @@ class Source(object):
             all lines indented by the given indent-string.
         """
         newsource = Source()
-        newsource.lines = [(indent+line) for line in self.lines]
+        newsource.lines = [(indent + line) for line in self.lines]
         return newsource
 
     def getstatement(self, lineno, assertion=False):
@@ -134,7 +136,8 @@ class Source(object):
         try:
             import parser
         except ImportError:
-            syntax_checker = lambda x: compile(x, 'asd', 'exec')
+            def syntax_checker(x):
+                return compile(x, 'asd', 'exec')
         else:
             syntax_checker = parser.suite
 
@@ -143,8 +146,8 @@ class Source(object):
         else:
             source = str(self)
         try:
-            #compile(source+'\n', "x", "exec")
-            syntax_checker(source+'\n')
+            # compile(source+'\n', "x", "exec")
+            syntax_checker(source + '\n')
         except KeyboardInterrupt:
             raise
         except Exception:
@@ -164,8 +167,8 @@ class Source(object):
         """
         if not filename or py.path.local(filename).check(file=0):
             if _genframe is None:
-                _genframe = sys._getframe(1) # the caller
-            fn,lineno = _genframe.f_code.co_filename, _genframe.f_lineno
+                _genframe = sys._getframe(1)  # the caller
+            fn, lineno = _genframe.f_code.co_filename, _genframe.f_lineno
             base = "<%d-codegen " % self._compilecounter
             self.__class__._compilecounter += 1
             if not filename:
@@ -180,7 +183,7 @@ class Source(object):
             # re-represent syntax errors from parsing python strings
             msglines = self.lines[:ex.lineno]
             if ex.offset:
-                msglines.append(" "*ex.offset + '^')
+                msglines.append(" " * ex.offset + '^')
             msglines.append("(code was compiled probably from here: %s)" % filename)
             newex = SyntaxError('\n'.join(msglines))
             newex.offset = ex.offset
@@ -198,8 +201,8 @@ class Source(object):
 # public API shortcut functions
 #
 
-def compile_(source, filename=None, mode='exec', flags=
-            generators.compiler_flag, dont_inherit=0):
+
+def compile_(source, filename=None, mode='exec', flags=generators.compiler_flag, dont_inherit=0):
     """ compile the given source to a raw code object,
         and maintain an internal cache which allows later
         retrieval of the source code for the code object
@@ -208,7 +211,7 @@ def compile_(source, filename=None, mode='exec', flags=
     if _ast is not None and isinstance(source, _ast.AST):
         # XXX should Source support having AST?
         return cpy_compile(source, filename, mode, flags, dont_inherit)
-    _genframe = sys._getframe(1) # the caller
+    _genframe = sys._getframe(1)  # the caller
     s = Source(source)
     co = s.compile(filename, mode, flags, _genframe=_genframe)
     return co
@@ -245,12 +248,13 @@ def getfslineno(obj):
 # helper functions
 #
 
+
 def findsource(obj):
     try:
         sourcelines, lineno = py.std.inspect.findsource(obj)
     except py.builtin._sysex:
         raise
-    except:
+    except:  # noqa
         return None, -1
     source = Source()
     source.lines = [line.rstrip() for line in sourcelines]
@@ -274,7 +278,7 @@ def deindent(lines, offset=None):
             line = line.expandtabs()
             s = line.lstrip()
             if s:
-                offset = len(line)-len(s)
+                offset = len(line) - len(s)
                 break
         else:
             offset = 0
@@ -293,11 +297,11 @@ def deindent(lines, offset=None):
     try:
         for _, _, (sline, _), (eline, _), _ in tokenize.generate_tokens(lambda: next(it)):
             if sline > len(lines):
-                break # End of input reached
+                break  # End of input reached
             if sline > len(newlines):
                 line = lines[sline - 1].expandtabs()
                 if line.lstrip() and line[:offset].isspace():
-                    line = line[offset:] # Deindent
+                    line = line[offset:]  # Deindent
                 newlines.append(line)
 
             for i in range(sline, eline):
@@ -315,29 +319,29 @@ def get_statement_startend2(lineno, node):
     import ast
     # flatten all statements and except handlers into one lineno-list
     # AST's line numbers start indexing at 1
-    l = []
+    values = []
     for x in ast.walk(node):
         if isinstance(x, _ast.stmt) or isinstance(x, _ast.ExceptHandler):
-            l.append(x.lineno - 1)
+            values.append(x.lineno - 1)
             for name in "finalbody", "orelse":
                 val = getattr(x, name, None)
                 if val:
                     # treat the finally/orelse part as its own statement
-                    l.append(val[0].lineno - 1 - 1)
-    l.sort()
-    insert_index = bisect_right(l, lineno)
-    start = l[insert_index - 1]
-    if insert_index >= len(l):
+                    values.append(val[0].lineno - 1 - 1)
+    values.sort()
+    insert_index = bisect_right(values, lineno)
+    start = values[insert_index - 1]
+    if insert_index >= len(values):
         end = None
     else:
-        end = l[insert_index]
+        end = values[insert_index]
     return start, end
 
 
 def getstatementrange_ast(lineno, source, assertion=False, astnode=None):
     if astnode is None:
         content = str(source)
-        if sys.version_info < (2,7):
+        if sys.version_info < (2, 7):
             content += "\n"
         try:
             astnode = compile(content, "source", "exec", 1024)  # 1024 for AST
@@ -393,7 +397,7 @@ def getstatementrange_old(lineno, source, assertion=False):
                 raise IndexError("likely a subclass")
             if "assert" not in line and "raise" not in line:
                 continue
-        trylines = source.lines[start:lineno+1]
+        trylines = source.lines[start:lineno + 1]
         # quick hack to prepare parsing an indented line with
         # compile_command() (which errors on "return" outside defs)
         trylines.insert(0, 'def xxx():')
@@ -405,10 +409,8 @@ def getstatementrange_old(lineno, source, assertion=False):
             continue
 
         # 2. find the end of the statement
-        for end in range(lineno+1, len(source)+1):
+        for end in range(lineno + 1, len(source) + 1):
             trysource = source[start:end]
             if trysource.isparseable():
                 return start, end
     raise SyntaxError("no valid source range around line %d " % (lineno,))
-
-
diff --git a/lib/spack/external/_pytest/_pluggy.py b/lib/spack/external/_pytest/_pluggy.py
index 87d32cf8dd..6cc1d3d54a 100644
--- a/lib/spack/external/_pytest/_pluggy.py
+++ b/lib/spack/external/_pytest/_pluggy.py
@@ -2,7 +2,7 @@
 imports symbols from vendored "pluggy" if available, otherwise
 falls back to importing "pluggy" from the default namespace.
 """
-
+from __future__ import absolute_import, division, print_function
 try:
     from _pytest.vendored_packages.pluggy import *  # noqa
     from _pytest.vendored_packages.pluggy import __version__  # noqa
diff --git a/lib/spack/external/_pytest/assertion/__init__.py b/lib/spack/external/_pytest/assertion/__init__.py
index 3f14a7ae76..b0ef667d56 100644
--- a/lib/spack/external/_pytest/assertion/__init__.py
+++ b/lib/spack/external/_pytest/assertion/__init__.py
@@ -1,12 +1,13 @@
 """
 support for presenting detailed information in failing assertions.
 """
+from __future__ import absolute_import, division, print_function
 import py
-import os
 import sys
 
 from _pytest.assertion import util
 from _pytest.assertion import rewrite
+from _pytest.assertion import truncate
 
 
 def pytest_addoption(parser):
@@ -24,10 +25,6 @@ def pytest_addoption(parser):
                             expression information.""")
 
 
-def pytest_namespace():
-    return {'register_assert_rewrite': register_assert_rewrite}
-
-
 def register_assert_rewrite(*names):
     """Register one or more module names to be rewritten on import.
 
@@ -100,12 +97,6 @@ def pytest_collection(session):
             assertstate.hook.set_session(session)
 
 
-def _running_on_ci():
-    """Check if we're currently running on a CI system."""
-    env_vars = ['CI', 'BUILD_NUMBER']
-    return any(var in os.environ for var in env_vars)
-
-
 def pytest_runtest_setup(item):
     """Setup the pytest_assertrepr_compare hook
 
@@ -119,8 +110,8 @@ def pytest_runtest_setup(item):
 
         This uses the first result from the hook and then ensures the
         following:
-        * Overly verbose explanations are dropped unless -vv was used or
-          running on a CI.
+        * Overly verbose explanations are truncated unless configured otherwise
+          (eg. if running in verbose mode).
         * Embedded newlines are escaped to help util.format_explanation()
           later.
         * If the rewrite mode is used embedded %-characters are replaced
@@ -133,14 +124,7 @@ def pytest_runtest_setup(item):
             config=item.config, op=op, left=left, right=right)
         for new_expl in hook_result:
             if new_expl:
-                if (sum(len(p) for p in new_expl[1:]) > 80*8 and
-                        item.config.option.verbose < 2 and
-                        not _running_on_ci()):
-                    show_max = 10
-                    truncated_lines = len(new_expl) - show_max
-                    new_expl[show_max:] = [py.builtin._totext(
-                        'Detailed information truncated (%d more lines)'
-                        ', use "-vv" to show' % truncated_lines)]
+                new_expl = truncate.truncate_if_required(new_expl, item)
                 new_expl = [line.replace("\n", "\\n") for line in new_expl]
                 res = py.builtin._totext("\n~").join(new_expl)
                 if item.config.getvalue("assertmode") == "rewrite":
diff --git a/lib/spack/external/_pytest/assertion/rewrite.py b/lib/spack/external/_pytest/assertion/rewrite.py
index abf5b491fe..d48b6648fb 100644
--- a/lib/spack/external/_pytest/assertion/rewrite.py
+++ b/lib/spack/external/_pytest/assertion/rewrite.py
@@ -1,5 +1,5 @@
 """Rewrite assertion AST to produce nice error messages"""
-
+from __future__ import absolute_import, division, print_function
 import ast
 import _ast
 import errno
@@ -11,7 +11,6 @@ import re
 import struct
 import sys
 import types
-from fnmatch import fnmatch
 
 import py
 from _pytest.assertion import util
@@ -37,10 +36,11 @@ PYC_TAIL = "." + PYTEST_TAG + PYC_EXT
 REWRITE_NEWLINES = sys.version_info[:2] != (2, 7) and sys.version_info < (3, 2)
 ASCII_IS_DEFAULT_ENCODING = sys.version_info[0] < 3
 
-if sys.version_info >= (3,5):
+if sys.version_info >= (3, 5):
     ast_Call = ast.Call
 else:
-    ast_Call = lambda a,b,c: ast.Call(a, b, c, None, None)
+    def ast_Call(a, b, c):
+        return ast.Call(a, b, c, None, None)
 
 
 class AssertionRewritingHook(object):
@@ -163,11 +163,7 @@ class AssertionRewritingHook(object):
         # modules not passed explicitly on the command line are only
         # rewritten if they match the naming convention for test files
         for pat in self.fnpats:
-            # use fnmatch instead of fn_pypath.fnmatch because the
-            # latter might trigger an import to fnmatch.fnmatch
-            # internally, which would cause this method to be
-            # called recursively
-            if fnmatch(fn_pypath.basename, pat):
+            if fn_pypath.fnmatch(pat):
                 state.trace("matched test file %r" % (fn,))
                 return True
 
@@ -214,13 +210,12 @@ class AssertionRewritingHook(object):
             mod.__cached__ = pyc
             mod.__loader__ = self
             py.builtin.exec_(co, mod.__dict__)
-        except:
-            del sys.modules[name]
+        except:  # noqa
+            if name in sys.modules:
+                del sys.modules[name]
             raise
         return sys.modules[name]
 
-
-
     def is_package(self, name):
         try:
             fd, fn, desc = imp.find_module(name)
@@ -265,7 +260,7 @@ def _write_pyc(state, co, source_stat, pyc):
         fp = open(pyc, "wb")
     except IOError:
         err = sys.exc_info()[1].errno
-        state.trace("error writing pyc file at %s: errno=%s" %(pyc, err))
+        state.trace("error writing pyc file at %s: errno=%s" % (pyc, err))
         # we ignore any failure to write the cache file
         # there are many reasons, permission-denied, __pycache__ being a
         # file etc.
@@ -287,6 +282,7 @@ N = "\n".encode("utf-8")
 cookie_re = re.compile(r"^[ \t\f]*#.*coding[:=][ \t]*[-\w.]+")
 BOM_UTF8 = '\xef\xbb\xbf'
 
+
 def _rewrite_test(config, fn):
     """Try to read and rewrite *fn* and return the code object."""
     state = config._assertstate
@@ -311,7 +307,7 @@ def _rewrite_test(config, fn):
         end2 = source.find("\n", end1 + 1)
         if (not source.startswith(BOM_UTF8) and
             cookie_re.match(source[0:end1]) is None and
-            cookie_re.match(source[end1 + 1:end2]) is None):
+                cookie_re.match(source[end1 + 1:end2]) is None):
             if hasattr(state, "_indecode"):
                 # encodings imported us again, so don't rewrite.
                 return None, None
@@ -336,7 +332,7 @@ def _rewrite_test(config, fn):
         return None, None
     rewrite_asserts(tree, fn, config)
     try:
-        co = compile(tree, fn.strpath, "exec")
+        co = compile(tree, fn.strpath, "exec", dont_inherit=True)
     except SyntaxError:
         # It's possible that this error is from some bug in the
         # assertion rewriting, but I don't know of a fast way to tell.
@@ -344,6 +340,7 @@ def _rewrite_test(config, fn):
         return None, None
     return stat, co
 
+
 def _make_rewritten_pyc(state, source_stat, pyc, co):
     """Try to dump rewritten code to *pyc*."""
     if sys.platform.startswith("win"):
@@ -357,6 +354,7 @@ def _make_rewritten_pyc(state, source_stat, pyc, co):
         if _write_pyc(state, co, source_stat, proc_pyc):
             os.rename(proc_pyc, pyc)
 
+
 def _read_pyc(source, pyc, trace=lambda x: None):
     """Possibly read a pytest pyc containing rewritten code.
 
@@ -414,7 +412,8 @@ def _saferepr(obj):
     return repr.replace(t("\n"), t("\\n"))
 
 
-from _pytest.assertion.util import format_explanation as _format_explanation # noqa
+from _pytest.assertion.util import format_explanation as _format_explanation  # noqa
+
 
 def _format_assertmsg(obj):
     """Format the custom assertion message given.
@@ -443,9 +442,11 @@ def _format_assertmsg(obj):
         s = s.replace(t("\\n"), t("\n~"))
     return s
 
+
 def _should_repr_global_name(obj):
     return not hasattr(obj, "__name__") and not py.builtin.callable(obj)
 
+
 def _format_boolop(explanations, is_or):
     explanation = "(" + (is_or and " or " or " and ").join(explanations) + ")"
     if py.builtin._istext(explanation):
@@ -454,6 +455,7 @@ def _format_boolop(explanations, is_or):
         t = py.builtin.bytes
     return explanation.replace(t('%'), t('%%'))
 
+
 def _call_reprcompare(ops, results, expls, each_obj):
     for i, res, expl in zip(range(len(ops)), results, expls):
         try:
@@ -487,7 +489,7 @@ binop_map = {
     ast.Mult: "*",
     ast.Div: "/",
     ast.FloorDiv: "//",
-    ast.Mod: "%%", # escaped for string formatting
+    ast.Mod: "%%",  # escaped for string formatting
     ast.Eq: "==",
     ast.NotEq: "!=",
     ast.Lt: "<",
@@ -593,23 +595,26 @@ class AssertionRewriter(ast.NodeVisitor):
         # docstrings and __future__ imports.
         aliases = [ast.alias(py.builtin.builtins.__name__, "@py_builtins"),
                    ast.alias("_pytest.assertion.rewrite", "@pytest_ar")]
-        expect_docstring = True
+        doc = getattr(mod, "docstring", None)
+        expect_docstring = doc is None
+        if doc is not None and self.is_rewrite_disabled(doc):
+            return
         pos = 0
-        lineno = 0
+        lineno = 1
         for item in mod.body:
             if (expect_docstring and isinstance(item, ast.Expr) and
                     isinstance(item.value, ast.Str)):
                 doc = item.value.s
-                if "PYTEST_DONT_REWRITE" in doc:
-                    # The module has disabled assertion rewriting.
+                if self.is_rewrite_disabled(doc):
                     return
-                lineno += len(doc) - 1
                 expect_docstring = False
             elif (not isinstance(item, ast.ImportFrom) or item.level > 0 or
                   item.module != "__future__"):
                 lineno = item.lineno
                 break
             pos += 1
+        else:
+            lineno = item.lineno
         imports = [ast.Import([alias], lineno=lineno, col_offset=0)
                    for alias in aliases]
         mod.body[pos:pos] = imports
@@ -635,6 +640,9 @@ class AssertionRewriter(ast.NodeVisitor):
                       not isinstance(field, ast.expr)):
                     nodes.append(field)
 
+    def is_rewrite_disabled(self, docstring):
+        return "PYTEST_DONT_REWRITE" in docstring
+
     def variable(self):
         """Get a new variable."""
         # Use a character invalid in python identifiers to avoid clashing.
@@ -727,7 +735,7 @@ class AssertionRewriter(ast.NodeVisitor):
         if isinstance(assert_.test, ast.Tuple) and self.config is not None:
             fslocation = (self.module_path, assert_.lineno)
             self.config.warn('R1', 'assertion is always true, perhaps '
-                              'remove parentheses?', fslocation=fslocation)
+                             'remove parentheses?', fslocation=fslocation)
         self.statements = []
         self.variables = []
         self.variable_counter = itertools.count()
@@ -791,7 +799,7 @@ class AssertionRewriter(ast.NodeVisitor):
             if i:
                 fail_inner = []
                 # cond is set in a prior loop iteration below
-                self.on_failure.append(ast.If(cond, fail_inner, [])) # noqa
+                self.on_failure.append(ast.If(cond, fail_inner, []))  # noqa
                 self.on_failure = fail_inner
             self.push_format_context()
             res, expl = self.visit(v)
@@ -843,7 +851,7 @@ class AssertionRewriter(ast.NodeVisitor):
             new_kwargs.append(ast.keyword(keyword.arg, res))
             if keyword.arg:
                 arg_expls.append(keyword.arg + "=" + expl)
-            else: ## **args have `arg` keywords with an .arg of None
+            else:  # **args have `arg` keywords with an .arg of None
                 arg_expls.append("**" + expl)
 
         expl = "%s(%s)" % (func_expl, ', '.join(arg_expls))
@@ -897,7 +905,6 @@ class AssertionRewriter(ast.NodeVisitor):
     else:
         visit_Call = visit_Call_legacy
 
-
     def visit_Attribute(self, attr):
         if not isinstance(attr.ctx, ast.Load):
             return self.generic_visit(attr)
diff --git a/lib/spack/external/_pytest/assertion/truncate.py b/lib/spack/external/_pytest/assertion/truncate.py
new file mode 100644
index 0000000000..1e13063569
--- /dev/null
+++ b/lib/spack/external/_pytest/assertion/truncate.py
@@ -0,0 +1,102 @@
+"""
+Utilities for truncating assertion output.
+
+Current default behaviour is to truncate assertion explanations at
+~8 terminal lines, unless running in "-vv" mode or running on CI.
+"""
+from __future__ import absolute_import, division, print_function
+import os
+
+import py
+
+
+DEFAULT_MAX_LINES = 8
+DEFAULT_MAX_CHARS = 8 * 80
+USAGE_MSG = "use '-vv' to show"
+
+
+def truncate_if_required(explanation, item, max_length=None):
+    """
+    Truncate this assertion explanation if the given test item is eligible.
+    """
+    if _should_truncate_item(item):
+        return _truncate_explanation(explanation)
+    return explanation
+
+
+def _should_truncate_item(item):
+    """
+    Whether or not this test item is eligible for truncation.
+    """
+    verbose = item.config.option.verbose
+    return verbose < 2 and not _running_on_ci()
+
+
+def _running_on_ci():
+    """Check if we're currently running on a CI system."""
+    env_vars = ['CI', 'BUILD_NUMBER']
+    return any(var in os.environ for var in env_vars)
+
+
+def _truncate_explanation(input_lines, max_lines=None, max_chars=None):
+    """
+    Truncate given list of strings that makes up the assertion explanation.
+
+    Truncates to either 8 lines, or 640 characters - whichever the input reaches
+    first. The remaining lines will be replaced by a usage message.
+    """
+
+    if max_lines is None:
+        max_lines = DEFAULT_MAX_LINES
+    if max_chars is None:
+        max_chars = DEFAULT_MAX_CHARS
+
+    # Check if truncation required
+    input_char_count = len("".join(input_lines))
+    if len(input_lines) <= max_lines and input_char_count <= max_chars:
+        return input_lines
+
+    # Truncate first to max_lines, and then truncate to max_chars if max_chars
+    # is exceeded.
+    truncated_explanation = input_lines[:max_lines]
+    truncated_explanation = _truncate_by_char_count(truncated_explanation, max_chars)
+
+    # Add ellipsis to final line
+    truncated_explanation[-1] = truncated_explanation[-1] + "..."
+
+    # Append useful message to explanation
+    truncated_line_count = len(input_lines) - len(truncated_explanation)
+    truncated_line_count += 1  # Account for the part-truncated final line
+    msg = '...Full output truncated'
+    if truncated_line_count == 1:
+        msg += ' ({0} line hidden)'.format(truncated_line_count)
+    else:
+        msg += ' ({0} lines hidden)'.format(truncated_line_count)
+    msg += ", {0}" .format(USAGE_MSG)
+    truncated_explanation.extend([
+        py.builtin._totext(""),
+        py.builtin._totext(msg),
+    ])
+    return truncated_explanation
+
+
+def _truncate_by_char_count(input_lines, max_chars):
+    # Check if truncation required
+    if len("".join(input_lines)) <= max_chars:
+        return input_lines
+
+    # Find point at which input length exceeds total allowed length
+    iterated_char_count = 0
+    for iterated_index, input_line in enumerate(input_lines):
+        if iterated_char_count + len(input_line) > max_chars:
+            break
+        iterated_char_count += len(input_line)
+
+    # Create truncated explanation with modified final line
+    truncated_result = input_lines[:iterated_index]
+    final_line = input_lines[iterated_index]
+    if final_line:
+        final_line_truncate_point = max_chars - iterated_char_count
+        final_line = final_line[:final_line_truncate_point]
+    truncated_result.append(final_line)
+    return truncated_result
diff --git a/lib/spack/external/_pytest/assertion/util.py b/lib/spack/external/_pytest/assertion/util.py
index 4a0a4e4310..9f00929073 100644
--- a/lib/spack/external/_pytest/assertion/util.py
+++ b/lib/spack/external/_pytest/assertion/util.py
@@ -1,4 +1,5 @@
 """Utilities for assertion debugging"""
+from __future__ import absolute_import, division, print_function
 import pprint
 
 import _pytest._code
@@ -8,7 +9,7 @@ try:
 except ImportError:
     Sequence = list
 
-BuiltinAssertionError = py.builtin.builtins.AssertionError
+
 u = py.builtin._totext
 
 # The _reprcompare attribute on the util module is used by the new assertion
@@ -52,11 +53,11 @@ def _split_explanation(explanation):
     """
     raw_lines = (explanation or u('')).split('\n')
     lines = [raw_lines[0]]
-    for l in raw_lines[1:]:
-        if l and l[0] in ['{', '}', '~', '>']:
-            lines.append(l)
+    for values in raw_lines[1:]:
+        if values and values[0] in ['{', '}', '~', '>']:
+            lines.append(values)
         else:
-            lines[-1] += '\\n' + l
+            lines[-1] += '\\n' + values
     return lines
 
 
@@ -81,7 +82,7 @@ def _format_lines(lines):
             stack.append(len(result))
             stackcnt[-1] += 1
             stackcnt.append(0)
-            result.append(u(' +') + u('  ')*(len(stack)-1) + s + line[1:])
+            result.append(u(' +') + u('  ') * (len(stack) - 1) + s + line[1:])
         elif line.startswith('}'):
             stack.pop()
             stackcnt.pop()
@@ -90,7 +91,7 @@ def _format_lines(lines):
             assert line[0] in ['~', '>']
             stack[-1] += 1
             indent = len(stack) if line.startswith('~') else len(stack) - 1
-            result.append(u('  ')*indent + line[1:])
+            result.append(u('  ') * indent + line[1:])
     assert len(stack) == 1
     return result
 
@@ -105,16 +106,22 @@ except NameError:
 def assertrepr_compare(config, op, left, right):
     """Return specialised explanations for some operators/operands"""
     width = 80 - 15 - len(op) - 2  # 15 chars indentation, 1 space around op
-    left_repr = py.io.saferepr(left, maxsize=int(width//2))
-    right_repr = py.io.saferepr(right, maxsize=width-len(left_repr))
+    left_repr = py.io.saferepr(left, maxsize=int(width // 2))
+    right_repr = py.io.saferepr(right, maxsize=width - len(left_repr))
 
     summary = u('%s %s %s') % (ecu(left_repr), op, ecu(right_repr))
 
-    issequence = lambda x: (isinstance(x, (list, tuple, Sequence)) and
-                            not isinstance(x, basestring))
-    istext = lambda x: isinstance(x, basestring)
-    isdict = lambda x: isinstance(x, dict)
-    isset = lambda x: isinstance(x, (set, frozenset))
+    def issequence(x):
+        return (isinstance(x, (list, tuple, Sequence)) and not isinstance(x, basestring))
+
+    def istext(x):
+        return isinstance(x, basestring)
+
+    def isdict(x):
+        return isinstance(x, dict)
+
+    def isset(x):
+        return isinstance(x, (set, frozenset))
 
     def isiterable(obj):
         try:
@@ -256,8 +263,8 @@ def _compare_eq_dict(left, right, verbose=False):
     explanation = []
     common = set(left).intersection(set(right))
     same = dict((k, left[k]) for k in common if left[k] == right[k])
-    if same and not verbose:
-        explanation += [u('Omitting %s identical items, use -v to show') %
+    if same and verbose < 2:
+        explanation += [u('Omitting %s identical items, use -vv to show') %
                         len(same)]
     elif same:
         explanation += [u('Common items:')]
@@ -284,7 +291,7 @@ def _compare_eq_dict(left, right, verbose=False):
 def _notin_text(term, text, verbose=False):
     index = text.find(term)
     head = text[:index]
-    tail = text[index+len(term):]
+    tail = text[index + len(term):]
     correct_text = head + tail
     diff = _diff_text(correct_text, text, verbose)
     newdiff = [u('%s is contained here:') % py.io.saferepr(term, maxsize=42)]
diff --git a/lib/spack/external/_pytest/cacheprovider.py b/lib/spack/external/_pytest/cacheprovider.py
index 0657001f2d..c537c14472 100644..100755
--- a/lib/spack/external/_pytest/cacheprovider.py
+++ b/lib/spack/external/_pytest/cacheprovider.py
@@ -1,20 +1,21 @@
 """
 merged implementation of the cache provider
 
-the name cache was not choosen to ensure pluggy automatically
+the name cache was not chosen to ensure pluggy automatically
 ignores the external pytest-cache
 """
-
+from __future__ import absolute_import, division, print_function
 import py
 import pytest
 import json
+import os
 from os.path import sep as _sep, altsep as _altsep
 
 
 class Cache(object):
     def __init__(self, config):
         self.config = config
-        self._cachedir = config.rootdir.join(".cache")
+        self._cachedir = Cache.cache_dir_from_config(config)
         self.trace = config.trace.root.get("cache")
         if config.getvalue("cacheclear"):
             self.trace("clearing cachedir")
@@ -22,6 +23,16 @@ class Cache(object):
                 self._cachedir.remove()
             self._cachedir.mkdir()
 
+    @staticmethod
+    def cache_dir_from_config(config):
+        cache_dir = config.getini("cache_dir")
+        cache_dir = os.path.expanduser(cache_dir)
+        cache_dir = os.path.expandvars(cache_dir)
+        if os.path.isabs(cache_dir):
+            return py.path.local(cache_dir)
+        else:
+            return config.rootdir.join(cache_dir)
+
     def makedir(self, name):
         """ return a directory path object with the given name.  If the
         directory does not yet exist, it will be created.  You can use it
@@ -89,31 +100,31 @@ class Cache(object):
 
 class LFPlugin:
     """ Plugin which implements the --lf (run last-failing) option """
+
     def __init__(self, config):
         self.config = config
         active_keys = 'lf', 'failedfirst'
         self.active = any(config.getvalue(key) for key in active_keys)
-        if self.active:
-            self.lastfailed = config.cache.get("cache/lastfailed", {})
-        else:
-            self.lastfailed = {}
+        self.lastfailed = config.cache.get("cache/lastfailed", {})
+        self._previously_failed_count = None
 
-    def pytest_report_header(self):
+    def pytest_report_collectionfinish(self):
         if self.active:
-            if not self.lastfailed:
+            if not self._previously_failed_count:
                 mode = "run all (no recorded failures)"
             else:
-                mode = "rerun last %d failures%s" % (
-                    len(self.lastfailed),
-                    " first" if self.config.getvalue("failedfirst") else "")
+                noun = 'failure' if self._previously_failed_count == 1 else 'failures'
+                suffix = " first" if self.config.getvalue("failedfirst") else ""
+                mode = "rerun previous {count} {noun}{suffix}".format(
+                    count=self._previously_failed_count, suffix=suffix, noun=noun
+                )
             return "run-last-failure: %s" % mode
 
     def pytest_runtest_logreport(self, report):
-        if report.failed and "xfail" not in report.keywords:
+        if (report.when == 'call' and report.passed) or report.skipped:
+            self.lastfailed.pop(report.nodeid, None)
+        elif report.failed:
             self.lastfailed[report.nodeid] = True
-        elif not report.failed:
-            if report.when == "call":
-                self.lastfailed.pop(report.nodeid, None)
 
     def pytest_collectreport(self, report):
         passed = report.outcome in ('passed', 'skipped')
@@ -135,22 +146,24 @@ class LFPlugin:
                     previously_failed.append(item)
                 else:
                     previously_passed.append(item)
-            if not previously_failed and previously_passed:
+            self._previously_failed_count = len(previously_failed)
+            if not previously_failed:
                 # running a subset of all tests with recorded failures outside
                 # of the set of tests currently executing
-                pass
-            elif self.config.getvalue("failedfirst"):
-                items[:] = previously_failed + previously_passed
-            else:
+                return
+            if self.config.getvalue("lf"):
                 items[:] = previously_failed
                 config.hook.pytest_deselected(items=previously_passed)
+            else:
+                items[:] = previously_failed + previously_passed
 
     def pytest_sessionfinish(self, session):
         config = self.config
         if config.getvalue("cacheshow") or hasattr(config, "slaveinput"):
             return
-        prev_failed = config.cache.get("cache/lastfailed", None) is not None
-        if (session.testscollected and prev_failed) or self.lastfailed:
+
+        saved_lastfailed = config.cache.get("cache/lastfailed", {})
+        if saved_lastfailed != self.lastfailed:
             config.cache.set("cache/lastfailed", self.lastfailed)
 
 
@@ -171,6 +184,9 @@ def pytest_addoption(parser):
     group.addoption(
         '--cache-clear', action='store_true', dest="cacheclear",
         help="remove all cache contents at start of test run.")
+    parser.addini(
+        "cache_dir", default='.cache',
+        help="cache directory path.")
 
 
 def pytest_cmdline_main(config):
@@ -179,7 +195,6 @@ def pytest_cmdline_main(config):
         return wrap_session(config, cacheshow)
 
 
-
 @pytest.hookimpl(tryfirst=True)
 def pytest_configure(config):
     config.cache = Cache(config)
@@ -219,12 +234,12 @@ def cacheshow(config, session):
     basedir = config.cache._cachedir
     vdir = basedir.join("v")
     tw.sep("-", "cache values")
-    for valpath in vdir.visit(lambda x: x.isfile()):
+    for valpath in sorted(vdir.visit(lambda x: x.isfile())):
         key = valpath.relto(vdir).replace(valpath.sep, "/")
         val = config.cache.get(key, dummy)
         if val is dummy:
             tw.line("%s contains unreadable content, "
-                  "will be ignored" % key)
+                    "will be ignored" % key)
         else:
             tw.line("%s contains:" % key)
             stream = py.io.TextIO()
@@ -235,8 +250,8 @@ def cacheshow(config, session):
     ddir = basedir.join("d")
     if ddir.isdir() and ddir.listdir():
         tw.sep("-", "cache directories")
-        for p in basedir.join("d").visit():
-            #if p.check(dir=1):
+        for p in sorted(basedir.join("d").visit()):
+            # if p.check(dir=1):
             #    print("%s/" % p.relto(basedir))
             if p.isfile():
                 key = p.relto(basedir)
diff --git a/lib/spack/external/_pytest/capture.py b/lib/spack/external/_pytest/capture.py
index eea81ca187..cb5af6fcb3 100644
--- a/lib/spack/external/_pytest/capture.py
+++ b/lib/spack/external/_pytest/capture.py
@@ -2,17 +2,19 @@
 per-test stdout/stderr capturing mechanism.
 
 """
-from __future__ import with_statement
+from __future__ import absolute_import, division, print_function
 
 import contextlib
 import sys
 import os
+import io
+from io import UnsupportedOperation
 from tempfile import TemporaryFile
 
 import py
 import pytest
+from _pytest.compat import CaptureIO
 
-from py.io import TextIO
 unicode = py.builtin.text
 
 patchsysdict = {0: 'stdin', 1: 'stdout', 2: 'stderr'}
@@ -32,8 +34,11 @@ def pytest_addoption(parser):
 
 @pytest.hookimpl(hookwrapper=True)
 def pytest_load_initial_conftests(early_config, parser, args):
-    _readline_workaround()
     ns = early_config.known_args_namespace
+    if ns.capture == "fd":
+        _py36_windowsconsoleio_workaround(sys.stdout)
+    _colorama_workaround()
+    _readline_workaround()
     pluginmanager = early_config.pluginmanager
     capman = CaptureManager(ns.capture)
     pluginmanager.register(capman, "capturemanager")
@@ -130,7 +135,7 @@ class CaptureManager:
         self.resumecapture()
         self.activate_funcargs(item)
         yield
-        #self.deactivate_funcargs() called from suspendcapture()
+        # self.deactivate_funcargs() called from suspendcapture()
         self.suspendcapture_item(item, "call")
 
     @pytest.hookimpl(hookwrapper=True)
@@ -167,6 +172,7 @@ def capsys(request):
     request.node._capfuncarg = c = CaptureFixture(SysCapture, request)
     return c
 
+
 @pytest.fixture
 def capfd(request):
     """Enable capturing of writes to file descriptors 1 and 2 and make
@@ -234,6 +240,7 @@ def safe_text_dupfile(f, mode, default_encoding="UTF8"):
 
 class EncodedFile(object):
     errors = "strict"  # possibly needed by py3 code (issue555)
+
     def __init__(self, buffer, encoding):
         self.buffer = buffer
         self.encoding = encoding
@@ -247,6 +254,11 @@ class EncodedFile(object):
         data = ''.join(linelist)
         self.write(data)
 
+    @property
+    def name(self):
+        """Ensure that file.name is a string."""
+        return repr(self.buffer)
+
     def __getattr__(self, name):
         return getattr(object.__getattribute__(self, "buffer"), name)
 
@@ -314,9 +326,11 @@ class MultiCapture(object):
         return (self.out.snap() if self.out is not None else "",
                 self.err.snap() if self.err is not None else "")
 
+
 class NoCapture:
     __init__ = start = done = suspend = resume = lambda *args: None
 
+
 class FDCapture:
     """ Capture IO to/from a given os-level filedescriptor. """
 
@@ -389,7 +403,7 @@ class FDCapture:
     def writeorg(self, data):
         """ write to original file descriptor. """
         if py.builtin._istext(data):
-            data = data.encode("utf8") # XXX use encoding of original stream
+            data = data.encode("utf8")  # XXX use encoding of original stream
         os.write(self.targetfd_save, data)
 
 
@@ -402,7 +416,7 @@ class SysCapture:
             if name == "stdin":
                 tmpfile = DontReadFromInput()
             else:
-                tmpfile = TextIO()
+                tmpfile = CaptureIO()
         self.tmpfile = tmpfile
 
     def start(self):
@@ -448,7 +462,8 @@ class DontReadFromInput:
     __iter__ = read
 
     def fileno(self):
-        raise ValueError("redirected Stdin is pseudofile, has no fileno()")
+        raise UnsupportedOperation("redirected stdin is pseudofile, "
+                                   "has no fileno()")
 
     def isatty(self):
         return False
@@ -458,12 +473,30 @@ class DontReadFromInput:
 
     @property
     def buffer(self):
-        if sys.version_info >= (3,0):
+        if sys.version_info >= (3, 0):
             return self
         else:
             raise AttributeError('redirected stdin has no attribute buffer')
 
 
+def _colorama_workaround():
+    """
+    Ensure colorama is imported so that it attaches to the correct stdio
+    handles on Windows.
+
+    colorama uses the terminal on import time. So if something does the
+    first import of colorama while I/O capture is active, colorama will
+    fail in various ways.
+    """
+
+    if not sys.platform.startswith('win32'):
+        return
+    try:
+        import colorama  # noqa
+    except ImportError:
+        pass
+
+
 def _readline_workaround():
     """
     Ensure readline is imported so that it attaches to the correct stdio
@@ -489,3 +522,56 @@ def _readline_workaround():
         import readline  # noqa
     except ImportError:
         pass
+
+
+def _py36_windowsconsoleio_workaround(stream):
+    """
+    Python 3.6 implemented unicode console handling for Windows. This works
+    by reading/writing to the raw console handle using
+    ``{Read,Write}ConsoleW``.
+
+    The problem is that we are going to ``dup2`` over the stdio file
+    descriptors when doing ``FDCapture`` and this will ``CloseHandle`` the
+    handles used by Python to write to the console. Though there is still some
+    weirdness and the console handle seems to only be closed randomly and not
+    on the first call to ``CloseHandle``, or maybe it gets reopened with the
+    same handle value when we suspend capturing.
+
+    The workaround in this case will reopen stdio with a different fd which
+    also means a different handle by replicating the logic in
+    "Py_lifecycle.c:initstdio/create_stdio".
+
+    :param stream: in practice ``sys.stdout`` or ``sys.stderr``, but given
+        here as parameter for unittesting purposes.
+
+    See https://github.com/pytest-dev/py/issues/103
+    """
+    if not sys.platform.startswith('win32') or sys.version_info[:2] < (3, 6):
+        return
+
+    # bail out if ``stream`` doesn't seem like a proper ``io`` stream (#2666)
+    if not hasattr(stream, 'buffer'):
+        return
+
+    buffered = hasattr(stream.buffer, 'raw')
+    raw_stdout = stream.buffer.raw if buffered else stream.buffer
+
+    if not isinstance(raw_stdout, io._WindowsConsoleIO):
+        return
+
+    def _reopen_stdio(f, mode):
+        if not buffered and mode[0] == 'w':
+            buffering = 0
+        else:
+            buffering = -1
+
+        return io.TextIOWrapper(
+            open(os.dup(f.fileno()), mode, buffering),
+            f.encoding,
+            f.errors,
+            f.newlines,
+            f.line_buffering)
+
+    sys.__stdin__ = sys.stdin = _reopen_stdio(sys.stdin, 'rb')
+    sys.__stdout__ = sys.stdout = _reopen_stdio(sys.stdout, 'wb')
+    sys.__stderr__ = sys.stderr = _reopen_stdio(sys.stderr, 'wb')
diff --git a/lib/spack/external/_pytest/compat.py b/lib/spack/external/_pytest/compat.py
index 51fc3bc5c1..255f69ce0d 100644
--- a/lib/spack/external/_pytest/compat.py
+++ b/lib/spack/external/_pytest/compat.py
@@ -1,6 +1,7 @@
 """
 python version compatibility code
 """
+from __future__ import absolute_import, division, print_function
 import sys
 import inspect
 import types
@@ -9,8 +10,8 @@ import functools
 
 import py
 
-import  _pytest
-
+import _pytest
+from _pytest.outcomes import TEST_OUTCOME
 
 
 try:
@@ -19,6 +20,7 @@ except ImportError:  # pragma: no cover
     # Only available in Python 3.4+ or as a backport
     enum = None
 
+
 _PY3 = sys.version_info > (3, 0)
 _PY2 = not _PY3
 
@@ -26,6 +28,10 @@ _PY2 = not _PY3
 NoneType = type(None)
 NOTSET = object()
 
+PY35 = sys.version_info[:2] >= (3, 5)
+PY36 = sys.version_info[:2] >= (3, 6)
+MODULE_NOT_FOUND_ERROR = 'ModuleNotFoundError' if PY36 else 'ImportError'
+
 if hasattr(inspect, 'signature'):
     def _format_args(func):
         return str(inspect.signature(func))
@@ -42,11 +48,18 @@ REGEX_TYPE = type(re.compile(''))
 
 
 def is_generator(func):
-    try:
-        return _pytest._code.getrawcode(func).co_flags & 32 # generator function
-    except AttributeError: # builtin functions have no bytecode
-        # assume them to not be generators
-        return False
+    genfunc = inspect.isgeneratorfunction(func)
+    return genfunc and not iscoroutinefunction(func)
+
+
+def iscoroutinefunction(func):
+    """Return True if func is a decorated coroutine function.
+
+    Note: copied and modified from Python 3.5's builtin couroutines.py to avoid import asyncio directly,
+    which in turns also initializes the "logging" module as side-effect (see issue #8).
+    """
+    return (getattr(func, '_is_coroutine', False) or
+            (hasattr(inspect, 'iscoroutinefunction') and inspect.iscoroutinefunction(func)))
 
 
 def getlocation(function, curdir):
@@ -55,7 +68,7 @@ def getlocation(function, curdir):
     lineno = py.builtin._getcode(function).co_firstlineno
     if fn.relto(curdir):
         fn = fn.relto(curdir)
-    return "%s:%d" %(fn, lineno+1)
+    return "%s:%d" % (fn, lineno + 1)
 
 
 def num_mock_patch_args(function):
@@ -66,13 +79,21 @@ def num_mock_patch_args(function):
     mock = sys.modules.get("mock", sys.modules.get("unittest.mock", None))
     if mock is not None:
         return len([p for p in patchings
-                        if not p.attribute_name and p.new is mock.DEFAULT])
+                    if not p.attribute_name and p.new is mock.DEFAULT])
     return len(patchings)
 
 
-def getfuncargnames(function, startindex=None):
+def getfuncargnames(function, startindex=None, cls=None):
+    """
+    @RonnyPfannschmidt: This function should be refactored when we revisit fixtures. The
+    fixture mechanism should ask the node for the fixture names, and not try to obtain
+    directly from the function object well after collection has occurred.
+    """
+    if startindex is None and cls is not None:
+        is_staticmethod = isinstance(cls.__dict__.get(function.__name__, None), staticmethod)
+        startindex = 0 if is_staticmethod else 1
     # XXX merge with main.py's varnames
-    #assert not isclass(function)
+    # assert not isclass(function)
     realfunction = function
     while hasattr(realfunction, "__wrapped__"):
         realfunction = realfunction.__wrapped__
@@ -98,8 +119,7 @@ def getfuncargnames(function, startindex=None):
     return tuple(argnames[startindex:])
 
 
-
-if  sys.version_info[:2] == (2, 6):
+if sys.version_info[:2] == (2, 6):
     def isclass(object):
         """ Return true if the object is a class. Overrides inspect.isclass for
         python 2.6 because it will return True for objects which always return
@@ -111,10 +131,12 @@ if  sys.version_info[:2] == (2, 6):
 
 if _PY3:
     import codecs
-
+    imap = map
+    izip = zip
     STRING_TYPES = bytes, str
+    UNICODE_TYPES = str,
 
-    def _escape_strings(val):
+    def _ascii_escaped(val):
         """If val is pure ascii, returns it as a str().  Otherwise, escapes
         bytes objects into a sequence of escaped bytes:
 
@@ -144,8 +166,11 @@ if _PY3:
             return val.encode('unicode_escape').decode('ascii')
 else:
     STRING_TYPES = bytes, str, unicode
+    UNICODE_TYPES = unicode,
 
-    def _escape_strings(val):
+    from itertools import imap, izip  # NOQA
+
+    def _ascii_escaped(val):
         """In py2 bytes and str are the same type, so return if it's a bytes
         object, return it unchanged if it is a full ascii string,
         otherwise escape it into its binary form.
@@ -167,8 +192,18 @@ def get_real_func(obj):
     """ gets the real function object of the (possibly) wrapped object by
     functools.wraps or functools.partial.
     """
-    while hasattr(obj, "__wrapped__"):
-        obj = obj.__wrapped__
+    start_obj = obj
+    for i in range(100):
+        new_obj = getattr(obj, '__wrapped__', None)
+        if new_obj is None:
+            break
+        obj = new_obj
+    else:
+        raise ValueError(
+            ("could not find real function of {start}"
+             "\nstopped at {current}").format(
+                start=py.io.saferepr(start_obj),
+                current=py.io.saferepr(obj)))
     if isinstance(obj, functools.partial):
         obj = obj.func
     return obj
@@ -195,14 +230,16 @@ def getimfunc(func):
 
 
 def safe_getattr(object, name, default):
-    """ Like getattr but return default upon any Exception.
+    """ Like getattr but return default upon any Exception or any OutcomeException.
 
     Attribute access can potentially fail for 'evil' Python objects.
-    See issue214
+    See issue #214.
+    It catches OutcomeException because of #2490 (issue #580), new outcomes are derived from BaseException
+    instead of Exception (for more details check #2707)
     """
     try:
         return getattr(object, name, default)
-    except Exception:
+    except TEST_OUTCOME:
         return default
 
 
@@ -226,5 +263,64 @@ else:
         try:
             return str(v)
         except UnicodeError:
+            if not isinstance(v, unicode):
+                v = unicode(v)
             errors = 'replace'
-            return v.encode('ascii', errors)
+            return v.encode('utf-8', errors)
+
+
+COLLECT_FAKEMODULE_ATTRIBUTES = (
+    'Collector',
+    'Module',
+    'Generator',
+    'Function',
+    'Instance',
+    'Session',
+    'Item',
+    'Class',
+    'File',
+    '_fillfuncargs',
+)
+
+
+def _setup_collect_fakemodule():
+    from types import ModuleType
+    import pytest
+    pytest.collect = ModuleType('pytest.collect')
+    pytest.collect.__all__ = []  # used for setns
+    for attr in COLLECT_FAKEMODULE_ATTRIBUTES:
+        setattr(pytest.collect, attr, getattr(pytest, attr))
+
+
+if _PY2:
+    # Without this the test_dupfile_on_textio will fail, otherwise CaptureIO could directly inherit from StringIO.
+    from py.io import TextIO
+
+    class CaptureIO(TextIO):
+
+        @property
+        def encoding(self):
+            return getattr(self, '_encoding', 'UTF-8')
+
+else:
+    import io
+
+    class CaptureIO(io.TextIOWrapper):
+        def __init__(self):
+            super(CaptureIO, self).__init__(
+                io.BytesIO(),
+                encoding='UTF-8', newline='', write_through=True,
+            )
+
+        def getvalue(self):
+            return self.buffer.getvalue().decode('UTF-8')
+
+
+class FuncargnamesCompatAttr(object):
+    """ helper class so that Metafunc, Function and FixtureRequest
+    don't need to each define the "funcargnames" compatibility attribute.
+    """
+    @property
+    def funcargnames(self):
+        """ alias attribute for ``fixturenames`` for pre-2.3 compatibility"""
+        return self.fixturenames
diff --git a/lib/spack/external/_pytest/config.py b/lib/spack/external/_pytest/config.py
index fe386ed0b1..19835d2c39 100644
--- a/lib/spack/external/_pytest/config.py
+++ b/lib/spack/external/_pytest/config.py
@@ -1,4 +1,5 @@
 """ command line options, ini-file and conftest.py processing. """
+from __future__ import absolute_import, division, print_function
 import argparse
 import shlex
 import traceback
@@ -7,7 +8,8 @@ import warnings
 
 import py
 # DON't import pytest here because it causes import cycle troubles
-import sys, os
+import sys
+import os
 import _pytest._code
 import _pytest.hookspec  # the extension point definitions
 import _pytest.assertion
@@ -53,15 +55,15 @@ def main(args=None, plugins=None):
             return 4
         else:
             try:
-                config.pluginmanager.check_pending()
                 return config.hook.pytest_cmdline_main(config=config)
             finally:
                 config._ensure_unconfigure()
     except UsageError as e:
         for msg in e.args:
-            sys.stderr.write("ERROR: %s\n" %(msg,))
+            sys.stderr.write("ERROR: %s\n" % (msg,))
         return 4
 
+
 class cmdline:  # compatibility namespace
     main = staticmethod(main)
 
@@ -70,6 +72,12 @@ class UsageError(Exception):
     """ error in pytest usage or invocation"""
 
 
+class PrintHelp(Exception):
+    """Raised when pytest should print it's help to skip the rest of the
+    argument parsing and validation."""
+    pass
+
+
 def filename_arg(path, optname):
     """ Argparse type validator for filename arguments.
 
@@ -95,10 +103,11 @@ def directory_arg(path, optname):
 _preinit = []
 
 default_plugins = (
-     "mark main terminal runner python fixtures debugging unittest capture skipping "
-     "tmpdir monkeypatch recwarn pastebin helpconfig nose assertion "
-     "junitxml resultlog doctest cacheprovider freeze_support "
-     "setuponly setupplan").split()
+    "mark main terminal runner python fixtures debugging unittest capture skipping "
+    "tmpdir monkeypatch recwarn pastebin helpconfig nose assertion "
+    "junitxml resultlog doctest cacheprovider freeze_support "
+    "setuponly setupplan warnings").split()
+
 
 builtin_plugins = set(default_plugins)
 builtin_plugins.add("pytester")
@@ -108,6 +117,7 @@ def _preloadplugins():
     assert not _preinit
     _preinit.append(get_config())
 
+
 def get_config():
     if _preinit:
         return _preinit.pop(0)
@@ -118,6 +128,7 @@ def get_config():
         pluginmanager.import_plugin(spec)
     return config
 
+
 def get_plugin_manager():
     """
     Obtain a new instance of the
@@ -129,6 +140,7 @@ def get_plugin_manager():
     """
     return get_config().pluginmanager
 
+
 def _prepareconfig(args=None, plugins=None):
     warning = None
     if args is None:
@@ -153,7 +165,7 @@ def _prepareconfig(args=None, plugins=None):
         if warning:
             config.warn('C1', warning)
         return pluginmanager.hook.pytest_cmdline_parse(
-                pluginmanager=pluginmanager, args=args)
+            pluginmanager=pluginmanager, args=args)
     except BaseException:
         config._ensure_unconfigure()
         raise
@@ -161,13 +173,14 @@ def _prepareconfig(args=None, plugins=None):
 
 class PytestPluginManager(PluginManager):
     """
-    Overwrites :py:class:`pluggy.PluginManager` to add pytest-specific
+    Overwrites :py:class:`pluggy.PluginManager <_pytest.vendored_packages.pluggy.PluginManager>` to add pytest-specific
     functionality:
 
     * loading plugins from the command line, ``PYTEST_PLUGIN`` env variable and
       ``pytest_plugins`` global variables found in plugins being loaded;
     * ``conftest.py`` loading during start-up;
     """
+
     def __init__(self):
         super(PytestPluginManager, self).__init__("pytest", implprefix="pytest_")
         self._conftest_plugins = set()
@@ -198,7 +211,8 @@ class PytestPluginManager(PluginManager):
         """
         .. deprecated:: 2.8
 
-        Use :py:meth:`pluggy.PluginManager.add_hookspecs` instead.
+        Use :py:meth:`pluggy.PluginManager.add_hookspecs <_pytest.vendored_packages.pluggy.PluginManager.add_hookspecs>`
+        instead.
         """
         warning = dict(code="I2",
                        fslocation=_pytest._code.getfslineno(sys._getframe(1)),
@@ -227,7 +241,7 @@ class PytestPluginManager(PluginManager):
 
     def parse_hookspec_opts(self, module_or_class, name):
         opts = super(PytestPluginManager, self).parse_hookspec_opts(
-                                                module_or_class, name)
+            module_or_class, name)
         if opts is None:
             method = getattr(module_or_class, name)
             if name.startswith("pytest_"):
@@ -250,7 +264,10 @@ class PytestPluginManager(PluginManager):
         ret = super(PytestPluginManager, self).register(plugin, name)
         if ret:
             self.hook.pytest_plugin_registered.call_historic(
-                      kwargs=dict(plugin=plugin, manager=self))
+                kwargs=dict(plugin=plugin, manager=self))
+
+            if isinstance(plugin, types.ModuleType):
+                self.consider_module(plugin)
         return ret
 
     def getplugin(self, name):
@@ -265,11 +282,11 @@ class PytestPluginManager(PluginManager):
         # XXX now that the pluginmanager exposes hookimpl(tryfirst...)
         # we should remove tryfirst/trylast as markers
         config.addinivalue_line("markers",
-            "tryfirst: mark a hook implementation function such that the "
-            "plugin machinery will try to call it first/as early as possible.")
+                                "tryfirst: mark a hook implementation function such that the "
+                                "plugin machinery will try to call it first/as early as possible.")
         config.addinivalue_line("markers",
-            "trylast: mark a hook implementation function such that the "
-            "plugin machinery will try to call it last/as late as possible.")
+                                "trylast: mark a hook implementation function such that the "
+                                "plugin machinery will try to call it last/as late as possible.")
 
     def _warn(self, message):
         kwargs = message if isinstance(message, dict) else {
@@ -293,7 +310,7 @@ class PytestPluginManager(PluginManager):
         """
         current = py.path.local()
         self._confcutdir = current.join(namespace.confcutdir, abs=True) \
-                                if namespace.confcutdir else None
+            if namespace.confcutdir else None
         self._noconftest = namespace.noconftest
         testpaths = namespace.file_or_dir
         foundanchor = False
@@ -304,7 +321,7 @@ class PytestPluginManager(PluginManager):
             if i != -1:
                 path = path[:i]
             anchor = current.join(path, abs=1)
-            if exists(anchor): # we found some file object
+            if exists(anchor):  # we found some file object
                 self._try_load_conftest(anchor)
                 foundanchor = True
         if not foundanchor:
@@ -371,7 +388,7 @@ class PytestPluginManager(PluginManager):
                     if path and path.relto(dirpath) or path == dirpath:
                         assert mod not in mods
                         mods.append(mod)
-            self.trace("loaded conftestmodule %r" %(mod))
+            self.trace("loaded conftestmodule %r" % (mod))
             self.consider_conftest(mod)
             return mod
 
@@ -381,7 +398,7 @@ class PytestPluginManager(PluginManager):
     #
 
     def consider_preparse(self, args):
-        for opt1,opt2 in zip(args, args[1:]):
+        for opt1, opt2 in zip(args, args[1:]):
             if opt1 == "-p":
                 self.consider_pluginarg(opt2)
 
@@ -395,38 +412,33 @@ class PytestPluginManager(PluginManager):
             self.import_plugin(arg)
 
     def consider_conftest(self, conftestmodule):
-        if self.register(conftestmodule, name=conftestmodule.__file__):
-            self.consider_module(conftestmodule)
+        self.register(conftestmodule, name=conftestmodule.__file__)
 
     def consider_env(self):
         self._import_plugin_specs(os.environ.get("PYTEST_PLUGINS"))
 
     def consider_module(self, mod):
-        plugins = getattr(mod, 'pytest_plugins', [])
-        if isinstance(plugins, str):
-            plugins = [plugins]
-        self.rewrite_hook.mark_rewrite(*plugins)
-        self._import_plugin_specs(plugins)
+        self._import_plugin_specs(getattr(mod, 'pytest_plugins', []))
 
     def _import_plugin_specs(self, spec):
-        if spec:
-            if isinstance(spec, str):
-                spec = spec.split(",")
-            for import_spec in spec:
-                self.import_plugin(import_spec)
+        plugins = _get_plugin_specs_as_list(spec)
+        for import_spec in plugins:
+            self.import_plugin(import_spec)
 
     def import_plugin(self, modname):
         # most often modname refers to builtin modules, e.g. "pytester",
         # "terminal" or "capture".  Those plugins are registered under their
         # basename for historic purposes but must be imported with the
         # _pytest prefix.
-        assert isinstance(modname, str)
+        assert isinstance(modname, (py.builtin.text, str)), "module name as text required, got %r" % modname
+        modname = str(modname)
         if self.get_plugin(modname) is not None:
             return
         if modname in builtin_plugins:
             importspec = "_pytest." + modname
         else:
             importspec = modname
+        self.rewrite_hook.mark_rewrite(importspec)
         try:
             __import__(importspec)
         except ImportError as e:
@@ -440,11 +452,28 @@ class PytestPluginManager(PluginManager):
             import pytest
             if not hasattr(pytest, 'skip') or not isinstance(e, pytest.skip.Exception):
                 raise
-            self._warn("skipped plugin %r: %s" %((modname, e.msg)))
+            self._warn("skipped plugin %r: %s" % ((modname, e.msg)))
         else:
             mod = sys.modules[importspec]
             self.register(mod, modname)
-            self.consider_module(mod)
+
+
+def _get_plugin_specs_as_list(specs):
+    """
+    Parses a list of "plugin specs" and returns a list of plugin names.
+
+    Plugin specs can be given as a list of strings separated by "," or already as a list/tuple in
+    which case it is returned as a list. Specs can also be `None` in which case an
+    empty list is returned.
+    """
+    if specs is not None:
+        if isinstance(specs, str):
+            specs = specs.split(',') if specs else []
+        if not isinstance(specs, (list, tuple)):
+            raise UsageError("Plugin specs must be a ','-separated string or a "
+                             "list/tuple of strings for plugin names. Given: %r" % specs)
+        return list(specs)
+    return []
 
 
 class Parser:
@@ -488,7 +517,7 @@ class Parser:
         for i, grp in enumerate(self._groups):
             if grp.name == after:
                 break
-        self._groups.insert(i+1, group)
+        self._groups.insert(i + 1, group)
         return group
 
     def addoption(self, *opts, **attrs):
@@ -526,7 +555,7 @@ class Parser:
                     a = option.attrs()
                     arggroup.add_argument(*n, **a)
         # bash like autocompletion for dirs (appending '/')
-        optparser.add_argument(FILE_OR_DIR, nargs='*').completer=filescompleter
+        optparser.add_argument(FILE_OR_DIR, nargs='*').completer = filescompleter
         return optparser
 
     def parse_setoption(self, args, option, namespace=None):
@@ -670,7 +699,7 @@ class Argument:
         if self._attrs.get('help'):
             a = self._attrs['help']
             a = a.replace('%default', '%(default)s')
-            #a = a.replace('%prog', '%(prog)s')
+            # a = a.replace('%prog', '%(prog)s')
             self._attrs['help'] = a
         return self._attrs
 
@@ -754,7 +783,7 @@ class MyOptionParser(argparse.ArgumentParser):
             extra_info = {}
         self._parser = parser
         argparse.ArgumentParser.__init__(self, usage=parser._usage,
-            add_help=False, formatter_class=DropShorterLongHelpFormatter)
+                                         add_help=False, formatter_class=DropShorterLongHelpFormatter)
         # extra_info is a dict of (param -> value) to display if there's
         # an usage error to provide more contextual information to the user
         self.extra_info = extra_info
@@ -782,9 +811,10 @@ class DropShorterLongHelpFormatter(argparse.HelpFormatter):
     - shortcut if there are only two options and one of them is a short one
     - cache result on action object as this is called at least 2 times
     """
+
     def _format_action_invocation(self, action):
         orgstr = argparse.HelpFormatter._format_action_invocation(self, action)
-        if orgstr and orgstr[0] != '-': # only optional arguments
+        if orgstr and orgstr[0] != '-':  # only optional arguments
             return orgstr
         res = getattr(action, '_formatted_action_invocation', None)
         if res:
@@ -795,7 +825,7 @@ class DropShorterLongHelpFormatter(argparse.HelpFormatter):
             action._formatted_action_invocation = orgstr
             return orgstr
         return_list = []
-        option_map =  getattr(action, 'map_long_option', {})
+        option_map = getattr(action, 'map_long_option', {})
         if option_map is None:
             option_map = {}
         short_long = {}
@@ -813,7 +843,7 @@ class DropShorterLongHelpFormatter(argparse.HelpFormatter):
                     short_long[shortened] = xxoption
         # now short_long has been filled out to the longest with dashes
         # **and** we keep the right option ordering from add_argument
-        for option in options: #
+        for option in options:
             if len(option) == 2 or option[2] == ' ':
                 return_list.append(option)
             if option[2:] == short_long.get(option.replace('-', '')):
@@ -822,22 +852,26 @@ class DropShorterLongHelpFormatter(argparse.HelpFormatter):
         return action._formatted_action_invocation
 
 
-
 def _ensure_removed_sysmodule(modname):
     try:
         del sys.modules[modname]
     except KeyError:
         pass
 
+
 class CmdOptions(object):
     """ holds cmdline options as attributes."""
+
     def __init__(self, values=()):
         self.__dict__.update(values)
+
     def __repr__(self):
-        return "<CmdOptions %r>" %(self.__dict__,)
+        return "<CmdOptions %r>" % (self.__dict__,)
+
     def copy(self):
         return CmdOptions(self.__dict__)
 
+
 class Notset:
     def __repr__(self):
         return "<NOTSET>"
@@ -847,6 +881,18 @@ notset = Notset()
 FILE_OR_DIR = 'file_or_dir'
 
 
+def _iter_rewritable_modules(package_files):
+    for fn in package_files:
+        is_simple_module = '/' not in fn and fn.endswith('.py')
+        is_package = fn.count('/') == 1 and fn.endswith('__init__.py')
+        if is_simple_module:
+            module_name, _ = os.path.splitext(fn)
+            yield module_name
+        elif is_package:
+            package_name = os.path.dirname(fn)
+            yield package_name
+
+
 class Config(object):
     """ access to configuration values, pluginmanager and plugin hooks.  """
 
@@ -864,6 +910,7 @@ class Config(object):
         self.trace = self.pluginmanager.trace.root.get("config")
         self.hook = self.pluginmanager.hook
         self._inicache = {}
+        self._override_ini = ()
         self._opt2dest = {}
         self._cleanup = []
         self._warn = self.pluginmanager._warn
@@ -896,11 +943,11 @@ class Config(object):
             fin = self._cleanup.pop()
             fin()
 
-    def warn(self, code, message, fslocation=None):
+    def warn(self, code, message, fslocation=None, nodeid=None):
         """ generate a warning for this test session. """
         self.hook.pytest_logwarning.call_historic(kwargs=dict(
             code=code, message=message,
-            fslocation=fslocation, nodeid=None))
+            fslocation=fslocation, nodeid=nodeid))
 
     def get_terminal_writer(self):
         return self.pluginmanager.get_plugin("terminalreporter")._tw
@@ -916,14 +963,14 @@ class Config(object):
         else:
             style = "native"
         excrepr = excinfo.getrepr(funcargs=True,
-            showlocals=getattr(option, 'showlocals', False),
-            style=style,
-        )
+                                  showlocals=getattr(option, 'showlocals', False),
+                                  style=style,
+                                  )
         res = self.hook.pytest_internalerror(excrepr=excrepr,
                                              excinfo=excinfo)
         if not py.builtin.any(res):
             for line in str(excrepr).split("\n"):
-                sys.stderr.write("INTERNALERROR> %s\n" %line)
+                sys.stderr.write("INTERNALERROR> %s\n" % line)
                 sys.stderr.flush()
 
     def cwd_relative_nodeid(self, nodeid):
@@ -964,8 +1011,9 @@ class Config(object):
         self.invocation_dir = py.path.local()
         self._parser.addini('addopts', 'extra command line options', 'args')
         self._parser.addini('minversion', 'minimally required pytest version')
+        self._override_ini = ns.override_ini or ()
 
-    def _consider_importhook(self, args, entrypoint_name):
+    def _consider_importhook(self, args):
         """Install the PEP 302 import hook if using assertion re-writing.
 
         Needs to parse the --assert=<mode> option from the commandline
@@ -980,26 +1028,34 @@ class Config(object):
             except SystemError:
                 mode = 'plain'
             else:
-                import pkg_resources
-                self.pluginmanager.rewrite_hook = hook
-                for entrypoint in pkg_resources.iter_entry_points('pytest11'):
-                    # 'RECORD' available for plugins installed normally (pip install)
-                    # 'SOURCES.txt' available for plugins installed in dev mode (pip install -e)
-                    # for installed plugins 'SOURCES.txt' returns an empty list, and vice-versa
-                    # so it shouldn't be an issue
-                    for metadata in ('RECORD', 'SOURCES.txt'):
-                        for entry in entrypoint.dist._get_metadata(metadata):
-                            fn = entry.split(',')[0]
-                            is_simple_module = os.sep not in fn and fn.endswith('.py')
-                            is_package = fn.count(os.sep) == 1 and fn.endswith('__init__.py')
-                            if is_simple_module:
-                                module_name, ext = os.path.splitext(fn)
-                                hook.mark_rewrite(module_name)
-                            elif is_package:
-                                package_name = os.path.dirname(fn)
-                                hook.mark_rewrite(package_name)
+                self._mark_plugins_for_rewrite(hook)
         self._warn_about_missing_assertion(mode)
 
+    def _mark_plugins_for_rewrite(self, hook):
+        """
+        Given an importhook, mark for rewrite any top-level
+        modules or packages in the distribution package for
+        all pytest plugins.
+        """
+        import pkg_resources
+        self.pluginmanager.rewrite_hook = hook
+
+        # 'RECORD' available for plugins installed normally (pip install)
+        # 'SOURCES.txt' available for plugins installed in dev mode (pip install -e)
+        # for installed plugins 'SOURCES.txt' returns an empty list, and vice-versa
+        # so it shouldn't be an issue
+        metadata_files = 'RECORD', 'SOURCES.txt'
+
+        package_files = (
+            entry.split(',')[0]
+            for entrypoint in pkg_resources.iter_entry_points('pytest11')
+            for metadata in metadata_files
+            for entry in entrypoint.dist._get_metadata(metadata)
+        )
+
+        for name in _iter_rewritable_modules(package_files):
+            hook.mark_rewrite(name)
+
     def _warn_about_missing_assertion(self, mode):
         try:
             assert False
@@ -1023,19 +1079,17 @@ class Config(object):
             args[:] = shlex.split(os.environ.get('PYTEST_ADDOPTS', '')) + args
             args[:] = self.getini("addopts") + args
         self._checkversion()
-        entrypoint_name = 'pytest11'
-        self._consider_importhook(args, entrypoint_name)
+        self._consider_importhook(args)
         self.pluginmanager.consider_preparse(args)
-        self.pluginmanager.load_setuptools_entrypoints(entrypoint_name)
+        self.pluginmanager.load_setuptools_entrypoints('pytest11')
         self.pluginmanager.consider_env()
         self.known_args_namespace = ns = self._parser.parse_known_args(args, namespace=self.option.copy())
-        confcutdir = self.known_args_namespace.confcutdir
         if self.known_args_namespace.confcutdir is None and self.inifile:
             confcutdir = py.path.local(self.inifile).dirname
             self.known_args_namespace.confcutdir = confcutdir
         try:
             self.hook.pytest_load_initial_conftests(early_config=self,
-                    args=args, parser=self._parser)
+                                                    args=args, parser=self._parser)
         except ConftestImportFailure:
             e = sys.exc_info()[1]
             if ns.help or ns.version:
@@ -1053,28 +1107,32 @@ class Config(object):
             myver = pytest.__version__.split(".")
             if myver < ver:
                 raise pytest.UsageError(
-                    "%s:%d: requires pytest-%s, actual pytest-%s'" %(
-                    self.inicfg.config.path, self.inicfg.lineof('minversion'),
-                    minver, pytest.__version__))
+                    "%s:%d: requires pytest-%s, actual pytest-%s'" % (
+                        self.inicfg.config.path, self.inicfg.lineof('minversion'),
+                        minver, pytest.__version__))
 
     def parse(self, args, addopts=True):
         # parse given cmdline arguments into this config object.
         assert not hasattr(self, 'args'), (
-                "can only parse cmdline args at most once per Config object")
+            "can only parse cmdline args at most once per Config object")
         self._origargs = args
         self.hook.pytest_addhooks.call_historic(
-                                  kwargs=dict(pluginmanager=self.pluginmanager))
+            kwargs=dict(pluginmanager=self.pluginmanager))
         self._preparse(args, addopts=addopts)
         # XXX deprecated hook:
         self.hook.pytest_cmdline_preparse(config=self, args=args)
-        args = self._parser.parse_setoption(args, self.option, namespace=self.option)
-        if not args:
-            cwd = os.getcwd()
-            if cwd == self.rootdir:
-                args = self.getini('testpaths')
+        self._parser.after_preparse = True
+        try:
+            args = self._parser.parse_setoption(args, self.option, namespace=self.option)
             if not args:
-                args = [cwd]
-        self.args = args
+                cwd = os.getcwd()
+                if cwd == self.rootdir:
+                    args = self.getini('testpaths')
+                if not args:
+                    args = [cwd]
+            self.args = args
+        except PrintHelp:
+            pass
 
     def addinivalue_line(self, name, line):
         """ add a line to an ini-file option. The option must have been
@@ -1082,12 +1140,12 @@ class Config(object):
         the first line in its value. """
         x = self.getini(name)
         assert isinstance(x, list)
-        x.append(line) # modifies the cached list inline
+        x.append(line)  # modifies the cached list inline
 
     def getini(self, name):
         """ return configuration value from an :ref:`ini file <inifiles>`. If the
         specified name hasn't been registered through a prior
-        :py:func:`parser.addini <pytest.config.Parser.addini>`
+        :py:func:`parser.addini <_pytest.config.Parser.addini>`
         call (usually from a plugin), a ValueError is raised. """
         try:
             return self._inicache[name]
@@ -1099,7 +1157,7 @@ class Config(object):
         try:
             description, type, default = self._parser._inidict[name]
         except KeyError:
-            raise ValueError("unknown configuration value: %r" %(name,))
+            raise ValueError("unknown configuration value: %r" % (name,))
         value = self._get_override_ini_value(name)
         if value is None:
             try:
@@ -1112,10 +1170,10 @@ class Config(object):
                 return []
         if type == "pathlist":
             dp = py.path.local(self.inicfg.config.path).dirpath()
-            l = []
+            values = []
             for relpath in shlex.split(value):
-                l.append(dp.join(relpath, abs=True))
-            return l
+                values.append(dp.join(relpath, abs=True))
+            return values
         elif type == "args":
             return shlex.split(value)
         elif type == "linelist":
@@ -1132,13 +1190,13 @@ class Config(object):
         except KeyError:
             return None
         modpath = py.path.local(mod.__file__).dirpath()
-        l = []
+        values = []
         for relroot in relroots:
             if not isinstance(relroot, py.path.local):
                 relroot = relroot.replace("/", py.path.local.sep)
                 relroot = modpath.join(relroot, abs=True)
-            l.append(relroot)
-        return l
+            values.append(relroot)
+        return values
 
     def _get_override_ini_value(self, name):
         value = None
@@ -1146,15 +1204,14 @@ class Config(object):
         # and -o foo1=bar1 -o foo2=bar2 options
         # always use the last item if multiple value set for same ini-name,
         # e.g. -o foo=bar1 -o foo=bar2 will set foo to bar2
-        if self.getoption("override_ini", None):
-            for ini_config_list in self.option.override_ini:
-                for ini_config in ini_config_list:
-                    try:
-                        (key, user_ini_value) = ini_config.split("=", 1)
-                    except ValueError:
-                        raise UsageError("-o/--override-ini expects option=value style.")
-                    if key == name:
-                        value = user_ini_value
+        for ini_config_list in self._override_ini:
+            for ini_config in ini_config_list:
+                try:
+                    (key, user_ini_value) = ini_config.split("=", 1)
+                except ValueError:
+                    raise UsageError("-o/--override-ini expects option=value style.")
+                if key == name:
+                    value = user_ini_value
         return value
 
     def getoption(self, name, default=notset, skip=False):
@@ -1177,7 +1234,7 @@ class Config(object):
                 return default
             if skip:
                 import pytest
-                pytest.skip("no %r option found" %(name,))
+                pytest.skip("no %r option found" % (name,))
             raise ValueError("no option named %r" % (name,))
 
     def getvalue(self, name, path=None):
@@ -1188,12 +1245,14 @@ class Config(object):
         """ (deprecated, use getoption(skip=True)) """
         return self.getoption(name, skip=True)
 
+
 def exists(path, ignore=EnvironmentError):
     try:
         return path.check()
     except ignore:
         return False
 
+
 def getcfg(args, warnfunc=None):
     """
     Search the list of arguments for a valid ini-file for pytest,
@@ -1228,25 +1287,20 @@ def getcfg(args, warnfunc=None):
     return None, None, None
 
 
-def get_common_ancestor(args):
-    # args are what we get after early command line parsing (usually
-    # strings, but can be py.path.local objects as well)
+def get_common_ancestor(paths):
     common_ancestor = None
-    for arg in args:
-        if str(arg)[0] == "-":
-            continue
-        p = py.path.local(arg)
-        if not p.exists():
+    for path in paths:
+        if not path.exists():
             continue
         if common_ancestor is None:
-            common_ancestor = p
+            common_ancestor = path
         else:
-            if p.relto(common_ancestor) or p == common_ancestor:
+            if path.relto(common_ancestor) or path == common_ancestor:
                 continue
-            elif common_ancestor.relto(p):
-                common_ancestor = p
+            elif common_ancestor.relto(path):
+                common_ancestor = path
             else:
-                shared = p.common(common_ancestor)
+                shared = path.common(common_ancestor)
                 if shared is not None:
                     common_ancestor = shared
     if common_ancestor is None:
@@ -1257,9 +1311,29 @@ def get_common_ancestor(args):
 
 
 def get_dirs_from_args(args):
-    return [d for d in (py.path.local(x) for x in args
-                        if not str(x).startswith("-"))
-            if d.exists()]
+    def is_option(x):
+        return str(x).startswith('-')
+
+    def get_file_part_from_node_id(x):
+        return str(x).split('::')[0]
+
+    def get_dir_from_path(path):
+        if path.isdir():
+            return path
+        return py.path.local(path.dirname)
+
+    # These look like paths but may not exist
+    possible_paths = (
+        py.path.local(get_file_part_from_node_id(arg))
+        for arg in args
+        if not is_option(arg)
+    )
+
+    return [
+        get_dir_from_path(path)
+        for path in possible_paths
+        if path.exists()
+    ]
 
 
 def determine_setup(inifile, args, warnfunc=None):
@@ -1282,7 +1356,7 @@ def determine_setup(inifile, args, warnfunc=None):
                 rootdir, inifile, inicfg = getcfg(dirs, warnfunc=warnfunc)
                 if rootdir is None:
                     rootdir = get_common_ancestor([py.path.local(), ancestor])
-                    is_fs_root = os.path.splitdrive(str(rootdir))[1] == os.sep
+                    is_fs_root = os.path.splitdrive(str(rootdir))[1] == '/'
                     if is_fs_root:
                         rootdir = ancestor
     return rootdir, inifile, inicfg or {}
@@ -1304,7 +1378,7 @@ def setns(obj, dic):
         else:
             setattr(obj, name, value)
             obj.__all__.append(name)
-            #if obj != pytest:
+            # if obj != pytest:
             #    pytest.__all__.append(name)
             setattr(pytest, name, value)
 
diff --git a/lib/spack/external/_pytest/debugging.py b/lib/spack/external/_pytest/debugging.py
index d96170bd8b..aa9c9a3863 100644
--- a/lib/spack/external/_pytest/debugging.py
+++ b/lib/spack/external/_pytest/debugging.py
@@ -1,10 +1,8 @@
 """ interactive debugging with PDB, the Python Debugger. """
-from __future__ import absolute_import
+from __future__ import absolute_import, division, print_function
 import pdb
 import sys
 
-import pytest
-
 
 def pytest_addoption(parser):
     group = parser.getgroup("general")
@@ -16,19 +14,17 @@ def pytest_addoption(parser):
         help="start a custom interactive Python debugger on errors. "
              "For example: --pdbcls=IPython.terminal.debugger:TerminalPdb")
 
-def pytest_namespace():
-    return {'set_trace': pytestPDB().set_trace}
 
 def pytest_configure(config):
-    if config.getvalue("usepdb") or config.getvalue("usepdb_cls"):
+    if config.getvalue("usepdb_cls"):
+        modname, classname = config.getvalue("usepdb_cls").split(":")
+        __import__(modname)
+        pdb_cls = getattr(sys.modules[modname], classname)
+    else:
+        pdb_cls = pdb.Pdb
+
+    if config.getvalue("usepdb"):
         config.pluginmanager.register(PdbInvoke(), 'pdbinvoke')
-        if config.getvalue("usepdb_cls"):
-            modname, classname = config.getvalue("usepdb_cls").split(":")
-            __import__(modname)
-            pdb_cls = getattr(sys.modules[modname], classname)
-        else:
-            pdb_cls = pdb.Pdb
-        pytestPDB._pdb_cls = pdb_cls
 
     old = (pdb.set_trace, pytestPDB._pluginmanager)
 
@@ -37,30 +33,33 @@ def pytest_configure(config):
         pytestPDB._config = None
         pytestPDB._pdb_cls = pdb.Pdb
 
-    pdb.set_trace = pytest.set_trace
+    pdb.set_trace = pytestPDB.set_trace
     pytestPDB._pluginmanager = config.pluginmanager
     pytestPDB._config = config
+    pytestPDB._pdb_cls = pdb_cls
     config._cleanup.append(fin)
 
+
 class pytestPDB:
     """ Pseudo PDB that defers to the real pdb. """
     _pluginmanager = None
     _config = None
     _pdb_cls = pdb.Pdb
 
-    def set_trace(self):
+    @classmethod
+    def set_trace(cls):
         """ invoke PDB set_trace debugging, dropping any IO capturing. """
         import _pytest.config
         frame = sys._getframe().f_back
-        if self._pluginmanager is not None:
-            capman = self._pluginmanager.getplugin("capturemanager")
+        if cls._pluginmanager is not None:
+            capman = cls._pluginmanager.getplugin("capturemanager")
             if capman:
                 capman.suspendcapture(in_=True)
-            tw = _pytest.config.create_terminal_writer(self._config)
+            tw = _pytest.config.create_terminal_writer(cls._config)
             tw.line()
             tw.sep(">", "PDB set_trace (IO-capturing turned off)")
-            self._pluginmanager.hook.pytest_enter_pdb(config=self._config)
-        self._pdb_cls().set_trace(frame)
+            cls._pluginmanager.hook.pytest_enter_pdb(config=cls._config)
+        cls._pdb_cls().set_trace(frame)
 
 
 class PdbInvoke:
@@ -74,7 +73,7 @@ class PdbInvoke:
 
     def pytest_internalerror(self, excrepr, excinfo):
         for line in str(excrepr).split("\n"):
-            sys.stderr.write("INTERNALERROR> %s\n" %line)
+            sys.stderr.write("INTERNALERROR> %s\n" % line)
             sys.stderr.flush()
         tb = _postmortem_traceback(excinfo)
         post_mortem(tb)
diff --git a/lib/spack/external/_pytest/deprecated.py b/lib/spack/external/_pytest/deprecated.py
index 6edc475f6e..38e9496778 100644
--- a/lib/spack/external/_pytest/deprecated.py
+++ b/lib/spack/external/_pytest/deprecated.py
@@ -5,10 +5,15 @@ that is planned to be removed in the next pytest release.
 Keeping it in a central location makes it easy to track what is deprecated and should
 be removed when the time comes.
 """
+from __future__ import absolute_import, division, print_function
+
+
+class RemovedInPytest4Warning(DeprecationWarning):
+    """warning class for features removed in pytest 4.0"""
 
 
 MAIN_STR_ARGS = 'passing a string to pytest.main() is deprecated, ' \
-                      'pass a list of arguments instead.'
+    'pass a list of arguments instead.'
 
 YIELD_TESTS = 'yield tests are deprecated, and scheduled to be removed in pytest 4.0'
 
@@ -21,4 +26,17 @@ SETUP_CFG_PYTEST = '[pytest] section in setup.cfg files is deprecated, use [tool
 
 GETFUNCARGVALUE = "use of getfuncargvalue is deprecated, use getfixturevalue"
 
-RESULT_LOG = '--result-log is deprecated and scheduled for removal in pytest 4.0'
+RESULT_LOG = (
+    '--result-log is deprecated and scheduled for removal in pytest 4.0.\n'
+    'See https://docs.pytest.org/en/latest/usage.html#creating-resultlog-format-files for more information.'
+)
+
+MARK_INFO_ATTRIBUTE = RemovedInPytest4Warning(
+    "MarkInfo objects are deprecated as they contain the merged marks"
+)
+
+MARK_PARAMETERSET_UNPACKING = RemovedInPytest4Warning(
+    "Applying marks directly to parameters is deprecated,"
+    " please use pytest.param(..., marks=...) instead.\n"
+    "For more details, see: https://docs.pytest.org/en/latest/parametrize.html"
+)
diff --git a/lib/spack/external/_pytest/doctest.py b/lib/spack/external/_pytest/doctest.py
index f4782dded5..4c05acddf7 100644
--- a/lib/spack/external/_pytest/doctest.py
+++ b/lib/spack/external/_pytest/doctest.py
@@ -1,5 +1,5 @@
 """ discover and run doctests in modules and test files."""
-from __future__ import absolute_import
+from __future__ import absolute_import, division, print_function
 
 import traceback
 
@@ -22,27 +22,29 @@ DOCTEST_REPORT_CHOICES = (
     DOCTEST_REPORT_CHOICE_ONLY_FIRST_FAILURE,
 )
 
+
 def pytest_addoption(parser):
     parser.addini('doctest_optionflags', 'option flags for doctests',
-        type="args", default=["ELLIPSIS"])
+                  type="args", default=["ELLIPSIS"])
+    parser.addini("doctest_encoding", 'encoding used for doctest files', default="utf-8")
     group = parser.getgroup("collect")
     group.addoption("--doctest-modules",
-        action="store_true", default=False,
-        help="run doctests in all .py modules",
-        dest="doctestmodules")
+                    action="store_true", default=False,
+                    help="run doctests in all .py modules",
+                    dest="doctestmodules")
     group.addoption("--doctest-report",
-        type=str.lower, default="udiff",
-        help="choose another output format for diffs on doctest failure",
-        choices=DOCTEST_REPORT_CHOICES,
-        dest="doctestreport")
+                    type=str.lower, default="udiff",
+                    help="choose another output format for diffs on doctest failure",
+                    choices=DOCTEST_REPORT_CHOICES,
+                    dest="doctestreport")
     group.addoption("--doctest-glob",
-        action="append", default=[], metavar="pat",
-        help="doctests file matching pattern, default: test*.txt",
-        dest="doctestglob")
+                    action="append", default=[], metavar="pat",
+                    help="doctests file matching pattern, default: test*.txt",
+                    dest="doctestglob")
     group.addoption("--doctest-ignore-import-errors",
-        action="store_true", default=False,
-        help="ignore doctest ImportErrors",
-        dest="doctest_ignore_import_errors")
+                    action="store_true", default=False,
+                    help="ignore doctest ImportErrors",
+                    dest="doctest_ignore_import_errors")
 
 
 def pytest_collect_file(path, parent):
@@ -118,7 +120,7 @@ class DoctestItem(pytest.Item):
                 lines = ["%03d %s" % (i + test.lineno + 1, x)
                          for (i, x) in enumerate(lines)]
                 # trim docstring error lines to 10
-                lines = lines[example.lineno - 9:example.lineno + 1]
+                lines = lines[max(example.lineno - 9, 0):example.lineno + 1]
             else:
                 lines = ['EXAMPLE LOCATION UNKNOWN, not showing all tests of that example']
                 indent = '>>>'
@@ -127,18 +129,18 @@ class DoctestItem(pytest.Item):
                     indent = '...'
             if excinfo.errisinstance(doctest.DocTestFailure):
                 lines += checker.output_difference(example,
-                        doctestfailure.got, report_choice).split("\n")
+                                                   doctestfailure.got, report_choice).split("\n")
             else:
                 inner_excinfo = ExceptionInfo(excinfo.value.exc_info)
                 lines += ["UNEXPECTED EXCEPTION: %s" %
-                            repr(inner_excinfo.value)]
+                          repr(inner_excinfo.value)]
                 lines += traceback.format_exception(*excinfo.value.exc_info)
             return ReprFailDoctest(reprlocation, lines)
         else:
             return super(DoctestItem, self).repr_failure(excinfo)
 
     def reportinfo(self):
-        return self.fspath, None, "[doctest] %s" % self.name
+        return self.fspath, self.dtest.lineno, "[doctest] %s" % self.name
 
 
 def _get_flag_lookup():
@@ -171,15 +173,16 @@ class DoctestTextfile(pytest.Module):
 
         # inspired by doctest.testfile; ideally we would use it directly,
         # but it doesn't support passing a custom checker
-        text = self.fspath.read()
+        encoding = self.config.getini("doctest_encoding")
+        text = self.fspath.read_text(encoding)
         filename = str(self.fspath)
         name = self.fspath.basename
         globs = {'__name__': '__main__'}
 
-
         optionflags = get_optionflags(self)
         runner = doctest.DebugRunner(verbose=0, optionflags=optionflags,
                                      checker=_get_checker())
+        _fix_spoof_python2(runner, encoding)
 
         parser = doctest.DocTestParser()
         test = parser.get_doctest(text, globs, name, filename, 0)
@@ -215,6 +218,7 @@ class DoctestModule(pytest.Module):
         optionflags = get_optionflags(self)
         runner = doctest.DebugRunner(verbose=0, optionflags=optionflags,
                                      checker=_get_checker())
+
         for test in finder.find(module, module.__name__):
             if test.examples:  # skip empty doctests
                 yield DoctestItem(test.name, self, runner, test)
@@ -323,6 +327,33 @@ def _get_report_choice(key):
         DOCTEST_REPORT_CHOICE_NONE: 0,
     }[key]
 
+
+def _fix_spoof_python2(runner, encoding):
+    """
+    Installs a "SpoofOut" into the given DebugRunner so it properly deals with unicode output. This
+    should patch only doctests for text files because they don't have a way to declare their
+    encoding. Doctests in docstrings from Python modules don't have the same problem given that
+    Python already decoded the strings.
+
+    This fixes the problem related in issue #2434.
+    """
+    from _pytest.compat import _PY2
+    if not _PY2:
+        return
+
+    from doctest import _SpoofOut
+
+    class UnicodeSpoof(_SpoofOut):
+
+        def getvalue(self):
+            result = _SpoofOut.getvalue(self)
+            if encoding:
+                result = result.decode(encoding)
+            return result
+
+    runner._fakeout = UnicodeSpoof()
+
+
 @pytest.fixture(scope='session')
 def doctest_namespace():
     """
diff --git a/lib/spack/external/_pytest/fixtures.py b/lib/spack/external/_pytest/fixtures.py
index 28bcd4d8d7..b76ad50339 100644
--- a/lib/spack/external/_pytest/fixtures.py
+++ b/lib/spack/external/_pytest/fixtures.py
@@ -1,22 +1,39 @@
-import sys
+from __future__ import absolute_import, division, print_function
 
-from py._code.code import FormattedExcinfo
+import inspect
+import sys
+import warnings
 
 import py
-import pytest
-import warnings
+from py._code.code import FormattedExcinfo
 
-import inspect
 import _pytest
+from _pytest import nodes
 from _pytest._code.code import TerminalRepr
 from _pytest.compat import (
     NOTSET, exc_clear, _format_args,
     getfslineno, get_real_func,
     is_generator, isclass, getimfunc,
     getlocation, getfuncargnames,
+    safe_getattr,
+    FuncargnamesCompatAttr,
 )
+from _pytest.outcomes import fail, TEST_OUTCOME
+
+
+if sys.version_info[:2] == (2, 6):
+    from ordereddict import OrderedDict
+else:
+    from collections import OrderedDict  # nopyqver
+
 
 def pytest_sessionstart(session):
+    import _pytest.python
+    scopename2class.update({
+        'class': _pytest.python.Class,
+        'module': _pytest.python.Module,
+        'function': _pytest.main.Item,
+    })
     session._fixturemanager = FixtureManager(session)
 
 
@@ -29,6 +46,7 @@ scope2props["class"] = scope2props["module"] + ("cls",)
 scope2props["instance"] = scope2props["class"] + ("instance", )
 scope2props["function"] = scope2props["instance"] + ("function", "keywords")
 
+
 def scopeproperty(name=None, doc=None):
     def decoratescope(func):
         scopename = name or func.__name__
@@ -43,19 +61,6 @@ def scopeproperty(name=None, doc=None):
     return decoratescope
 
 
-def pytest_namespace():
-    scopename2class.update({
-        'class': pytest.Class,
-        'module': pytest.Module,
-        'function': pytest.Item,
-    })
-    return {
-        'fixture': fixture,
-        'yield_fixture': yield_fixture,
-        'collect': {'_fillfuncargs': fillfixtures}
-    }
-
-
 def get_scope_node(node, scope):
     cls = scopename2class.get(scope)
     if cls is None:
@@ -73,7 +78,7 @@ def add_funcarg_pseudo_fixture_def(collector, metafunc, fixturemanager):
     # XXX we can probably avoid this algorithm  if we modify CallSpec2
     # to directly care for creating the fixturedefs within its methods.
     if not metafunc._calls[0].funcargs:
-        return # this function call does not have direct parametrization
+        return  # this function call does not have direct parametrization
     # collect funcargs of all callspecs into a list of values
     arg2params = {}
     arg2scope = {}
@@ -103,36 +108,32 @@ def add_funcarg_pseudo_fixture_def(collector, metafunc, fixturemanager):
         if scope != "function":
             node = get_scope_node(collector, scope)
             if node is None:
-                assert scope == "class" and isinstance(collector, pytest.Module)
+                assert scope == "class" and isinstance(collector, _pytest.python.Module)
                 # use module-level collector for class-scope (for now)
                 node = collector
         if node and argname in node._name2pseudofixturedef:
             arg2fixturedefs[argname] = [node._name2pseudofixturedef[argname]]
         else:
-            fixturedef =  FixtureDef(fixturemanager, '', argname,
-                           get_direct_param_fixture_func,
-                           arg2scope[argname],
-                           valuelist, False, False)
+            fixturedef = FixtureDef(fixturemanager, '', argname,
+                                    get_direct_param_fixture_func,
+                                    arg2scope[argname],
+                                    valuelist, False, False)
             arg2fixturedefs[argname] = [fixturedef]
             if node is not None:
                 node._name2pseudofixturedef[argname] = fixturedef
 
 
-
 def getfixturemarker(obj):
     """ return fixturemarker or None if it doesn't exist or raised
     exceptions."""
     try:
         return getattr(obj, "_pytestfixturefunction", None)
-    except KeyboardInterrupt:
-        raise
-    except Exception:
+    except TEST_OUTCOME:
         # some objects raise errors like request (from flask import request)
         # we don't expect them to be fixture functions
         return None
 
 
-
 def get_parametrized_fixture_keys(item, scopenum):
     """ return list of keys for all parametrized arguments which match
     the specified scope. """
@@ -142,10 +143,10 @@ def get_parametrized_fixture_keys(item, scopenum):
     except AttributeError:
         pass
     else:
-        # cs.indictes.items() is random order of argnames but
-        # then again different functions (items) can change order of
-        # arguments so it doesn't matter much probably
-        for argname, param_index in cs.indices.items():
+        # cs.indices.items() is random order of argnames.  Need to
+        # sort this so that different calls to
+        # get_parametrized_fixture_keys will be deterministic.
+        for argname, param_index in sorted(cs.indices.items()):
             if cs._arg2scopenum[argname] != scopenum:
                 continue
             if scopenum == 0:    # session
@@ -167,20 +168,21 @@ def reorder_items(items):
     for scopenum in range(0, scopenum_function):
         argkeys_cache[scopenum] = d = {}
         for item in items:
-            keys = set(get_parametrized_fixture_keys(item, scopenum))
+            keys = OrderedDict.fromkeys(get_parametrized_fixture_keys(item, scopenum))
             if keys:
                 d[item] = keys
     return reorder_items_atscope(items, set(), argkeys_cache, 0)
 
+
 def reorder_items_atscope(items, ignore, argkeys_cache, scopenum):
     if scopenum >= scopenum_function or len(items) < 3:
         return items
     items_done = []
     while 1:
         items_before, items_same, items_other, newignore = \
-                slice_items(items, ignore, argkeys_cache[scopenum])
+            slice_items(items, ignore, argkeys_cache[scopenum])
         items_before = reorder_items_atscope(
-                            items_before, ignore, argkeys_cache,scopenum+1)
+            items_before, ignore, argkeys_cache, scopenum + 1)
         if items_same is None:
             # nothing to reorder in this scope
             assert items_other is None
@@ -201,9 +203,9 @@ def slice_items(items, ignore, scoped_argkeys_cache):
         for i, item in enumerate(it):
             argkeys = scoped_argkeys_cache.get(item)
             if argkeys is not None:
-                argkeys = argkeys.difference(ignore)
-                if argkeys:  # found a slicing key
-                    slicing_argkey = argkeys.pop()
+                newargkeys = OrderedDict.fromkeys(k for k in argkeys if k not in ignore)
+                if newargkeys:  # found a slicing key
+                    slicing_argkey, _ = newargkeys.popitem()
                     items_before = items[:i]
                     items_same = [item]
                     items_other = []
@@ -211,7 +213,7 @@ def slice_items(items, ignore, scoped_argkeys_cache):
                     for item in it:
                         argkeys = scoped_argkeys_cache.get(item)
                         if argkeys and slicing_argkey in argkeys and \
-                            slicing_argkey not in ignore:
+                                slicing_argkey not in ignore:
                             items_same.append(item)
                         else:
                             items_other.append(item)
@@ -221,17 +223,6 @@ def slice_items(items, ignore, scoped_argkeys_cache):
     return items, None, None, None
 
 
-
-class FuncargnamesCompatAttr:
-    """ helper class so that Metafunc, Function and FixtureRequest
-    don't need to each define the "funcargnames" compatibility attribute.
-    """
-    @property
-    def funcargnames(self):
-        """ alias attribute for ``fixturenames`` for pre-2.3 compatibility"""
-        return self.fixturenames
-
-
 def fillfixtures(function):
     """ fill missing funcargs for a test function. """
     try:
@@ -254,10 +245,10 @@ def fillfixtures(function):
         request._fillfixtures()
 
 
-
 def get_direct_param_fixture_func(request):
     return request.param
 
+
 class FuncFixtureInfo:
     def __init__(self, argnames, names_closure, name2fixturedefs):
         self.argnames = argnames
@@ -296,7 +287,6 @@ class FixtureRequest(FuncargnamesCompatAttr):
         """ underlying collection node (depends on current request scope)"""
         return self._getscopeitem(self.scope)
 
-
     def _getnextfixturedef(self, argname):
         fixturedefs = self._arg2fixturedefs.get(argname, None)
         if fixturedefs is None:
@@ -318,7 +308,6 @@ class FixtureRequest(FuncargnamesCompatAttr):
         """ the pytest config object associated with this request. """
         return self._pyfuncitem.config
 
-
     @scopeproperty()
     def function(self):
         """ test function object if the request has a per-function scope. """
@@ -327,7 +316,7 @@ class FixtureRequest(FuncargnamesCompatAttr):
     @scopeproperty("class")
     def cls(self):
         """ class (can be None) where the test function was collected. """
-        clscol = self._pyfuncitem.getparent(pytest.Class)
+        clscol = self._pyfuncitem.getparent(_pytest.python.Class)
         if clscol:
             return clscol.obj
 
@@ -345,7 +334,7 @@ class FixtureRequest(FuncargnamesCompatAttr):
     @scopeproperty()
     def module(self):
         """ python module object where the test function was collected. """
-        return self._pyfuncitem.getparent(pytest.Module).obj
+        return self._pyfuncitem.getparent(_pytest.python.Module).obj
 
     @scopeproperty()
     def fspath(self):
@@ -414,7 +403,7 @@ class FixtureRequest(FuncargnamesCompatAttr):
         :arg extrakey: added to internal caching key of (funcargname, scope).
         """
         if not hasattr(self.config, '_setupcache'):
-            self.config._setupcache = {} # XXX weakref?
+            self.config._setupcache = {}  # XXX weakref?
         cachekey = (self.fixturename, self._getscopeitem(scope), extrakey)
         cache = self.config._setupcache
         try:
@@ -445,7 +434,8 @@ class FixtureRequest(FuncargnamesCompatAttr):
         from _pytest import deprecated
         warnings.warn(
             deprecated.GETFUNCARGVALUE,
-            DeprecationWarning)
+            DeprecationWarning,
+            stacklevel=2)
         return self.getfixturevalue(argname)
 
     def _get_active_fixturedef(self, argname):
@@ -470,13 +460,13 @@ class FixtureRequest(FuncargnamesCompatAttr):
 
     def _get_fixturestack(self):
         current = self
-        l = []
+        values = []
         while 1:
             fixturedef = getattr(current, "_fixturedef", None)
             if fixturedef is None:
-                l.reverse()
-                return l
-            l.append(fixturedef)
+                values.reverse()
+                return values
+            values.append(fixturedef)
             current = current._parent_request
 
     def _getfixturevalue(self, fixturedef):
@@ -508,7 +498,7 @@ class FixtureRequest(FuncargnamesCompatAttr):
                         source_lineno,
                     )
                 )
-                pytest.fail(msg)
+                fail(msg)
         else:
             # indices might not be set if old-style metafunc.addcall() was used
             param_index = funcitem.callspec.indices.get(argname, 0)
@@ -541,11 +531,11 @@ class FixtureRequest(FuncargnamesCompatAttr):
         if scopemismatch(invoking_scope, requested_scope):
             # try to report something helpful
             lines = self._factorytraceback()
-            pytest.fail("ScopeMismatch: You tried to access the %r scoped "
-                "fixture %r with a %r scoped request object, "
-                "involved factories\n%s" %(
-                (requested_scope, argname, invoking_scope, "\n".join(lines))),
-                pytrace=False)
+            fail("ScopeMismatch: You tried to access the %r scoped "
+                 "fixture %r with a %r scoped request object, "
+                 "involved factories\n%s" % (
+                     (requested_scope, argname, invoking_scope, "\n".join(lines))),
+                 pytrace=False)
 
     def _factorytraceback(self):
         lines = []
@@ -554,7 +544,7 @@ class FixtureRequest(FuncargnamesCompatAttr):
             fs, lineno = getfslineno(factory)
             p = self._pyfuncitem.session.fspath.bestrelpath(fs)
             args = _format_args(factory)
-            lines.append("%s:%d:  def %s%s" %(
+            lines.append("%s:%d:  def %s%s" % (
                 p, lineno, factory.__name__, args))
         return lines
 
@@ -570,12 +560,13 @@ class FixtureRequest(FuncargnamesCompatAttr):
         return node
 
     def __repr__(self):
-        return "<FixtureRequest for %r>" %(self.node)
+        return "<FixtureRequest for %r>" % (self.node)
 
 
 class SubRequest(FixtureRequest):
     """ a sub request for handling getting a fixture from a
     test function/fixture. """
+
     def __init__(self, request, scope, param, param_index, fixturedef):
         self._parent_request = request
         self.fixturename = fixturedef.argname
@@ -584,9 +575,8 @@ class SubRequest(FixtureRequest):
         self.param_index = param_index
         self.scope = scope
         self._fixturedef = fixturedef
-        self.addfinalizer = fixturedef.addfinalizer
         self._pyfuncitem = request._pyfuncitem
-        self._fixture_values  = request._fixture_values
+        self._fixture_values = request._fixture_values
         self._fixture_defs = request._fixture_defs
         self._arg2fixturedefs = request._arg2fixturedefs
         self._arg2index = request._arg2index
@@ -595,6 +585,9 @@ class SubRequest(FixtureRequest):
     def __repr__(self):
         return "<SubRequest %r for %r>" % (self.fixturename, self._pyfuncitem)
 
+    def addfinalizer(self, finalizer):
+        self._fixturedef.addfinalizer(finalizer)
+
 
 class ScopeMismatchError(Exception):
     """ A fixture function tries to use a different fixture function which
@@ -626,6 +619,7 @@ def scope2index(scope, descr, where=None):
 
 class FixtureLookupError(LookupError):
     """ could not return a requested Fixture (missing or invalid). """
+
     def __init__(self, argname, request, msg=None):
         self.argname = argname
         self.request = request
@@ -648,9 +642,9 @@ class FixtureLookupError(LookupError):
                 lines, _ = inspect.getsourcelines(get_real_func(function))
             except (IOError, IndexError, TypeError):
                 error_msg = "file %s, line %s: source code not available"
-                addline(error_msg % (fspath, lineno+1))
+                addline(error_msg % (fspath, lineno + 1))
             else:
-                addline("file %s, line %s" % (fspath, lineno+1))
+                addline("file %s, line %s" % (fspath, lineno + 1))
                 for i, line in enumerate(lines):
                     line = line.rstrip()
                     addline("  " + line)
@@ -666,7 +660,7 @@ class FixtureLookupError(LookupError):
                 if faclist and name not in available:
                     available.append(name)
             msg = "fixture %r not found" % (self.argname,)
-            msg += "\n available fixtures: %s" %(", ".join(sorted(available)),)
+            msg += "\n available fixtures: %s" % (", ".join(sorted(available)),)
             msg += "\n use 'pytest --fixtures [testpath]' for help on them."
 
         return FixtureLookupErrorRepr(fspath, lineno, tblines, msg, self.argname)
@@ -692,15 +686,16 @@ class FixtureLookupErrorRepr(TerminalRepr):
                 tw.line('{0}       {1}'.format(FormattedExcinfo.flow_marker,
                                                line.strip()), red=True)
         tw.line()
-        tw.line("%s:%d" % (self.filename, self.firstlineno+1))
+        tw.line("%s:%d" % (self.filename, self.firstlineno + 1))
 
 
 def fail_fixturefunc(fixturefunc, msg):
     fs, lineno = getfslineno(fixturefunc)
-    location = "%s:%s" % (fs, lineno+1)
+    location = "%s:%s" % (fs, lineno + 1)
     source = _pytest._code.Source(fixturefunc)
-    pytest.fail(msg + ":\n\n" + str(source.indent()) + "\n" + location,
-                pytrace=False)
+    fail(msg + ":\n\n" + str(source.indent()) + "\n" + location,
+         pytrace=False)
+
 
 def call_fixture_func(fixturefunc, request, kwargs):
     yieldctx = is_generator(fixturefunc)
@@ -715,7 +710,7 @@ def call_fixture_func(fixturefunc, request, kwargs):
                 pass
             else:
                 fail_fixturefunc(fixturefunc,
-                    "yield_fixture function has more than one 'yield'")
+                                 "yield_fixture function has more than one 'yield'")
 
         request.addfinalizer(teardown)
     else:
@@ -725,6 +720,7 @@ def call_fixture_func(fixturefunc, request, kwargs):
 
 class FixtureDef:
     """ A container for a factory definition. """
+
     def __init__(self, fixturemanager, baseid, argname, func, scope, params,
                  unittest=False, ids=None):
         self._fixturemanager = fixturemanager
@@ -749,10 +745,19 @@ class FixtureDef:
         self._finalizer.append(finalizer)
 
     def finish(self):
+        exceptions = []
         try:
             while self._finalizer:
-                func = self._finalizer.pop()
-                func()
+                try:
+                    func = self._finalizer.pop()
+                    func()
+                except:  # noqa
+                    exceptions.append(sys.exc_info())
+            if exceptions:
+                e = exceptions[0]
+                del exceptions  # ensure we don't keep all frames alive because of the traceback
+                py.builtin._reraise(*e)
+
         finally:
             ihook = self._fixturemanager.session.ihook
             ihook.pytest_fixture_post_finalizer(fixturedef=self)
@@ -790,6 +795,7 @@ class FixtureDef:
         return ("<FixtureDef name=%r scope=%r baseid=%r >" %
                 (self.argname, self.scope, self.baseid))
 
+
 def pytest_fixture_setup(fixturedef, request):
     """ Execution of fixture setup. """
     kwargs = {}
@@ -815,7 +821,7 @@ def pytest_fixture_setup(fixturedef, request):
     my_cache_key = request.param_index
     try:
         result = call_fixture_func(fixturefunc, request, kwargs)
-    except Exception:
+    except TEST_OUTCOME:
         fixturedef.cached_result = (None, my_cache_key, sys.exc_info())
         raise
     fixturedef.cached_result = (result, my_cache_key, None)
@@ -833,17 +839,16 @@ class FixtureFunctionMarker:
     def __call__(self, function):
         if isclass(function):
             raise ValueError(
-                    "class fixtures not supported (may be in the future)")
+                "class fixtures not supported (may be in the future)")
         function._pytestfixturefunction = self
         return function
 
 
-
 def fixture(scope="function", params=None, autouse=False, ids=None, name=None):
     """ (return a) decorator to mark a fixture factory function.
 
-    This decorator can be used (with or or without parameters) to define
-    a fixture function.  The name of the fixture function can later be
+    This decorator can be used (with or without parameters) to define a
+    fixture function.  The name of the fixture function can later be
     referenced to cause its invocation ahead of running tests: test
     modules or classes can use the pytest.mark.usefixtures(fixturename)
     marker.  Test functions can directly use fixture names as input
@@ -862,25 +867,25 @@ def fixture(scope="function", params=None, autouse=False, ids=None, name=None):
                 reference is needed to activate the fixture.
 
     :arg ids: list of string ids each corresponding to the params
-       so that they are part of the test id. If no ids are provided
-       they will be generated automatically from the params.
+                so that they are part of the test id. If no ids are provided
+                they will be generated automatically from the params.
 
     :arg name: the name of the fixture. This defaults to the name of the
-               decorated function. If a fixture is used in the same module in
-               which it is defined, the function name of the fixture will be
-               shadowed by the function arg that requests the fixture; one way
-               to resolve this is to name the decorated function
-               ``fixture_<fixturename>`` and then use
-               ``@pytest.fixture(name='<fixturename>')``.
+                decorated function. If a fixture is used in the same module in
+                which it is defined, the function name of the fixture will be
+                shadowed by the function arg that requests the fixture; one way
+                to resolve this is to name the decorated function
+                ``fixture_<fixturename>`` and then use
+                ``@pytest.fixture(name='<fixturename>')``.
 
     Fixtures can optionally provide their values to test functions using a ``yield`` statement,
     instead of ``return``. In this case, the code block after the ``yield`` statement is executed
     as teardown code regardless of the test outcome. A fixture function must yield exactly once.
     """
-    if callable(scope) and params is None and autouse == False:
+    if callable(scope) and params is None and autouse is False:
         # direct decoration
         return FixtureFunctionMarker(
-                "function", params, autouse, name=name)(scope)
+            "function", params, autouse, name=name)(scope)
     if params is not None and not isinstance(params, (list, tuple)):
         params = list(params)
     return FixtureFunctionMarker(scope, params, autouse, ids=ids, name=name)
@@ -895,7 +900,7 @@ def yield_fixture(scope="function", params=None, autouse=False, ids=None, name=N
     if callable(scope) and params is None and not autouse:
         # direct decoration
         return FixtureFunctionMarker(
-                "function", params, autouse, ids=ids, name=name)(scope)
+            "function", params, autouse, ids=ids, name=name)(scope)
     else:
         return FixtureFunctionMarker(scope, params, autouse, ids=ids, name=name)
 
@@ -954,14 +959,9 @@ class FixtureManager:
         self._nodeid_and_autousenames = [("", self.config.getini("usefixtures"))]
         session.config.pluginmanager.register(self, "funcmanage")
 
-
     def getfixtureinfo(self, node, func, cls, funcargs=True):
         if funcargs and not hasattr(node, "nofuncargs"):
-            if cls is not None:
-                startindex = 1
-            else:
-                startindex = None
-            argnames = getfuncargnames(func, startindex)
+            argnames = getfuncargnames(func, cls=cls)
         else:
             argnames = ()
         usefixtures = getattr(func, "usefixtures", None)
@@ -985,8 +985,8 @@ class FixtureManager:
             # by their test id)
             if p.basename.startswith("conftest.py"):
                 nodeid = p.dirpath().relto(self.config.rootdir)
-                if p.sep != "/":
-                    nodeid = nodeid.replace(p.sep, "/")
+                if p.sep != nodes.SEP:
+                    nodeid = nodeid.replace(p.sep, nodes.SEP)
         self.parsefactories(plugin, nodeid)
 
     def _getautousenames(self, nodeid):
@@ -996,7 +996,7 @@ class FixtureManager:
             if nodeid.startswith(baseid):
                 if baseid:
                     i = len(baseid)
-                    nextchar = nodeid[i:i+1]
+                    nextchar = nodeid[i:i + 1]
                     if nextchar and nextchar not in ":/":
                         continue
                 autousenames.extend(basenames)
@@ -1041,9 +1041,14 @@ class FixtureManager:
             if faclist:
                 fixturedef = faclist[-1]
                 if fixturedef.params is not None:
-                    func_params = getattr(getattr(metafunc.function, 'parametrize', None), 'args', [[None]])
+                    parametrize_func = getattr(metafunc.function, 'parametrize', None)
+                    func_params = getattr(parametrize_func, 'args', [[None]])
+                    func_kwargs = getattr(parametrize_func, 'kwargs', {})
                     # skip directly parametrized arguments
-                    argnames = func_params[0]
+                    if "argnames" in func_kwargs:
+                        argnames = parametrize_func.kwargs["argnames"]
+                    else:
+                        argnames = func_params[0]
                     if not isinstance(argnames, (tuple, list)):
                         argnames = [x.strip() for x in argnames.split(",") if x.strip()]
                     if argname not in func_params and argname not in argnames:
@@ -1068,7 +1073,9 @@ class FixtureManager:
         self._holderobjseen.add(holderobj)
         autousenames = []
         for name in dir(holderobj):
-            obj = getattr(holderobj, name, None)
+            # The attribute can be an arbitrary descriptor, so the attribute
+            # access below can raise. safe_getatt() ignores such exceptions.
+            obj = safe_getattr(holderobj, name, None)
             # fixture functions have a pytest_funcarg__ prefix (pre-2.3 style)
             # or are "@pytest.fixture" marked
             marker = getfixturemarker(obj)
@@ -1079,7 +1086,7 @@ class FixtureManager:
                     continue
                 marker = defaultfuncargprefixmarker
                 from _pytest import deprecated
-                self.config.warn('C1', deprecated.FUNCARG_PREFIX.format(name=name))
+                self.config.warn('C1', deprecated.FUNCARG_PREFIX.format(name=name), nodeid=nodeid)
                 name = name[len(self._argprefix):]
             elif not isinstance(marker, FixtureFunctionMarker):
                 # magic globals  with __getattr__ might have got us a wrong
@@ -1129,6 +1136,5 @@ class FixtureManager:
 
     def _matchfactories(self, fixturedefs, nodeid):
         for fixturedef in fixturedefs:
-            if nodeid.startswith(fixturedef.baseid):
+            if nodes.ischildnode(fixturedef.baseid, nodeid):
                 yield fixturedef
-
diff --git a/lib/spack/external/_pytest/freeze_support.py b/lib/spack/external/_pytest/freeze_support.py
index b27f59d74a..97147a8825 100644
--- a/lib/spack/external/_pytest/freeze_support.py
+++ b/lib/spack/external/_pytest/freeze_support.py
@@ -2,9 +2,7 @@
 Provides a function to report all internal modules for using freezing tools
 pytest
 """
-
-def pytest_namespace():
-    return {'freeze_includes': freeze_includes}
+from __future__ import absolute_import, division, print_function
 
 
 def freeze_includes():
diff --git a/lib/spack/external/_pytest/helpconfig.py b/lib/spack/external/_pytest/helpconfig.py
index 6e66b11c48..e744637f86 100644
--- a/lib/spack/external/_pytest/helpconfig.py
+++ b/lib/spack/external/_pytest/helpconfig.py
@@ -1,25 +1,61 @@
 """ version info, help messages, tracing configuration.  """
+from __future__ import absolute_import, division, print_function
+
 import py
 import pytest
-import os, sys
+from _pytest.config import PrintHelp
+import os
+import sys
+from argparse import Action
+
+
+class HelpAction(Action):
+    """This is an argparse Action that will raise an exception in
+    order to skip the rest of the argument parsing when --help is passed.
+    This prevents argparse from quitting due to missing required arguments
+    when any are defined, for example by ``pytest_addoption``.
+    This is similar to the way that the builtin argparse --help option is
+    implemented by raising SystemExit.
+    """
+
+    def __init__(self,
+                 option_strings,
+                 dest=None,
+                 default=False,
+                 help=None):
+        super(HelpAction, self).__init__(
+            option_strings=option_strings,
+            dest=dest,
+            const=True,
+            default=default,
+            nargs=0,
+            help=help)
+
+    def __call__(self, parser, namespace, values, option_string=None):
+        setattr(namespace, self.dest, self.const)
+
+        # We should only skip the rest of the parsing after preparse is done
+        if getattr(parser._parser, 'after_preparse', False):
+            raise PrintHelp
+
 
 def pytest_addoption(parser):
     group = parser.getgroup('debugconfig')
     group.addoption('--version', action="store_true",
-            help="display pytest lib version and import information.")
-    group._addoption("-h", "--help", action="store_true", dest="help",
-            help="show help message and configuration info")
-    group._addoption('-p', action="append", dest="plugins", default = [],
-               metavar="name",
-               help="early-load given plugin (multi-allowed). "
-                    "To avoid loading of plugins, use the `no:` prefix, e.g. "
-                    "`no:doctest`.")
+                    help="display pytest lib version and import information.")
+    group._addoption("-h", "--help", action=HelpAction, dest="help",
+                     help="show help message and configuration info")
+    group._addoption('-p', action="append", dest="plugins", default=[],
+                     metavar="name",
+                     help="early-load given plugin (multi-allowed). "
+                     "To avoid loading of plugins, use the `no:` prefix, e.g. "
+                     "`no:doctest`.")
     group.addoption('--traceconfig', '--trace-config',
-               action="store_true", default=False,
-               help="trace considerations of conftest.py files."),
+                    action="store_true", default=False,
+                    help="trace considerations of conftest.py files."),
     group.addoption('--debug',
-               action="store_true", dest="debug", default=False,
-               help="store internal tracing debug information in 'pytestdebug.log'.")
+                    action="store_true", dest="debug", default=False,
+                    help="store internal tracing debug information in 'pytestdebug.log'.")
     group._addoption(
         '-o', '--override-ini', nargs='*', dest="override_ini",
         action="append",
@@ -34,10 +70,10 @@ def pytest_cmdline_parse():
         path = os.path.abspath("pytestdebug.log")
         debugfile = open(path, 'w')
         debugfile.write("versions pytest-%s, py-%s, "
-                "python-%s\ncwd=%s\nargs=%s\n\n" %(
-            pytest.__version__, py.__version__,
-            ".".join(map(str, sys.version_info)),
-            os.getcwd(), config._origargs))
+                        "python-%s\ncwd=%s\nargs=%s\n\n" % (
+                            pytest.__version__, py.__version__,
+                            ".".join(map(str, sys.version_info)),
+                            os.getcwd(), config._origargs))
         config.trace.root.setwriter(debugfile.write)
         undo_tracing = config.pluginmanager.enable_tracing()
         sys.stderr.write("writing pytestdebug information to %s\n" % path)
@@ -51,11 +87,12 @@ def pytest_cmdline_parse():
 
         config.add_cleanup(unset_tracing)
 
+
 def pytest_cmdline_main(config):
     if config.option.version:
         p = py.path.local(pytest.__file__)
         sys.stderr.write("This is pytest version %s, imported from %s\n" %
-            (pytest.__version__, p))
+                         (pytest.__version__, p))
         plugininfo = getpluginversioninfo(config)
         if plugininfo:
             for line in plugininfo:
@@ -67,6 +104,7 @@ def pytest_cmdline_main(config):
         config._ensure_unconfigure()
         return 0
 
+
 def showhelp(config):
     reporter = config.pluginmanager.get_plugin('terminalreporter')
     tw = reporter._tw
@@ -82,7 +120,7 @@ def showhelp(config):
         if type is None:
             type = "string"
         spec = "%s (%s)" % (name, type)
-        line = "  %-24s %s" %(spec, help)
+        line = "  %-24s %s" % (spec, help)
         tw.line(line[:tw.fullwidth])
 
     tw.line()
@@ -111,6 +149,7 @@ conftest_options = [
     ('pytest_plugins', 'list of plugin names to load'),
 ]
 
+
 def getpluginversioninfo(config):
     lines = []
     plugininfo = config.pluginmanager.list_plugin_distinfo()
@@ -122,11 +161,12 @@ def getpluginversioninfo(config):
             lines.append("  " + content)
     return lines
 
+
 def pytest_report_header(config):
     lines = []
     if config.option.debug or config.option.traceconfig:
         lines.append("using: pytest-%s pylib-%s" %
-            (pytest.__version__,py.__version__))
+                     (pytest.__version__, py.__version__))
 
         verinfo = getpluginversioninfo(config)
         if verinfo:
@@ -140,5 +180,5 @@ def pytest_report_header(config):
                 r = plugin.__file__
             else:
                 r = repr(plugin)
-            lines.append("    %-20s: %s" %(name, r))
+            lines.append("    %-20s: %s" % (name, r))
     return lines
diff --git a/lib/spack/external/_pytest/hookspec.py b/lib/spack/external/_pytest/hookspec.py
index b5f51eccf5..e5c966e58b 100644
--- a/lib/spack/external/_pytest/hookspec.py
+++ b/lib/spack/external/_pytest/hookspec.py
@@ -8,6 +8,7 @@ hookspec = HookspecMarker("pytest")
 # Initialization hooks called for every plugin
 # -------------------------------------------------------------------------
 
+
 @hookspec(historic=True)
 def pytest_addhooks(pluginmanager):
     """called at plugin registration time to allow adding new hooks via a call to
@@ -16,11 +17,14 @@ def pytest_addhooks(pluginmanager):
 
 @hookspec(historic=True)
 def pytest_namespace():
-    """return dict of name->object to be made globally available in
+    """
+    DEPRECATED: this hook causes direct monkeypatching on pytest, its use is strongly discouraged
+    return dict of name->object to be made globally available in
     the pytest namespace.  This hook is called at plugin registration
     time.
     """
 
+
 @hookspec(historic=True)
 def pytest_plugin_registered(plugin, manager):
     """ a new pytest plugin got registered. """
@@ -56,11 +60,20 @@ def pytest_addoption(parser):
     via (deprecated) ``pytest.config``.
     """
 
+
 @hookspec(historic=True)
 def pytest_configure(config):
-    """ called after command line options have been parsed
-    and all plugins and initial conftest files been loaded.
-    This hook is called for every plugin.
+    """
+    Allows plugins and conftest files to perform initial configuration.
+
+    This hook is called for every plugin and initial conftest file
+    after command line options have been parsed.
+
+    After that, the hook is called for other conftest files as they are
+    imported.
+
+    :arg config: pytest config object
+    :type config: _pytest.config.Config
     """
 
 # -------------------------------------------------------------------------
@@ -69,17 +82,25 @@ def pytest_configure(config):
 # discoverable conftest.py local plugins.
 # -------------------------------------------------------------------------
 
+
 @hookspec(firstresult=True)
 def pytest_cmdline_parse(pluginmanager, args):
-    """return initialized config object, parsing the specified args. """
+    """return initialized config object, parsing the specified args.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 def pytest_cmdline_preparse(config, args):
     """(deprecated) modify command line arguments before option parsing. """
 
+
 @hookspec(firstresult=True)
 def pytest_cmdline_main(config):
     """ called for performing the main command line action. The default
-    implementation will invoke the configure hooks and runtest_mainloop. """
+    implementation will invoke the configure hooks and runtest_mainloop.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 def pytest_load_initial_conftests(early_config, parser, args):
     """ implements the loading of initial conftest files ahead
@@ -92,88 +113,124 @@ def pytest_load_initial_conftests(early_config, parser, args):
 
 @hookspec(firstresult=True)
 def pytest_collection(session):
-    """ perform the collection protocol for the given session. """
+    """ perform the collection protocol for the given session.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 def pytest_collection_modifyitems(session, config, items):
     """ called after collection has been performed, may filter or re-order
     the items in-place."""
 
+
 def pytest_collection_finish(session):
     """ called after collection has been performed and modified. """
 
+
 @hookspec(firstresult=True)
 def pytest_ignore_collect(path, config):
     """ return True to prevent considering this path for collection.
     This hook is consulted for all files and directories prior to calling
     more specific hooks.
+
+    Stops at first non-None result, see :ref:`firstresult`
     """
 
+
 @hookspec(firstresult=True)
 def pytest_collect_directory(path, parent):
-    """ called before traversing a directory for collection files. """
+    """ called before traversing a directory for collection files.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 def pytest_collect_file(path, parent):
     """ return collection Node or None for the given path. Any new node
     needs to have the specified ``parent`` as a parent."""
 
 # logging hooks for collection
+
+
 def pytest_collectstart(collector):
     """ collector starts collecting. """
 
+
 def pytest_itemcollected(item):
     """ we just collected a test item. """
 
+
 def pytest_collectreport(report):
     """ collector finished collecting. """
 
+
 def pytest_deselected(items):
     """ called for test items deselected by keyword. """
 
+
 @hookspec(firstresult=True)
 def pytest_make_collect_report(collector):
-    """ perform ``collector.collect()`` and return a CollectReport. """
+    """ perform ``collector.collect()`` and return a CollectReport.
+
+    Stops at first non-None result, see :ref:`firstresult` """
 
 # -------------------------------------------------------------------------
 # Python test function related hooks
 # -------------------------------------------------------------------------
 
+
 @hookspec(firstresult=True)
 def pytest_pycollect_makemodule(path, parent):
     """ return a Module collector or None for the given path.
     This hook will be called for each matching test module path.
     The pytest_collect_file hook needs to be used if you want to
     create test modules for files that do not match as a test module.
-    """
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 @hookspec(firstresult=True)
 def pytest_pycollect_makeitem(collector, name, obj):
-    """ return custom item/collector for a python object in a module, or None.  """
+    """ return custom item/collector for a python object in a module, or None.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 @hookspec(firstresult=True)
 def pytest_pyfunc_call(pyfuncitem):
-    """ call underlying test function. """
+    """ call underlying test function.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 def pytest_generate_tests(metafunc):
     """ generate (multiple) parametrized calls to a test function."""
 
+
 @hookspec(firstresult=True)
-def pytest_make_parametrize_id(config, val):
+def pytest_make_parametrize_id(config, val, argname):
     """Return a user-friendly string representation of the given ``val`` that will be used
     by @pytest.mark.parametrize calls. Return None if the hook doesn't know about ``val``.
-    """
+    The parameter name is available as ``argname``, if required.
+
+    Stops at first non-None result, see :ref:`firstresult` """
 
 # -------------------------------------------------------------------------
 # generic runtest related hooks
 # -------------------------------------------------------------------------
 
+
 @hookspec(firstresult=True)
 def pytest_runtestloop(session):
     """ called for performing the main runtest loop
-    (after collection finished). """
+    (after collection finished).
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 def pytest_itemstart(item, node):
     """ (deprecated, use pytest_runtest_logstart). """
 
+
 @hookspec(firstresult=True)
 def pytest_runtest_protocol(item, nextitem):
     """ implements the runtest_setup/call/teardown protocol for
@@ -187,17 +244,23 @@ def pytest_runtest_protocol(item, nextitem):
                    :py:func:`pytest_runtest_teardown`.
 
     :return boolean: True if no further hook implementations should be invoked.
-    """
+
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 def pytest_runtest_logstart(nodeid, location):
     """ signal the start of running a single test item. """
 
+
 def pytest_runtest_setup(item):
     """ called before ``pytest_runtest_call(item)``. """
 
+
 def pytest_runtest_call(item):
     """ called to execute the test ``item``. """
 
+
 def pytest_runtest_teardown(item, nextitem):
     """ called after ``pytest_runtest_call``.
 
@@ -207,12 +270,15 @@ def pytest_runtest_teardown(item, nextitem):
                    so that nextitem only needs to call setup-functions.
     """
 
+
 @hookspec(firstresult=True)
 def pytest_runtest_makereport(item, call):
     """ return a :py:class:`_pytest.runner.TestReport` object
-    for the given :py:class:`pytest.Item` and
+    for the given :py:class:`pytest.Item <_pytest.main.Item>` and
     :py:class:`_pytest.runner.CallInfo`.
-    """
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 def pytest_runtest_logreport(report):
     """ process a test setup/call/teardown report relating to
@@ -222,9 +288,13 @@ def pytest_runtest_logreport(report):
 # Fixture related hooks
 # -------------------------------------------------------------------------
 
+
 @hookspec(firstresult=True)
 def pytest_fixture_setup(fixturedef, request):
-    """ performs fixture setup execution. """
+    """ performs fixture setup execution.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 def pytest_fixture_post_finalizer(fixturedef):
     """ called after fixture teardown, but before the cache is cleared so
@@ -235,18 +305,21 @@ def pytest_fixture_post_finalizer(fixturedef):
 # test session related hooks
 # -------------------------------------------------------------------------
 
+
 def pytest_sessionstart(session):
     """ before session.main() is called. """
 
+
 def pytest_sessionfinish(session, exitstatus):
     """ whole test run finishes. """
 
+
 def pytest_unconfigure(config):
     """ called before test process is exited.  """
 
 
 # -------------------------------------------------------------------------
-# hooks for customising the assert methods
+# hooks for customizing the assert methods
 # -------------------------------------------------------------------------
 
 def pytest_assertrepr_compare(config, op, left, right):
@@ -255,19 +328,48 @@ def pytest_assertrepr_compare(config, op, left, right):
     Return None for no custom explanation, otherwise return a list
     of strings.  The strings will be joined by newlines but any newlines
     *in* a string will be escaped.  Note that all but the first line will
-    be indented sligthly, the intention is for the first line to be a summary.
+    be indented slightly, the intention is for the first line to be a summary.
     """
 
 # -------------------------------------------------------------------------
 # hooks for influencing reporting (invoked from _pytest_terminal)
 # -------------------------------------------------------------------------
 
+
 def pytest_report_header(config, startdir):
-    """ return a string to be displayed as header info for terminal reporting."""
+    """ return a string or list of strings to be displayed as header info for terminal reporting.
+
+    :param config: the pytest config object.
+    :param startdir: py.path object with the starting dir
+
+    .. note::
+
+        This function should be implemented only in plugins or ``conftest.py``
+        files situated at the tests root directory due to how pytest
+        :ref:`discovers plugins during startup <pluginorder>`.
+    """
+
+
+def pytest_report_collectionfinish(config, startdir, items):
+    """
+    .. versionadded:: 3.2
+
+    return a string or list of strings to be displayed after collection has finished successfully.
+
+    This strings will be displayed after the standard "collected X items" message.
+
+    :param config: the pytest config object.
+    :param startdir: py.path object with the starting dir
+    :param items: list of pytest items that are going to be executed; this list should not be modified.
+    """
+
 
 @hookspec(firstresult=True)
 def pytest_report_teststatus(report):
-    """ return result-category, shortletter and verbose word for reporting."""
+    """ return result-category, shortletter and verbose word for reporting.
+
+    Stops at first non-None result, see :ref:`firstresult` """
+
 
 def pytest_terminal_summary(terminalreporter, exitstatus):
     """ add additional section in terminal summary reporting.  """
@@ -283,20 +385,26 @@ def pytest_logwarning(message, code, nodeid, fslocation):
 # doctest hooks
 # -------------------------------------------------------------------------
 
+
 @hookspec(firstresult=True)
 def pytest_doctest_prepare_content(content):
-    """ return processed content for a given doctest"""
+    """ return processed content for a given doctest
+
+    Stops at first non-None result, see :ref:`firstresult` """
 
 # -------------------------------------------------------------------------
 # error handling and internal debugging hooks
 # -------------------------------------------------------------------------
 
+
 def pytest_internalerror(excrepr, excinfo):
     """ called for internal errors. """
 
+
 def pytest_keyboard_interrupt(excinfo):
     """ called for keyboard interrupt. """
 
+
 def pytest_exception_interact(node, call, report):
     """called when an exception was raised which can potentially be
     interactively handled.
@@ -305,6 +413,7 @@ def pytest_exception_interact(node, call, report):
     that is not an internal exception like ``skip.Exception``.
     """
 
+
 def pytest_enter_pdb(config):
     """ called upon pdb.set_trace(), can be used by plugins to take special
     action just before the python debugger enters in interactive mode.
diff --git a/lib/spack/external/_pytest/junitxml.py b/lib/spack/external/_pytest/junitxml.py
index 317382e637..7fb40dc354 100644
--- a/lib/spack/external/_pytest/junitxml.py
+++ b/lib/spack/external/_pytest/junitxml.py
@@ -4,9 +4,11 @@
 
 
 Based on initial code from Ross Lawley.
+
+Output conforms to https://github.com/jenkinsci/xunit-plugin/blob/master/
+src/main/resources/org/jenkinsci/plugins/xunit/types/model/xsd/junit-10.xsd
 """
-# Output conforms to https://github.com/jenkinsci/xunit-plugin/blob/master/
-# src/main/resources/org/jenkinsci/plugins/xunit/types/model/xsd/junit-10.xsd
+from __future__ import absolute_import, division, print_function
 
 import functools
 import py
@@ -15,6 +17,7 @@ import re
 import sys
 import time
 import pytest
+from _pytest import nodes
 from _pytest.config import filename_arg
 
 # Python 2.X and 3.X compatibility
@@ -105,6 +108,8 @@ class _NodeReporter(object):
         }
         if testreport.location[1] is not None:
             attrs["line"] = testreport.location[1]
+        if hasattr(testreport, "url"):
+            attrs["url"] = testreport.url
         self.attrs = attrs
 
     def to_xml(self):
@@ -119,7 +124,7 @@ class _NodeReporter(object):
         node = kind(data, message=message)
         self.append(node)
 
-    def _write_captured_output(self, report):
+    def write_captured_output(self, report):
         for capname in ('out', 'err'):
             content = getattr(report, 'capstd' + capname)
             if content:
@@ -128,7 +133,6 @@ class _NodeReporter(object):
 
     def append_pass(self, report):
         self.add_stats('passed')
-        self._write_captured_output(report)
 
     def append_failure(self, report):
         # msg = str(report.longrepr.reprtraceback.extraline)
@@ -147,7 +151,6 @@ class _NodeReporter(object):
             fail = Junit.failure(message=message)
             fail.append(bin_xml_escape(report.longrepr))
             self.append(fail)
-        self._write_captured_output(report)
 
     def append_collect_error(self, report):
         # msg = str(report.longrepr.reprtraceback.extraline)
@@ -165,7 +168,6 @@ class _NodeReporter(object):
             msg = "test setup failure"
         self._add_simple(
             Junit.error, msg, report.longrepr)
-        self._write_captured_output(report)
 
     def append_skipped(self, report):
         if hasattr(report, "wasxfail"):
@@ -180,7 +182,7 @@ class _NodeReporter(object):
                 Junit.skipped("%s:%s: %s" % (filename, lineno, skipreason),
                               type="pytest.skip",
                               message=skipreason))
-        self._write_captured_output(report)
+        self.write_captured_output(report)
 
     def finalize(self):
         data = self.to_xml().unicode(indent=0)
@@ -225,13 +227,14 @@ def pytest_addoption(parser):
         metavar="str",
         default=None,
         help="prepend prefix to classnames in junit-xml output")
+    parser.addini("junit_suite_name", "Test suite name for JUnit report", default="pytest")
 
 
 def pytest_configure(config):
     xmlpath = config.option.xmlpath
     # prevent opening xmllog on slave nodes (xdist)
     if xmlpath and not hasattr(config, 'slaveinput'):
-        config._xml = LogXML(xmlpath, config.option.junitprefix)
+        config._xml = LogXML(xmlpath, config.option.junitprefix, config.getini("junit_suite_name"))
         config.pluginmanager.register(config._xml)
 
 
@@ -250,7 +253,7 @@ def mangle_test_address(address):
     except ValueError:
         pass
     # convert file path to dotted path
-    names[0] = names[0].replace("/", '.')
+    names[0] = names[0].replace(nodes.SEP, '.')
     names[0] = _py_ext_re.sub("", names[0])
     # put any params back
     names[-1] += possible_open_bracket + params
@@ -258,10 +261,11 @@ def mangle_test_address(address):
 
 
 class LogXML(object):
-    def __init__(self, logfile, prefix):
+    def __init__(self, logfile, prefix, suite_name="pytest"):
         logfile = os.path.expanduser(os.path.expandvars(logfile))
         self.logfile = os.path.normpath(os.path.abspath(logfile))
         self.prefix = prefix
+        self.suite_name = suite_name
         self.stats = dict.fromkeys([
             'error',
             'passed',
@@ -271,6 +275,9 @@ class LogXML(object):
         self.node_reporters = {}  # nodeid -> _NodeReporter
         self.node_reporters_ordered = []
         self.global_properties = []
+        # List of reports that failed on call but teardown is pending.
+        self.open_reports = []
+        self.cnt_double_fail_tests = 0
 
     def finalize(self, report):
         nodeid = getattr(report, 'nodeid', report)
@@ -330,14 +337,33 @@ class LogXML(object):
             -> teardown node2
             -> teardown node1
         """
+        close_report = None
         if report.passed:
             if report.when == "call":  # ignore setup/teardown
                 reporter = self._opentestcase(report)
                 reporter.append_pass(report)
         elif report.failed:
+            if report.when == "teardown":
+                # The following vars are needed when xdist plugin is used
+                report_wid = getattr(report, "worker_id", None)
+                report_ii = getattr(report, "item_index", None)
+                close_report = next(
+                    (rep for rep in self.open_reports
+                     if (rep.nodeid == report.nodeid and
+                         getattr(rep, "item_index", None) == report_ii and
+                         getattr(rep, "worker_id", None) == report_wid
+                         )
+                     ), None)
+                if close_report:
+                    # We need to open new testcase in case we have failure in
+                    # call and error in teardown in order to follow junit
+                    # schema
+                    self.finalize(close_report)
+                    self.cnt_double_fail_tests += 1
             reporter = self._opentestcase(report)
             if report.when == "call":
                 reporter.append_failure(report)
+                self.open_reports.append(report)
             else:
                 reporter.append_error(report)
         elif report.skipped:
@@ -345,7 +371,20 @@ class LogXML(object):
             reporter.append_skipped(report)
         self.update_testcase_duration(report)
         if report.when == "teardown":
+            reporter = self._opentestcase(report)
+            reporter.write_captured_output(report)
             self.finalize(report)
+            report_wid = getattr(report, "worker_id", None)
+            report_ii = getattr(report, "item_index", None)
+            close_report = next(
+                (rep for rep in self.open_reports
+                 if (rep.nodeid == report.nodeid and
+                     getattr(rep, "item_index", None) == report_ii and
+                     getattr(rep, "worker_id", None) == report_wid
+                     )
+                 ), None)
+            if close_report:
+                self.open_reports.remove(close_report)
 
     def update_testcase_duration(self, report):
         """accumulates total duration for nodeid from given report and updates
@@ -378,14 +417,15 @@ class LogXML(object):
         suite_stop_time = time.time()
         suite_time_delta = suite_stop_time - self.suite_start_time
 
-        numtests = self.stats['passed'] + self.stats['failure'] + self.stats['skipped'] + self.stats['error']
-
+        numtests = (self.stats['passed'] + self.stats['failure'] +
+                    self.stats['skipped'] + self.stats['error'] -
+                    self.cnt_double_fail_tests)
         logfile.write('<?xml version="1.0" encoding="utf-8"?>')
 
         logfile.write(Junit.testsuite(
             self._get_global_properties_node(),
             [x.to_xml() for x in self.node_reporters_ordered],
-            name="pytest",
+            name=self.suite_name,
             errors=self.stats['error'],
             failures=self.stats['failure'],
             skips=self.stats['skipped'],
@@ -405,9 +445,9 @@ class LogXML(object):
         """
         if self.global_properties:
             return Junit.properties(
-                    [
-                        Junit.property(name=name, value=value)
-                        for name, value in self.global_properties
-                    ]
+                [
+                    Junit.property(name=name, value=value)
+                    for name, value in self.global_properties
+                ]
             )
         return ''
diff --git a/lib/spack/external/_pytest/main.py b/lib/spack/external/_pytest/main.py
index 52876c12a4..eacae8dab1 100644
--- a/lib/spack/external/_pytest/main.py
+++ b/lib/spack/external/_pytest/main.py
@@ -1,18 +1,21 @@
 """ core implementation of testing process: init, session, runtest loop. """
+from __future__ import absolute_import, division, print_function
+
 import functools
 import os
 import sys
 
 import _pytest
+from _pytest import nodes
 import _pytest._code
 import py
-import pytest
 try:
     from collections import MutableMapping as MappingMixin
 except ImportError:
     from UserDict import DictMixin as MappingMixin
 
-from _pytest.config import directory_arg
+from _pytest.config import directory_arg, UsageError, hookimpl
+from _pytest.outcomes import exit
 from _pytest.runner import collect_one_node
 
 tracebackcutdir = py.path.local(_pytest.__file__).dirpath()
@@ -25,63 +28,73 @@ EXIT_INTERNALERROR = 3
 EXIT_USAGEERROR = 4
 EXIT_NOTESTSCOLLECTED = 5
 
+
 def pytest_addoption(parser):
     parser.addini("norecursedirs", "directory patterns to avoid for recursion",
-        type="args", default=['.*', 'build', 'dist', 'CVS', '_darcs', '{arch}', '*.egg'])
-    parser.addini("testpaths", "directories to search for tests when no files or directories are given in the command line.",
-        type="args", default=[])
-    #parser.addini("dirpatterns",
+                  type="args", default=['.*', 'build', 'dist', 'CVS', '_darcs', '{arch}', '*.egg', 'venv'])
+    parser.addini("testpaths", "directories to search for tests when no files or directories are given in the "
+                               "command line.",
+                  type="args", default=[])
+    # parser.addini("dirpatterns",
     #    "patterns specifying possible locations of test files",
     #    type="linelist", default=["**/test_*.txt",
     #            "**/test_*.py", "**/*_test.py"]
-    #)
+    # )
     group = parser.getgroup("general", "running and selection options")
     group._addoption('-x', '--exitfirst', action="store_const",
-               dest="maxfail", const=1,
-               help="exit instantly on first error or failed test."),
+                     dest="maxfail", const=1,
+                     help="exit instantly on first error or failed test."),
     group._addoption('--maxfail', metavar="num",
-               action="store", type=int, dest="maxfail", default=0,
-               help="exit after first num failures or errors.")
+                     action="store", type=int, dest="maxfail", default=0,
+                     help="exit after first num failures or errors.")
     group._addoption('--strict', action="store_true",
-               help="run pytest in strict mode, warnings become errors.")
+                     help="marks not registered in configuration file raise errors.")
     group._addoption("-c", metavar="file", type=str, dest="inifilename",
-               help="load configuration from `file` instead of trying to locate one of the implicit configuration files.")
+                     help="load configuration from `file` instead of trying to locate one of the implicit "
+                          "configuration files.")
     group._addoption("--continue-on-collection-errors", action="store_true",
-               default=False, dest="continue_on_collection_errors",
-               help="Force test execution even if collection errors occur.")
+                     default=False, dest="continue_on_collection_errors",
+                     help="Force test execution even if collection errors occur.")
 
     group = parser.getgroup("collect", "collection")
     group.addoption('--collectonly', '--collect-only', action="store_true",
-        help="only collect tests, don't execute them."),
+                    help="only collect tests, don't execute them."),
     group.addoption('--pyargs', action="store_true",
-        help="try to interpret all arguments as python packages.")
+                    help="try to interpret all arguments as python packages.")
     group.addoption("--ignore", action="append", metavar="path",
-        help="ignore path during collection (multi-allowed).")
+                    help="ignore path during collection (multi-allowed).")
     # when changing this to --conf-cut-dir, config.py Conftest.setinitial
     # needs upgrading as well
     group.addoption('--confcutdir', dest="confcutdir", default=None,
-        metavar="dir", type=functools.partial(directory_arg, optname="--confcutdir"),
-        help="only load conftest.py's relative to specified dir.")
+                    metavar="dir", type=functools.partial(directory_arg, optname="--confcutdir"),
+                    help="only load conftest.py's relative to specified dir.")
     group.addoption('--noconftest', action="store_true",
-        dest="noconftest", default=False,
-        help="Don't load any conftest.py files.")
+                    dest="noconftest", default=False,
+                    help="Don't load any conftest.py files.")
     group.addoption('--keepduplicates', '--keep-duplicates', action="store_true",
-        dest="keepduplicates", default=False,
-        help="Keep duplicate tests.")
+                    dest="keepduplicates", default=False,
+                    help="Keep duplicate tests.")
+    group.addoption('--collect-in-virtualenv', action='store_true',
+                    dest='collect_in_virtualenv', default=False,
+                    help="Don't ignore tests in a local virtualenv directory")
 
     group = parser.getgroup("debugconfig",
-        "test session debugging and configuration")
+                            "test session debugging and configuration")
     group.addoption('--basetemp', dest="basetemp", default=None, metavar="dir",
-               help="base temporary directory for this test run.")
+                    help="base temporary directory for this test run.")
 
 
 def pytest_namespace():
-    collect = dict(Item=Item, Collector=Collector, File=File, Session=Session)
-    return dict(collect=collect)
+    """keeping this one works around a deeper startup issue in pytest
+
+    i tried to find it for a while but the amount of time turned unsustainable,
+    so i put a hack in to revisit later
+    """
+    return {}
 
 
 def pytest_configure(config):
-    pytest.config = config # compatibiltiy
+    __import__('pytest').config = config  # compatibiltiy
 
 
 def wrap_session(config, doit):
@@ -96,17 +109,16 @@ def wrap_session(config, doit):
             config.hook.pytest_sessionstart(session=session)
             initstate = 2
             session.exitstatus = doit(config, session) or 0
-        except pytest.UsageError:
+        except UsageError:
             raise
         except KeyboardInterrupt:
             excinfo = _pytest._code.ExceptionInfo()
-            if initstate < 2 and isinstance(
-                    excinfo.value, pytest.exit.Exception):
+            if initstate < 2 and isinstance(excinfo.value, exit.Exception):
                 sys.stderr.write('{0}: {1}\n'.format(
                     excinfo.typename, excinfo.value.msg))
             config.hook.pytest_keyboard_interrupt(excinfo=excinfo)
             session.exitstatus = EXIT_INTERRUPTED
-        except:
+        except:  # noqa
             excinfo = _pytest._code.ExceptionInfo()
             config.notify_exception(excinfo, config.option)
             session.exitstatus = EXIT_INTERNALERROR
@@ -123,9 +135,11 @@ def wrap_session(config, doit):
         config._ensure_unconfigure()
     return session.exitstatus
 
+
 def pytest_cmdline_main(config):
     return wrap_session(config, _main)
 
+
 def _main(config, session):
     """ default command line protocol for initialization, session,
     running tests and reporting. """
@@ -137,9 +151,11 @@ def _main(config, session):
     elif session.testscollected == 0:
         return EXIT_NOTESTSCOLLECTED
 
+
 def pytest_collection(session):
     return session.perform_collect()
 
+
 def pytest_runtestloop(session):
     if (session.testsfailed and
             not session.config.option.continue_on_collection_errors):
@@ -150,21 +166,36 @@ def pytest_runtestloop(session):
         return True
 
     for i, item in enumerate(session.items):
-        nextitem = session.items[i+1] if i+1 < len(session.items) else None
+        nextitem = session.items[i + 1] if i + 1 < len(session.items) else None
         item.config.hook.pytest_runtest_protocol(item=item, nextitem=nextitem)
         if session.shouldstop:
             raise session.Interrupted(session.shouldstop)
     return True
 
+
+def _in_venv(path):
+    """Attempts to detect if ``path`` is the root of a Virtual Environment by
+    checking for the existence of the appropriate activate script"""
+    bindir = path.join('Scripts' if sys.platform.startswith('win') else 'bin')
+    if not bindir.exists():
+        return False
+    activates = ('activate', 'activate.csh', 'activate.fish',
+                 'Activate', 'Activate.bat', 'Activate.ps1')
+    return any([fname.basename in activates for fname in bindir.listdir()])
+
+
 def pytest_ignore_collect(path, config):
-    p = path.dirpath()
-    ignore_paths = config._getconftest_pathlist("collect_ignore", path=p)
+    ignore_paths = config._getconftest_pathlist("collect_ignore", path=path.dirpath())
     ignore_paths = ignore_paths or []
     excludeopt = config.getoption("ignore")
     if excludeopt:
         ignore_paths.extend([py.path.local(x) for x in excludeopt])
 
-    if path in ignore_paths:
+    if py.path.local(path) in ignore_paths:
+        return True
+
+    allow_in_venv = config.getoption("collect_in_virtualenv")
+    if _in_venv(path) and not allow_in_venv:
         return True
 
     # Skip duplicate paths.
@@ -190,14 +221,22 @@ class FSHookProxy:
         self.__dict__[name] = x
         return x
 
-def compatproperty(name):
-    def fget(self):
-        import warnings
-        warnings.warn("This usage is deprecated, please use pytest.{0} instead".format(name),
-                      PendingDeprecationWarning, stacklevel=2)
-        return getattr(pytest, name)
 
-    return property(fget)
+class _CompatProperty(object):
+    def __init__(self, name):
+        self.name = name
+
+    def __get__(self, obj, owner):
+        if obj is None:
+            return self
+
+        # TODO: reenable in the features branch
+        # warnings.warn(
+        #     "usage of {owner!r}.{name} is deprecated, please use pytest.{name} instead".format(
+        #         name=self.name, owner=type(owner).__name__),
+        #     PendingDeprecationWarning, stacklevel=2)
+        return getattr(__import__('pytest'), self.name)
+
 
 class NodeKeywords(MappingMixin):
     def __init__(self, node):
@@ -269,24 +308,28 @@ class Node(object):
         """ fspath sensitive hook proxy used to call pytest hooks"""
         return self.session.gethookproxy(self.fspath)
 
-    Module = compatproperty("Module")
-    Class = compatproperty("Class")
-    Instance = compatproperty("Instance")
-    Function = compatproperty("Function")
-    File = compatproperty("File")
-    Item = compatproperty("Item")
+    Module = _CompatProperty("Module")
+    Class = _CompatProperty("Class")
+    Instance = _CompatProperty("Instance")
+    Function = _CompatProperty("Function")
+    File = _CompatProperty("File")
+    Item = _CompatProperty("Item")
 
     def _getcustomclass(self, name):
-        cls = getattr(self, name)
-        if cls != getattr(pytest, name):
-            py.log._apiwarn("2.0", "use of node.%s is deprecated, "
-                "use pytest_pycollect_makeitem(...) to create custom "
-                "collection nodes" % name)
+        maybe_compatprop = getattr(type(self), name)
+        if isinstance(maybe_compatprop, _CompatProperty):
+            return getattr(__import__('pytest'), name)
+        else:
+            cls = getattr(self, name)
+            # TODO: reenable in the features branch
+            # warnings.warn("use of node.%s is deprecated, "
+            #    "use pytest_pycollect_makeitem(...) to create custom "
+            #    "collection nodes" % name, category=DeprecationWarning)
         return cls
 
     def __repr__(self):
-        return "<%s %r>" %(self.__class__.__name__,
-                           getattr(self, 'name', None))
+        return "<%s %r>" % (self.__class__.__name__,
+                            getattr(self, 'name', None))
 
     def warn(self, code, message):
         """ generate a warning with the given code and message for this
@@ -295,9 +338,6 @@ class Node(object):
         fslocation = getattr(self, "location", None)
         if fslocation is None:
             fslocation = getattr(self, "fspath", None)
-        else:
-            fslocation = "%s:%s" % (fslocation[0], fslocation[1] + 1)
-
         self.ihook.pytest_logwarning.call_historic(kwargs=dict(
             code=code, message=message,
             nodeid=self.nodeid, fslocation=fslocation))
@@ -335,7 +375,7 @@ class Node(object):
             res = function()
         except py.builtin._sysex:
             raise
-        except:
+        except:  # noqa
             failure = sys.exc_info()
             setattr(self, exattrname, failure)
             raise
@@ -358,9 +398,9 @@ class Node(object):
 
         ``marker`` can be a string or pytest.mark.* instance.
         """
-        from _pytest.mark import MarkDecorator
+        from _pytest.mark import MarkDecorator, MARK_GEN
         if isinstance(marker, py.builtin._basestring):
-            marker = MarkDecorator(marker)
+            marker = getattr(MARK_GEN, marker)
         elif not isinstance(marker, MarkDecorator):
             raise ValueError("is not a string or pytest.mark.* Marker")
         self.keywords[marker.name] = marker
@@ -410,7 +450,7 @@ class Node(object):
             return excinfo.value.formatrepr()
         tbfilter = True
         if self.config.option.fulltrace:
-            style="long"
+            style = "long"
         else:
             tb = _pytest._code.Traceback([excinfo.traceback[-1]])
             self._prunetraceback(excinfo)
@@ -438,6 +478,7 @@ class Node(object):
 
     repr_failure = _repr_failure_py
 
+
 class Collector(Node):
     """ Collector instances create children through collect()
         and thus iteratively build a tree.
@@ -459,10 +500,6 @@ class Collector(Node):
             return str(exc.args[0])
         return self._repr_failure_py(excinfo, style="short")
 
-    def _memocollect(self):
-        """ internal helper method to cache results of calling collect(). """
-        return self._memoizedcall('_collected', lambda: list(self.collect()))
-
     def _prunetraceback(self, excinfo):
         if hasattr(self, 'fspath'):
             traceback = excinfo.traceback
@@ -471,27 +508,38 @@ class Collector(Node):
                 ntraceback = ntraceback.cut(excludepath=tracebackcutdir)
             excinfo.traceback = ntraceback.filter()
 
+
 class FSCollector(Collector):
     def __init__(self, fspath, parent=None, config=None, session=None):
-        fspath = py.path.local(fspath) # xxx only for test_resultlog.py?
+        fspath = py.path.local(fspath)  # xxx only for test_resultlog.py?
         name = fspath.basename
         if parent is not None:
             rel = fspath.relto(parent.fspath)
             if rel:
                 name = rel
-            name = name.replace(os.sep, "/")
+            name = name.replace(os.sep, nodes.SEP)
         super(FSCollector, self).__init__(name, parent, config, session)
         self.fspath = fspath
 
+    def _check_initialpaths_for_relpath(self):
+        for initialpath in self.session._initialpaths:
+            if self.fspath.common(initialpath) == initialpath:
+                return self.fspath.relto(initialpath.dirname)
+
     def _makeid(self):
         relpath = self.fspath.relto(self.config.rootdir)
-        if os.sep != "/":
-            relpath = relpath.replace(os.sep, "/")
+
+        if not relpath:
+            relpath = self._check_initialpaths_for_relpath()
+        if os.sep != nodes.SEP:
+            relpath = relpath.replace(os.sep, nodes.SEP)
         return relpath
 
+
 class File(FSCollector):
     """ base class for collecting tests from a file. """
 
+
 class Item(Node):
     """ a basic test invocation item. Note that for a single function
     there might be multiple test invocation items.
@@ -503,6 +551,21 @@ class Item(Node):
         self._report_sections = []
 
     def add_report_section(self, when, key, content):
+        """
+        Adds a new report section, similar to what's done internally to add stdout and
+        stderr captured output::
+
+            item.add_report_section("call", "stdout", "report section contents")
+
+        :param str when:
+            One of the possible capture states, ``"setup"``, ``"call"``, ``"teardown"``.
+        :param str key:
+            Name of the section, can be customized at will. Pytest uses ``"stdout"`` and
+            ``"stderr"`` internally.
+
+        :param str content:
+            The full contents as a string.
+        """
         if content:
             self._report_sections.append((when, key, content))
 
@@ -526,12 +589,15 @@ class Item(Node):
             self._location = location
             return location
 
+
 class NoMatch(Exception):
     """ raised if matching cannot locate a matching names. """
 
+
 class Interrupted(KeyboardInterrupt):
     """ signals an interrupted test run. """
-    __module__ = 'builtins' # for py3
+    __module__ = 'builtins'  # for py3
+
 
 class Session(FSCollector):
     Interrupted = Interrupted
@@ -550,12 +616,12 @@ class Session(FSCollector):
     def _makeid(self):
         return ""
 
-    @pytest.hookimpl(tryfirst=True)
+    @hookimpl(tryfirst=True)
     def pytest_collectstart(self):
         if self.shouldstop:
             raise self.Interrupted(self.shouldstop)
 
-    @pytest.hookimpl(tryfirst=True)
+    @hookimpl(tryfirst=True)
     def pytest_runtest_logreport(self, report):
         if report.failed and not hasattr(report, 'wasxfail'):
             self.testsfailed += 1
@@ -586,8 +652,9 @@ class Session(FSCollector):
         hook = self.config.hook
         try:
             items = self._perform_collect(args, genitems)
+            self.config.pluginmanager.check_pending()
             hook.pytest_collection_modifyitems(session=self,
-                config=self.config, items=items)
+                                               config=self.config, items=items)
         finally:
             hook.pytest_collection_finish(session=self)
         self.testscollected = len(items)
@@ -614,8 +681,8 @@ class Session(FSCollector):
             for arg, exc in self._notfound:
                 line = "(no name %r in any of %r)" % (arg, exc.args[0])
                 errors.append("not found: %s\n%s" % (arg, line))
-                #XXX: test this
-            raise pytest.UsageError(*errors)
+                # XXX: test this
+            raise UsageError(*errors)
         if not genitems:
             return rep.result
         else:
@@ -643,7 +710,7 @@ class Session(FSCollector):
         names = self._parsearg(arg)
         path = names.pop(0)
         if path.check(dir=1):
-            assert not names, "invalid arg %r" %(arg,)
+            assert not names, "invalid arg %r" % (arg,)
             for path in path.visit(fil=lambda x: x.check(file=1),
                                    rec=self._recurse, bf=True, sort=True):
                 for x in self._collectfile(path):
@@ -702,9 +769,11 @@ class Session(FSCollector):
         path = self.config.invocation_dir.join(relpath, abs=True)
         if not path.check():
             if self.config.option.pyargs:
-                raise pytest.UsageError("file or package not found: " + arg + " (missing __init__.py?)")
+                raise UsageError(
+                    "file or package not found: " + arg +
+                    " (missing __init__.py?)")
             else:
-                raise pytest.UsageError("file not found: " + arg)
+                raise UsageError("file not found: " + arg)
         parts[0] = path
         return parts
 
@@ -727,11 +796,11 @@ class Session(FSCollector):
         nextnames = names[1:]
         resultnodes = []
         for node in matching:
-            if isinstance(node, pytest.Item):
+            if isinstance(node, Item):
                 if not names:
                     resultnodes.append(node)
                 continue
-            assert isinstance(node, pytest.Collector)
+            assert isinstance(node, Collector)
             rep = collect_one_node(node)
             if rep.passed:
                 has_matched = False
@@ -744,16 +813,20 @@ class Session(FSCollector):
                 if not has_matched and len(rep.result) == 1 and x.name == "()":
                     nextnames.insert(0, name)
                     resultnodes.extend(self.matchnodes([x], nextnames))
-            node.ihook.pytest_collectreport(report=rep)
+            else:
+                # report collection failures here to avoid failing to run some test
+                # specified in the command line because the module could not be
+                # imported (#134)
+                node.ihook.pytest_collectreport(report=rep)
         return resultnodes
 
     def genitems(self, node):
         self.trace("genitems", node)
-        if isinstance(node, pytest.Item):
+        if isinstance(node, Item):
             node.ihook.pytest_itemcollected(item=node)
             yield node
         else:
-            assert isinstance(node, pytest.Collector)
+            assert isinstance(node, Collector)
             rep = collect_one_node(node)
             if rep.passed:
                 for subnode in rep.result:
diff --git a/lib/spack/external/_pytest/mark.py b/lib/spack/external/_pytest/mark.py
index 357a60492e..454722ca2c 100644
--- a/lib/spack/external/_pytest/mark.py
+++ b/lib/spack/external/_pytest/mark.py
@@ -1,5 +1,75 @@
 """ generic mechanism for marking and selecting python functions. """
+from __future__ import absolute_import, division, print_function
+
 import inspect
+import warnings
+from collections import namedtuple
+from operator import attrgetter
+from .compat import imap
+from .deprecated import MARK_PARAMETERSET_UNPACKING
+
+
+def alias(name, warning=None):
+    getter = attrgetter(name)
+
+    def warned(self):
+        warnings.warn(warning, stacklevel=2)
+        return getter(self)
+
+    return property(getter if warning is None else warned, doc='alias for ' + name)
+
+
+class ParameterSet(namedtuple('ParameterSet', 'values, marks, id')):
+    @classmethod
+    def param(cls, *values, **kw):
+        marks = kw.pop('marks', ())
+        if isinstance(marks, MarkDecorator):
+            marks = marks,
+        else:
+            assert isinstance(marks, (tuple, list, set))
+
+        def param_extract_id(id=None):
+            return id
+
+        id = param_extract_id(**kw)
+        return cls(values, marks, id)
+
+    @classmethod
+    def extract_from(cls, parameterset, legacy_force_tuple=False):
+        """
+        :param parameterset:
+            a legacy style parameterset that may or may not be a tuple,
+            and may or may not be wrapped into a mess of mark objects
+
+        :param legacy_force_tuple:
+            enforce tuple wrapping so single argument tuple values
+            don't get decomposed and break tests
+
+        """
+
+        if isinstance(parameterset, cls):
+            return parameterset
+        if not isinstance(parameterset, MarkDecorator) and legacy_force_tuple:
+            return cls.param(parameterset)
+
+        newmarks = []
+        argval = parameterset
+        while isinstance(argval, MarkDecorator):
+            newmarks.append(MarkDecorator(Mark(
+                argval.markname, argval.args[:-1], argval.kwargs)))
+            argval = argval.args[-1]
+        assert not isinstance(argval, ParameterSet)
+        if legacy_force_tuple:
+            argval = argval,
+
+        if newmarks:
+            warnings.warn(MARK_PARAMETERSET_UNPACKING)
+
+        return cls(argval, marks=newmarks, id=None)
+
+    @property
+    def deprecated_arg_dict(self):
+        return dict((mark.name, mark) for mark in self.marks)
 
 
 class MarkerError(Exception):
@@ -7,8 +77,8 @@ class MarkerError(Exception):
     """Error in use of a pytest marker/attribute."""
 
 
-def pytest_namespace():
-    return {'mark': MarkGenerator()}
+def param(*values, **kw):
+    return ParameterSet.param(*values, **kw)
 
 
 def pytest_addoption(parser):
@@ -21,7 +91,8 @@ def pytest_addoption(parser):
              "where all names are substring-matched against test names "
              "and their parent classes. Example: -k 'test_method or test_"
              "other' matches all test functions and classes whose name "
-             "contains 'test_method' or 'test_other'. "
+             "contains 'test_method' or 'test_other', while -k 'not test_method' "
+             "matches those that don't contain 'test_method' in their names. "
              "Additionally keywords are matched to classes and functions "
              "containing extra names in their 'extra_keyword_matches' set, "
              "as well as functions which have names assigned directly to them."
@@ -66,7 +137,7 @@ def pytest_collection_modifyitems(items, config):
         return
     # pytest used to allow "-" for negating
     # but today we just allow "-" at the beginning, use "not" instead
-    # we probably remove "-" alltogether soon
+    # we probably remove "-" altogether soon
     if keywordexpr.startswith("-"):
         keywordexpr = "not " + keywordexpr[1:]
     selectuntil = False
@@ -96,6 +167,7 @@ def pytest_collection_modifyitems(items, config):
 class MarkMapping:
     """Provides a local mapping for markers where item access
     resolves to True if the marker is present. """
+
     def __init__(self, keywords):
         mymarks = set()
         for key, value in keywords.items():
@@ -111,6 +183,7 @@ class KeywordMapping:
     """Provides a local mapping for keywords.
     Given a list of names, map any substring of one of these names to True.
     """
+
     def __init__(self, names):
         self._names = names
 
@@ -162,9 +235,13 @@ def matchkeyword(colitem, keywordexpr):
 
 
 def pytest_configure(config):
-    import pytest
+    config._old_mark_config = MARK_GEN._config
     if config.option.strict:
-        pytest.mark._config = config
+        MARK_GEN._config = config
+
+
+def pytest_unconfigure(config):
+    MARK_GEN._config = getattr(config, '_old_mark_config', None)
 
 
 class MarkGenerator:
@@ -178,13 +255,14 @@ class MarkGenerator:
 
     will set a 'slowtest' :class:`MarkInfo` object
     on the ``test_function`` object. """
+    _config = None
 
     def __getattr__(self, name):
         if name[0] == "_":
             raise AttributeError("Marker name must NOT start with underscore")
-        if hasattr(self, '_config'):
+        if self._config is not None:
             self._check(name)
-        return MarkDecorator(name)
+        return MarkDecorator(Mark(name, (), {}))
 
     def _check(self, name):
         try:
@@ -192,18 +270,21 @@ class MarkGenerator:
                 return
         except AttributeError:
             pass
-        self._markers = l = set()
+        self._markers = values = set()
         for line in self._config.getini("markers"):
-            beginning = line.split(":", 1)
-            x = beginning[0].split("(", 1)[0]
-            l.add(x)
+            marker, _ = line.split(":", 1)
+            marker = marker.rstrip()
+            x = marker.split("(", 1)[0]
+            values.add(x)
         if name not in self._markers:
             raise AttributeError("%r not a registered marker" % (name,))
 
+
 def istestfunc(func):
     return hasattr(func, "__call__") and \
         getattr(func, "__name__", "<lambda>") != "<lambda>"
 
+
 class MarkDecorator:
     """ A decorator for test functions and test classes.  When applied
     it will create :class:`MarkInfo` objects which may be
@@ -237,19 +318,35 @@ class MarkDecorator:
     additional keyword or positional arguments.
 
     """
-    def __init__(self, name, args=None, kwargs=None):
-        self.name = name
-        self.args = args or ()
-        self.kwargs = kwargs or {}
+
+    def __init__(self, mark):
+        assert isinstance(mark, Mark), repr(mark)
+        self.mark = mark
+
+    name = alias('mark.name')
+    args = alias('mark.args')
+    kwargs = alias('mark.kwargs')
 
     @property
     def markname(self):
-        return self.name # for backward-compat (2.4.1 had this attr)
+        return self.name  # for backward-compat (2.4.1 had this attr)
+
+    def __eq__(self, other):
+        return self.mark == other.mark if isinstance(other, MarkDecorator) else False
 
     def __repr__(self):
-        d = self.__dict__.copy()
-        name = d.pop('name')
-        return "<MarkDecorator %r %r>" % (name, d)
+        return "<MarkDecorator %r>" % (self.mark,)
+
+    def with_args(self, *args, **kwargs):
+        """ return a MarkDecorator with extra arguments added
+
+        unlike call this can be used even if the sole argument is a callable/class
+
+        :return: MarkDecorator
+        """
+
+        mark = Mark(self.name, args, kwargs)
+        return self.__class__(self.mark.combined_with(mark))
 
     def __call__(self, *args, **kwargs):
         """ if passed a single callable argument: decorate it with mark info.
@@ -259,70 +356,110 @@ class MarkDecorator:
             is_class = inspect.isclass(func)
             if len(args) == 1 and (istestfunc(func) or is_class):
                 if is_class:
-                    if hasattr(func, 'pytestmark'):
-                        mark_list = func.pytestmark
-                        if not isinstance(mark_list, list):
-                            mark_list = [mark_list]
-                        # always work on a copy to avoid updating pytestmark
-                        # from a superclass by accident
-                        mark_list = mark_list + [self]
-                        func.pytestmark = mark_list
-                    else:
-                        func.pytestmark = [self]
+                    store_mark(func, self.mark)
                 else:
-                    holder = getattr(func, self.name, None)
-                    if holder is None:
-                        holder = MarkInfo(
-                            self.name, self.args, self.kwargs
-                        )
-                        setattr(func, self.name, holder)
-                    else:
-                        holder.add(self.args, self.kwargs)
+                    store_legacy_markinfo(func, self.mark)
+                    store_mark(func, self.mark)
                 return func
-        kw = self.kwargs.copy()
-        kw.update(kwargs)
-        args = self.args + args
-        return self.__class__(self.name, args=args, kwargs=kw)
-
-
-def extract_argvalue(maybe_marked_args):
-    # TODO: incorrect mark data, the old code wanst able to collect lists
-    # individual parametrized argument sets can be wrapped in a series
-    # of markers in which case we unwrap the values and apply the mark
-    # at Function init
-    newmarks = {}
-    argval = maybe_marked_args
-    while isinstance(argval, MarkDecorator):
-        newmark = MarkDecorator(argval.markname,
-                                argval.args[:-1], argval.kwargs)
-        newmarks[newmark.markname] = newmark
-        argval = argval.args[-1]
-    return argval, newmarks
-
-
-class MarkInfo:
+        return self.with_args(*args, **kwargs)
+
+
+def get_unpacked_marks(obj):
+    """
+    obtain the unpacked marks that are stored on a object
+    """
+    mark_list = getattr(obj, 'pytestmark', [])
+
+    if not isinstance(mark_list, list):
+        mark_list = [mark_list]
+    return [
+        getattr(mark, 'mark', mark)  # unpack MarkDecorator
+        for mark in mark_list
+    ]
+
+
+def store_mark(obj, mark):
+    """store a Mark on a object
+    this is used to implement the Mark declarations/decorators correctly
+    """
+    assert isinstance(mark, Mark), mark
+    # always reassign name to avoid updating pytestmark
+    # in a reference that was only borrowed
+    obj.pytestmark = get_unpacked_marks(obj) + [mark]
+
+
+def store_legacy_markinfo(func, mark):
+    """create the legacy MarkInfo objects and put them onto the function
+    """
+    if not isinstance(mark, Mark):
+        raise TypeError("got {mark!r} instead of a Mark".format(mark=mark))
+    holder = getattr(func, mark.name, None)
+    if holder is None:
+        holder = MarkInfo(mark)
+        setattr(func, mark.name, holder)
+    else:
+        holder.add_mark(mark)
+
+
+class Mark(namedtuple('Mark', 'name, args, kwargs')):
+
+    def combined_with(self, other):
+        assert self.name == other.name
+        return Mark(
+            self.name, self.args + other.args,
+            dict(self.kwargs, **other.kwargs))
+
+
+class MarkInfo(object):
     """ Marking object created by :class:`MarkDecorator` instances. """
-    def __init__(self, name, args, kwargs):
-        #: name of attribute
-        self.name = name
-        #: positional argument list, empty if none specified
-        self.args = args
-        #: keyword argument dictionary, empty if nothing specified
-        self.kwargs = kwargs.copy()
-        self._arglist = [(args, kwargs.copy())]
+
+    def __init__(self, mark):
+        assert isinstance(mark, Mark), repr(mark)
+        self.combined = mark
+        self._marks = [mark]
+
+    name = alias('combined.name')
+    args = alias('combined.args')
+    kwargs = alias('combined.kwargs')
 
     def __repr__(self):
-        return "<MarkInfo %r args=%r kwargs=%r>" % (
-            self.name, self.args, self.kwargs
-        )
+        return "<MarkInfo {0!r}>".format(self.combined)
 
-    def add(self, args, kwargs):
+    def add_mark(self, mark):
         """ add a MarkInfo with the given args and kwargs. """
-        self._arglist.append((args, kwargs))
-        self.args += args
-        self.kwargs.update(kwargs)
+        self._marks.append(mark)
+        self.combined = self.combined.combined_with(mark)
 
     def __iter__(self):
         """ yield MarkInfo objects each relating to a marking-call. """
-        for args, kwargs in self._arglist:
-            yield MarkInfo(self.name, args, kwargs)
+        return imap(MarkInfo, self._marks)
+
+
+MARK_GEN = MarkGenerator()
+
+
+def _marked(func, mark):
+    """ Returns True if :func: is already marked with :mark:, False otherwise.
+    This can happen if marker is applied to class and the test file is
+    invoked more than once.
+    """
+    try:
+        func_mark = getattr(func, mark.name)
+    except AttributeError:
+        return False
+    return mark.args == func_mark.args and mark.kwargs == func_mark.kwargs
+
+
+def transfer_markers(funcobj, cls, mod):
+    """
+    this function transfers class level markers and module level markers
+    into function level markinfo objects
+
+    this is the main reason why marks are so broken
+    the resolution will involve phasing out function level MarkInfo objects
+
+    """
+    for obj in (cls, mod):
+        for mark in get_unpacked_marks(obj):
+            if not _marked(funcobj, mark):
+                store_legacy_markinfo(funcobj, mark)
diff --git a/lib/spack/external/_pytest/monkeypatch.py b/lib/spack/external/_pytest/monkeypatch.py
index 852e72beda..39ac770135 100644
--- a/lib/spack/external/_pytest/monkeypatch.py
+++ b/lib/spack/external/_pytest/monkeypatch.py
@@ -1,17 +1,18 @@
 """ monkeypatching and mocking functionality.  """
+from __future__ import absolute_import, division, print_function
 
-import os, sys
+import os
+import sys
 import re
 
 from py.builtin import _basestring
-
-import pytest
+from _pytest.fixtures import fixture
 
 RE_IMPORT_ERROR_NAME = re.compile("^No module named (.*)$")
 
 
-@pytest.fixture
-def monkeypatch(request):
+@fixture
+def monkeypatch():
     """The returned ``monkeypatch`` fixture provides these
     helper methods to modify objects, dictionaries or os.environ::
 
@@ -30,8 +31,8 @@ def monkeypatch(request):
     will be raised if the set/deletion operation has no target.
     """
     mpatch = MonkeyPatch()
-    request.addfinalizer(mpatch.undo)
-    return mpatch
+    yield mpatch
+    mpatch.undo()
 
 
 def resolve(name):
@@ -70,9 +71,9 @@ def annotated_getattr(obj, name, ann):
         obj = getattr(obj, name)
     except AttributeError:
         raise AttributeError(
-                '%r object at %s has no attribute %r' % (
-                    type(obj).__name__, ann, name
-                )
+            '%r object at %s has no attribute %r' % (
+                type(obj).__name__, ann, name
+            )
         )
     return obj
 
diff --git a/lib/spack/external/_pytest/nodes.py b/lib/spack/external/_pytest/nodes.py
new file mode 100644
index 0000000000..ad3af2ce67
--- /dev/null
+++ b/lib/spack/external/_pytest/nodes.py
@@ -0,0 +1,37 @@
+SEP = "/"
+
+
+def _splitnode(nodeid):
+    """Split a nodeid into constituent 'parts'.
+
+    Node IDs are strings, and can be things like:
+        ''
+        'testing/code'
+        'testing/code/test_excinfo.py'
+        'testing/code/test_excinfo.py::TestFormattedExcinfo::()'
+
+    Return values are lists e.g.
+        []
+        ['testing', 'code']
+        ['testing', 'code', 'test_excinfo.py']
+        ['testing', 'code', 'test_excinfo.py', 'TestFormattedExcinfo', '()']
+    """
+    if nodeid == '':
+        # If there is no root node at all, return an empty list so the caller's logic can remain sane
+        return []
+    parts = nodeid.split(SEP)
+    # Replace single last element 'test_foo.py::Bar::()' with multiple elements 'test_foo.py', 'Bar', '()'
+    parts[-1:] = parts[-1].split("::")
+    return parts
+
+
+def ischildnode(baseid, nodeid):
+    """Return True if the nodeid is a child node of the baseid.
+
+    E.g. 'foo/bar::Baz::()' is a child of 'foo', 'foo/bar' and 'foo/bar::Baz', but not of 'foo/blorp'
+    """
+    base_parts = _splitnode(baseid)
+    node_parts = _splitnode(nodeid)
+    if len(node_parts) < len(base_parts):
+        return False
+    return node_parts[:len(base_parts)] == base_parts
diff --git a/lib/spack/external/_pytest/nose.py b/lib/spack/external/_pytest/nose.py
index 0387468686..d246c5603d 100644
--- a/lib/spack/external/_pytest/nose.py
+++ b/lib/spack/external/_pytest/nose.py
@@ -1,10 +1,11 @@
 """ run test suites written for nose. """
+from __future__ import absolute_import, division, print_function
 
 import sys
 
 import py
-import pytest
-from _pytest import unittest
+from _pytest import unittest, runner, python
+from _pytest.config import hookimpl
 
 
 def get_skip_exceptions():
@@ -19,45 +20,46 @@ def get_skip_exceptions():
 def pytest_runtest_makereport(item, call):
     if call.excinfo and call.excinfo.errisinstance(get_skip_exceptions()):
         # let's substitute the excinfo with a pytest.skip one
-        call2 = call.__class__(lambda:
-                    pytest.skip(str(call.excinfo.value)), call.when)
+        call2 = call.__class__(
+            lambda: runner.skip(str(call.excinfo.value)), call.when)
         call.excinfo = call2.excinfo
 
 
-@pytest.hookimpl(trylast=True)
+@hookimpl(trylast=True)
 def pytest_runtest_setup(item):
     if is_potential_nosetest(item):
-        if isinstance(item.parent, pytest.Generator):
+        if isinstance(item.parent, python.Generator):
             gen = item.parent
             if not hasattr(gen, '_nosegensetup'):
                 call_optional(gen.obj, 'setup')
-                if isinstance(gen.parent, pytest.Instance):
+                if isinstance(gen.parent, python.Instance):
                     call_optional(gen.parent.obj, 'setup')
                 gen._nosegensetup = True
         if not call_optional(item.obj, 'setup'):
             # call module level setup if there is no object level one
             call_optional(item.parent.obj, 'setup')
-        #XXX this implies we only call teardown when setup worked
+        # XXX this implies we only call teardown when setup worked
         item.session._setupstate.addfinalizer((lambda: teardown_nose(item)), item)
 
+
 def teardown_nose(item):
     if is_potential_nosetest(item):
         if not call_optional(item.obj, 'teardown'):
             call_optional(item.parent.obj, 'teardown')
-        #if hasattr(item.parent, '_nosegensetup'):
+        # if hasattr(item.parent, '_nosegensetup'):
         #    #call_optional(item._nosegensetup, 'teardown')
         #    del item.parent._nosegensetup
 
 
 def pytest_make_collect_report(collector):
-    if isinstance(collector, pytest.Generator):
+    if isinstance(collector, python.Generator):
         call_optional(collector.obj, 'setup')
 
 
 def is_potential_nosetest(item):
     # extra check needed since we do not do nose style setup/teardown
     # on direct unittest style classes
-    return isinstance(item, pytest.Function) and \
+    return isinstance(item, python.Function) and \
         not isinstance(item, unittest.TestCaseFunction)
 
 
diff --git a/lib/spack/external/_pytest/outcomes.py b/lib/spack/external/_pytest/outcomes.py
new file mode 100644
index 0000000000..ff5ef756d9
--- /dev/null
+++ b/lib/spack/external/_pytest/outcomes.py
@@ -0,0 +1,140 @@
+"""
+exception classes and constants handling test outcomes
+as well as functions creating them
+"""
+from __future__ import absolute_import, division, print_function
+import py
+import sys
+
+
+class OutcomeException(BaseException):
+    """ OutcomeException and its subclass instances indicate and
+        contain info about test and collection outcomes.
+    """
+    def __init__(self, msg=None, pytrace=True):
+        BaseException.__init__(self, msg)
+        self.msg = msg
+        self.pytrace = pytrace
+
+    def __repr__(self):
+        if self.msg:
+            val = self.msg
+            if isinstance(val, bytes):
+                val = py._builtin._totext(val, errors='replace')
+            return val
+        return "<%s instance>" % (self.__class__.__name__,)
+    __str__ = __repr__
+
+
+TEST_OUTCOME = (OutcomeException, Exception)
+
+
+class Skipped(OutcomeException):
+    # XXX hackish: on 3k we fake to live in the builtins
+    # in order to have Skipped exception printing shorter/nicer
+    __module__ = 'builtins'
+
+    def __init__(self, msg=None, pytrace=True, allow_module_level=False):
+        OutcomeException.__init__(self, msg=msg, pytrace=pytrace)
+        self.allow_module_level = allow_module_level
+
+
+class Failed(OutcomeException):
+    """ raised from an explicit call to pytest.fail() """
+    __module__ = 'builtins'
+
+
+class Exit(KeyboardInterrupt):
+    """ raised for immediate program exits (no tracebacks/summaries)"""
+    def __init__(self, msg="unknown reason"):
+        self.msg = msg
+        KeyboardInterrupt.__init__(self, msg)
+
+# exposed helper methods
+
+
+def exit(msg):
+    """ exit testing process as if KeyboardInterrupt was triggered. """
+    __tracebackhide__ = True
+    raise Exit(msg)
+
+
+exit.Exception = Exit
+
+
+def skip(msg=""):
+    """ skip an executing test with the given message.  Note: it's usually
+    better to use the pytest.mark.skipif marker to declare a test to be
+    skipped under certain conditions like mismatching platforms or
+    dependencies.  See the pytest_skipping plugin for details.
+    """
+    __tracebackhide__ = True
+    raise Skipped(msg=msg)
+
+
+skip.Exception = Skipped
+
+
+def fail(msg="", pytrace=True):
+    """ explicitly fail an currently-executing test with the given Message.
+
+    :arg pytrace: if false the msg represents the full failure information
+                  and no python traceback will be reported.
+    """
+    __tracebackhide__ = True
+    raise Failed(msg=msg, pytrace=pytrace)
+
+
+fail.Exception = Failed
+
+
+class XFailed(fail.Exception):
+    """ raised from an explicit call to pytest.xfail() """
+
+
+def xfail(reason=""):
+    """ xfail an executing test or setup functions with the given reason."""
+    __tracebackhide__ = True
+    raise XFailed(reason)
+
+
+xfail.Exception = XFailed
+
+
+def importorskip(modname, minversion=None):
+    """ return imported module if it has at least "minversion" as its
+    __version__ attribute.  If no minversion is specified the a skip
+    is only triggered if the module can not be imported.
+    """
+    import warnings
+    __tracebackhide__ = True
+    compile(modname, '', 'eval')  # to catch syntaxerrors
+    should_skip = False
+
+    with warnings.catch_warnings():
+        # make sure to ignore ImportWarnings that might happen because
+        # of existing directories with the same name we're trying to
+        # import but without a __init__.py file
+        warnings.simplefilter('ignore')
+        try:
+            __import__(modname)
+        except ImportError:
+            # Do not raise chained exception here(#1485)
+            should_skip = True
+    if should_skip:
+        raise Skipped("could not import %r" % (modname,), allow_module_level=True)
+    mod = sys.modules[modname]
+    if minversion is None:
+        return mod
+    verattr = getattr(mod, '__version__', None)
+    if minversion is not None:
+        try:
+            from pkg_resources import parse_version as pv
+        except ImportError:
+            raise Skipped("we have a required version for %r but can not import "
+                          "pkg_resources to parse version strings." % (modname,),
+                          allow_module_level=True)
+        if verattr is None or pv(verattr) < pv(minversion):
+            raise Skipped("module %r has __version__ %r, required is: %r" % (
+                          modname, verattr, minversion), allow_module_level=True)
+    return mod
diff --git a/lib/spack/external/_pytest/pastebin.py b/lib/spack/external/_pytest/pastebin.py
index 9f1cf90637..9d689819f0 100644
--- a/lib/spack/external/_pytest/pastebin.py
+++ b/lib/spack/external/_pytest/pastebin.py
@@ -1,4 +1,6 @@
 """ submit failure or test session information to a pastebin service. """
+from __future__ import absolute_import, division, print_function
+
 import pytest
 import sys
 import tempfile
@@ -7,9 +9,9 @@ import tempfile
 def pytest_addoption(parser):
     group = parser.getgroup("terminal reporting")
     group._addoption('--pastebin', metavar="mode",
-        action='store', dest="pastebin", default=None,
-        choices=['failed', 'all'],
-        help="send failed|all info to bpaste.net pastebin service.")
+                     action='store', dest="pastebin", default=None,
+                     choices=['failed', 'all'],
+                     help="send failed|all info to bpaste.net pastebin service.")
 
 
 @pytest.hookimpl(trylast=True)
@@ -95,4 +97,4 @@ def pytest_terminal_summary(terminalreporter):
             s = tw.stringio.getvalue()
             assert len(s)
             pastebinurl = create_new_paste(s)
-            tr.write_line("%s --> %s" %(msg, pastebinurl))
+            tr.write_line("%s --> %s" % (msg, pastebinurl))
diff --git a/lib/spack/external/_pytest/pytester.py b/lib/spack/external/_pytest/pytester.py
index d87c0a762a..2db85dff22 100644
--- a/lib/spack/external/_pytest/pytester.py
+++ b/lib/spack/external/_pytest/pytester.py
@@ -1,4 +1,6 @@
 """ (disabled by default) support for testing pytest and pytest plugins. """
+from __future__ import absolute_import, division, print_function
+
 import codecs
 import gc
 import os
@@ -10,8 +12,9 @@ import time
 import traceback
 from fnmatch import fnmatch
 
-from py.builtin import print_
+from weakref import WeakKeyDictionary
 
+from _pytest.capture import MultiCapture, SysCapture
 from _pytest._code import Source
 import py
 import pytest
@@ -22,13 +25,13 @@ from _pytest.assertion.rewrite import AssertionRewritingHook
 def pytest_addoption(parser):
     # group = parser.getgroup("pytester", "pytester (self-tests) options")
     parser.addoption('--lsof',
-           action="store_true", dest="lsof", default=False,
-           help=("run FD checks if lsof is available"))
+                     action="store_true", dest="lsof", default=False,
+                     help=("run FD checks if lsof is available"))
 
     parser.addoption('--runpytest', default="inprocess", dest="runpytest",
-           choices=("inprocess", "subprocess", ),
-           help=("run pytest sub runs in tests using an 'inprocess' "
-                 "or 'subprocess' (python -m main) method"))
+                     choices=("inprocess", "subprocess", ),
+                     help=("run pytest sub runs in tests using an 'inprocess' "
+                           "or 'subprocess' (python -m main) method"))
 
 
 def pytest_configure(config):
@@ -59,7 +62,7 @@ class LsofFdLeakChecker(object):
     def _parse_lsof_output(self, out):
         def isopen(line):
             return line.startswith('f') and ("deleted" not in line and
-                'mem' not in line and "txt" not in line and 'cwd' not in line)
+                                             'mem' not in line and "txt" not in line and 'cwd' not in line)
 
         open_files = []
 
@@ -85,7 +88,7 @@ class LsofFdLeakChecker(object):
             return True
 
     @pytest.hookimpl(hookwrapper=True, tryfirst=True)
-    def pytest_runtest_item(self, item):
+    def pytest_runtest_protocol(self, item):
         lines1 = self.get_open_files()
         yield
         if hasattr(sys, "pypy_version_info"):
@@ -104,7 +107,8 @@ class LsofFdLeakChecker(object):
             error.extend([str(f) for f in lines2])
             error.append(error[0])
             error.append("*** function %s:%s: %s " % item.location)
-            pytest.fail("\n".join(error), pytrace=False)
+            error.append("See issue #2366")
+            item.warn('', "\n".join(error))
 
 
 # XXX copied from execnet's conftest.py - needs to be merged
@@ -118,6 +122,7 @@ winpymap = {
     'python3.5': r'C:\Python35\python.exe',
 }
 
+
 def getexecutable(name, cache={}):
     try:
         return cache[name]
@@ -126,19 +131,20 @@ def getexecutable(name, cache={}):
         if executable:
             import subprocess
             popen = subprocess.Popen([str(executable), "--version"],
-                universal_newlines=True, stderr=subprocess.PIPE)
+                                     universal_newlines=True, stderr=subprocess.PIPE)
             out, err = popen.communicate()
             if name == "jython":
                 if not err or "2.5" not in err:
                     executable = None
                 if "2.5.2" in err:
-                    executable = None # http://bugs.jython.org/issue1790
+                    executable = None  # http://bugs.jython.org/issue1790
             elif popen.returncode != 0:
                 # Handle pyenv's 127.
                 executable = None
         cache[name] = executable
         return executable
 
+
 @pytest.fixture(params=['python2.6', 'python2.7', 'python3.3', "python3.4",
                         'pypy', 'pypy3'])
 def anypython(request):
@@ -155,6 +161,8 @@ def anypython(request):
     return executable
 
 # used at least by pytest-xdist plugin
+
+
 @pytest.fixture
 def _pytest(request):
     """ Return a helper which offers a gethookrecorder(hook)
@@ -163,6 +171,7 @@ def _pytest(request):
     """
     return PytestArg(request)
 
+
 class PytestArg:
     def __init__(self, request):
         self.request = request
@@ -173,9 +182,9 @@ class PytestArg:
         return hookrecorder
 
 
-def get_public_names(l):
-    """Only return names from iterator l without a leading underscore."""
-    return [x for x in l if x[0] != "_"]
+def get_public_names(values):
+    """Only return names from iterator values without a leading underscore."""
+    return [x for x in values if x[0] != "_"]
 
 
 class ParsedCall:
@@ -186,7 +195,7 @@ class ParsedCall:
     def __repr__(self):
         d = self.__dict__.copy()
         del d['_name']
-        return "<ParsedCall %r(**%r)>" %(self._name, d)
+        return "<ParsedCall %r(**%r)>" % (self._name, d)
 
 
 class HookRecorder:
@@ -226,15 +235,15 @@ class HookRecorder:
             name, check = entries.pop(0)
             for ind, call in enumerate(self.calls[i:]):
                 if call._name == name:
-                    print_("NAMEMATCH", name, call)
+                    print("NAMEMATCH", name, call)
                     if eval(check, backlocals, call.__dict__):
-                        print_("CHECKERMATCH", repr(check), "->", call)
+                        print("CHECKERMATCH", repr(check), "->", call)
                     else:
-                        print_("NOCHECKERMATCH", repr(check), "-", call)
+                        print("NOCHECKERMATCH", repr(check), "-", call)
                         continue
                     i += ind + 1
                     break
-                print_("NONAMEMATCH", name, "with", call)
+                print("NONAMEMATCH", name, "with", call)
             else:
                 pytest.fail("could not find %r check %r" % (name, check))
 
@@ -249,9 +258,9 @@ class HookRecorder:
         pytest.fail("\n".join(lines))
 
     def getcall(self, name):
-        l = self.getcalls(name)
-        assert len(l) == 1, (name, l)
-        return l[0]
+        values = self.getcalls(name)
+        assert len(values) == 1, (name, values)
+        return values[0]
 
     # functionality for test reports
 
@@ -260,9 +269,9 @@ class HookRecorder:
         return [x.report for x in self.getcalls(names)]
 
     def matchreport(self, inamepart="",
-        names="pytest_runtest_logreport pytest_collectreport", when=None):
+                    names="pytest_runtest_logreport pytest_collectreport", when=None):
         """ return a testreport whose dotted import path matches """
-        l = []
+        values = []
         for rep in self.getreports(names=names):
             try:
                 if not when and rep.when != "call" and rep.passed:
@@ -273,14 +282,14 @@ class HookRecorder:
             if when and getattr(rep, 'when', None) != when:
                 continue
             if not inamepart or inamepart in rep.nodeid.split("::"):
-                l.append(rep)
-        if not l:
+                values.append(rep)
+        if not values:
             raise ValueError("could not find test report matching %r: "
                              "no test reports at all!" % (inamepart,))
-        if len(l) > 1:
+        if len(values) > 1:
             raise ValueError(
-                "found 2 or more testreports matching %r: %s" %(inamepart, l))
-        return l[0]
+                "found 2 or more testreports matching %r: %s" % (inamepart, values))
+        return values[0]
 
     def getfailures(self,
                     names='pytest_runtest_logreport pytest_collectreport'):
@@ -294,7 +303,7 @@ class HookRecorder:
         skipped = []
         failed = []
         for rep in self.getreports(
-            "pytest_collectreport pytest_runtest_logreport"):
+                "pytest_collectreport pytest_runtest_logreport"):
             if rep.passed:
                 if getattr(rep, "when", None) == "call":
                     passed.append(rep)
@@ -332,7 +341,9 @@ def testdir(request, tmpdir_factory):
     return Testdir(request, tmpdir_factory)
 
 
-rex_outcome = re.compile("(\d+) ([\w-]+)")
+rex_outcome = re.compile(r"(\d+) ([\w-]+)")
+
+
 class RunResult:
     """The result of running a command.
 
@@ -348,6 +359,7 @@ class RunResult:
     :duration: Duration in seconds.
 
     """
+
     def __init__(self, ret, outlines, errlines, duration):
         self.ret = ret
         self.outlines = outlines
@@ -367,15 +379,19 @@ class RunResult:
                     for num, cat in outcomes:
                         d[cat] = int(num)
                     return d
+        raise ValueError("Pytest terminal report not found")
 
-    def assert_outcomes(self, passed=0, skipped=0, failed=0):
+    def assert_outcomes(self, passed=0, skipped=0, failed=0, error=0):
         """ assert that the specified outcomes appear with the respective
         numbers (0 means it didn't occur) in the text output from a test run."""
         d = self.parseoutcomes()
-        assert passed == d.get("passed", 0)
-        assert skipped == d.get("skipped", 0)
-        assert failed == d.get("failed", 0)
-
+        obtained = {
+            'passed': d.get('passed', 0),
+            'skipped': d.get('skipped', 0),
+            'failed': d.get('failed', 0),
+            'error': d.get('error', 0),
+        }
+        assert obtained == dict(passed=passed, skipped=skipped, failed=failed, error=error)
 
 
 class Testdir:
@@ -401,6 +417,7 @@ class Testdir:
 
     def __init__(self, request, tmpdir_factory):
         self.request = request
+        self._mod_collections = WeakKeyDictionary()
         # XXX remove duplication with tmpdir plugin
         basetmp = tmpdir_factory.ensuretemp("testdir")
         name = request.function.__name__
@@ -414,7 +431,7 @@ class Testdir:
         self.plugins = []
         self._savesyspath = (list(sys.path), list(sys.meta_path))
         self._savemodulekeys = set(sys.modules)
-        self.chdir() # always chdir
+        self.chdir()  # always chdir
         self.request.addfinalizer(self.finalize)
         method = self.request.config.getoption("--runpytest")
         if method == "inprocess":
@@ -446,9 +463,10 @@ class Testdir:
         the module is re-imported.
         """
         for name in set(sys.modules).difference(self._savemodulekeys):
-            # it seems zope.interfaces is keeping some state
-            # (used by twisted related tests)
-            if name != "zope.interface":
+            # some zope modules used by twisted-related tests keeps internal
+            # state and can't be deleted; we had some trouble in the past
+            # with zope.interface for example
+            if not name.startswith("zope"):
                 del sys.modules[name]
 
     def make_hook_recorder(self, pluginmanager):
@@ -468,7 +486,7 @@ class Testdir:
         if not hasattr(self, '_olddir'):
             self._olddir = old
 
-    def _makefile(self, ext, args, kwargs):
+    def _makefile(self, ext, args, kwargs, encoding="utf-8"):
         items = list(kwargs.items())
         if args:
             source = py.builtin._totext("\n").join(
@@ -488,8 +506,8 @@ class Testdir:
 
             source_unicode = "\n".join([my_totext(line) for line in source.lines])
             source = py.builtin._totext(source_unicode)
-            content = source.strip().encode("utf-8") # + "\n"
-            #content = content.rstrip() + "\n"
+            content = source.strip().encode(encoding)  # + "\n"
+            # content = content.rstrip() + "\n"
             p.write(content, "wb")
             if ret is None:
                 ret = p
@@ -565,7 +583,7 @@ class Testdir:
     def mkpydir(self, name):
         """Create a new python package.
 
-        This creates a (sub)direcotry with an empty ``__init__.py``
+        This creates a (sub)directory with an empty ``__init__.py``
         file so that is recognised as a python package.
 
         """
@@ -574,6 +592,7 @@ class Testdir:
         return p
 
     Session = Session
+
     def getnode(self, config, arg):
         """Return the collection node of a file.
 
@@ -654,13 +673,13 @@ class Testdir:
 
         """
         p = self.makepyfile(source)
-        l = list(cmdlineargs) + [p]
-        return self.inline_run(*l)
+        values = list(cmdlineargs) + [p]
+        return self.inline_run(*values)
 
     def inline_genitems(self, *args):
         """Run ``pytest.main(['--collectonly'])`` in-process.
 
-        Retuns a tuple of the collected items and a
+        Returns a tuple of the collected items and a
         :py:class:`HookRecorder` instance.
 
         This runs the :py:func:`pytest.main` function to run all of
@@ -733,7 +752,8 @@ class Testdir:
         if kwargs.get("syspathinsert"):
             self.syspathinsert()
         now = time.time()
-        capture = py.io.StdCapture()
+        capture = MultiCapture(Capture=SysCapture)
+        capture.start_capturing()
         try:
             try:
                 reprec = self.inline_run(*args, **kwargs)
@@ -748,13 +768,14 @@ class Testdir:
                 class reprec:
                     ret = 3
         finally:
-            out, err = capture.reset()
+            out, err = capture.readouterr()
+            capture.stop_capturing()
             sys.stdout.write(out)
             sys.stderr.write(err)
 
         res = RunResult(reprec.ret,
                         out.split("\n"), err.split("\n"),
-                        time.time()-now)
+                        time.time() - now)
         res.reprec = reprec
         return res
 
@@ -770,11 +791,11 @@ class Testdir:
         args = [str(x) for x in args]
         for x in args:
             if str(x).startswith('--basetemp'):
-                #print ("basedtemp exists: %s" %(args,))
+                # print("basedtemp exists: %s" %(args,))
                 break
         else:
             args.append("--basetemp=%s" % self.tmpdir.dirpath('basetemp'))
-            #print ("added basetemp: %s" %(args,))
+            # print("added basetemp: %s" %(args,))
         return args
 
     def parseconfig(self, *args):
@@ -812,7 +833,7 @@ class Testdir:
         self.request.addfinalizer(config._ensure_unconfigure)
         return config
 
-    def getitem(self,  source, funcname="test_func"):
+    def getitem(self, source, funcname="test_func"):
         """Return the test item for a test function.
 
         This writes the source to a python file and runs pytest's
@@ -829,10 +850,10 @@ class Testdir:
         for item in items:
             if item.name == funcname:
                 return item
-        assert 0, "%r item not found in module:\n%s\nitems: %s" %(
+        assert 0, "%r item not found in module:\n%s\nitems: %s" % (
                   funcname, source, items)
 
-    def getitems(self,  source):
+    def getitems(self, source):
         """Return all test items collected from the module.
 
         This writes the source to a python file and runs pytest's
@@ -843,7 +864,7 @@ class Testdir:
         modcol = self.getmodulecol(source)
         return self.genitems([modcol])
 
-    def getmodulecol(self,  source, configargs=(), withinit=False):
+    def getmodulecol(self, source, configargs=(), withinit=False):
         """Return the module collection node for ``source``.
 
         This writes ``source`` to a file using :py:meth:`makepyfile`
@@ -856,15 +877,16 @@ class Testdir:
            :py:meth:`parseconfigure`.
 
         :param withinit: Whether to also write a ``__init__.py`` file
-           to the temporarly directory to ensure it is a package.
+           to the temporary directory to ensure it is a package.
 
         """
         kw = {self.request.function.__name__: Source(source).strip()}
         path = self.makepyfile(**kw)
         if withinit:
-            self.makepyfile(__init__ = "#")
+            self.makepyfile(__init__="#")
         self.config = config = self.parseconfigure(path, *configargs)
         node = self.getnode(config, path)
+
         return node
 
     def collect_by_name(self, modcol, name):
@@ -879,7 +901,9 @@ class Testdir:
         :param name: The name of the node to return.
 
         """
-        for colitem in modcol._memocollect():
+        if modcol not in self._mod_collections:
+            self._mod_collections[modcol] = list(modcol.collect())
+        for colitem in self._mod_collections[modcol]:
             if colitem.name == name:
                 return colitem
 
@@ -896,8 +920,11 @@ class Testdir:
         env['PYTHONPATH'] = os.pathsep.join(filter(None, [
             str(os.getcwd()), env.get('PYTHONPATH', '')]))
         kw['env'] = env
-        return subprocess.Popen(cmdargs,
-                                stdout=stdout, stderr=stderr, **kw)
+
+        popen = subprocess.Popen(cmdargs, stdin=subprocess.PIPE, stdout=stdout, stderr=stderr, **kw)
+        popen.stdin.close()
+
+        return popen
 
     def run(self, *cmdargs):
         """Run a command with arguments.
@@ -914,14 +941,14 @@ class Testdir:
         cmdargs = [str(x) for x in cmdargs]
         p1 = self.tmpdir.join("stdout")
         p2 = self.tmpdir.join("stderr")
-        print_("running:", ' '.join(cmdargs))
-        print_("     in:", str(py.path.local()))
+        print("running:", ' '.join(cmdargs))
+        print("     in:", str(py.path.local()))
         f1 = codecs.open(str(p1), "w", encoding="utf8")
         f2 = codecs.open(str(p2), "w", encoding="utf8")
         try:
             now = time.time()
             popen = self.popen(cmdargs, stdout=f1, stderr=f2,
-                close_fds=(sys.platform != "win32"))
+                               close_fds=(sys.platform != "win32"))
             ret = popen.wait()
         finally:
             f1.close()
@@ -936,19 +963,19 @@ class Testdir:
             f2.close()
         self._dump_lines(out, sys.stdout)
         self._dump_lines(err, sys.stderr)
-        return RunResult(ret, out, err, time.time()-now)
+        return RunResult(ret, out, err, time.time() - now)
 
     def _dump_lines(self, lines, fp):
         try:
             for line in lines:
-                py.builtin.print_(line, file=fp)
+                print(line, file=fp)
         except UnicodeEncodeError:
             print("couldn't print to %s because of encoding" % (fp,))
 
     def _getpytestargs(self):
         # we cannot use "(sys.executable,script)"
         # because on windows the script is e.g. a pytest.exe
-        return (sys.executable, _pytest_fullpath,) # noqa
+        return (sys.executable, _pytest_fullpath,)  # noqa
 
     def runpython(self, script):
         """Run a python script using sys.executable as interpreter.
@@ -975,12 +1002,12 @@ class Testdir:
 
         """
         p = py.path.local.make_numbered_dir(prefix="runpytest-",
-            keep=None, rootdir=self.tmpdir)
+                                            keep=None, rootdir=self.tmpdir)
         args = ('--basetemp=%s' % p, ) + args
-        #for x in args:
+        # for x in args:
         #    if '--confcutdir' in str(x):
         #        break
-        #else:
+        # else:
         #    pass
         #    args = ('--confcutdir=.',) + args
         plugins = [x for x in self.plugins if isinstance(x, str)]
@@ -998,7 +1025,7 @@ class Testdir:
         The pexpect child is returned.
 
         """
-        basetemp = self.tmpdir.mkdir("pexpect")
+        basetemp = self.tmpdir.mkdir("temp-pexpect")
         invoke = " ".join(map(str, self._getpytestargs()))
         cmd = "%s --basetemp=%s %s" % (invoke, basetemp, string)
         return self.spawn(cmd, expect_timeout=expect_timeout)
@@ -1019,12 +1046,13 @@ class Testdir:
         child.timeout = expect_timeout
         return child
 
+
 def getdecoded(out):
-        try:
-            return out.decode("utf-8")
-        except UnicodeDecodeError:
-            return "INTERNAL not-utf8-decodeable, truncated string:\n%s" % (
-                    py.io.saferepr(out),)
+    try:
+        return out.decode("utf-8")
+    except UnicodeDecodeError:
+        return "INTERNAL not-utf8-decodeable, truncated string:\n%s" % (
+            py.io.saferepr(out),)
 
 
 class LineComp:
@@ -1054,7 +1082,7 @@ class LineMatcher:
 
     """
 
-    def __init__(self,  lines):
+    def __init__(self, lines):
         self.lines = lines
         self._log_output = []
 
@@ -1093,7 +1121,7 @@ class LineMatcher:
         """
         for i, line in enumerate(self.lines):
             if fnline == line or fnmatch(line, fnline):
-                return self.lines[i+1:]
+                return self.lines[i + 1:]
         raise ValueError("line %r not found in output" % fnline)
 
     def _log(self, *args):
diff --git a/lib/spack/external/_pytest/python.py b/lib/spack/external/_pytest/python.py
index 53815da2f0..41fd2bdb7f 100644
--- a/lib/spack/external/_pytest/python.py
+++ b/lib/spack/external/_pytest/python.py
@@ -1,26 +1,30 @@
 """ Python test discovery, setup and run of test functions. """
+from __future__ import absolute_import, division, print_function
 
 import fnmatch
 import inspect
 import sys
+import os
 import collections
-import math
+from textwrap import dedent
 from itertools import count
 
 import py
-import pytest
 from _pytest.mark import MarkerError
-
+from _pytest.config import hookimpl
 
 import _pytest
 import _pytest._pluggy as pluggy
 from _pytest import fixtures
+from _pytest import main
 from _pytest.compat import (
-    isclass, isfunction, is_generator, _escape_strings,
+    isclass, isfunction, is_generator, _ascii_escaped,
     REGEX_TYPE, STRING_TYPES, NoneType, NOTSET,
     get_real_func, getfslineno, safe_getattr,
-    getlocation, enum,
+    safe_str, getlocation, enum,
 )
+from _pytest.outcomes import fail
+from _pytest.mark import transfer_markers
 
 cutdir1 = py.path.local(pluggy.__file__.rstrip("oc"))
 cutdir2 = py.path.local(_pytest.__file__).dirpath()
@@ -45,10 +49,9 @@ def filter_traceback(entry):
     return p != cutdir1 and not p.relto(cutdir2) and not p.relto(cutdir3)
 
 
-
 def pyobj_property(name):
     def get(self):
-        node = self.getparent(getattr(pytest, name))
+        node = self.getparent(getattr(__import__('pytest'), name))
         if node is not None:
             return node.obj
     doc = "python %s object this node was collected from (can be None)." % (
@@ -59,8 +62,8 @@ def pyobj_property(name):
 def pytest_addoption(parser):
     group = parser.getgroup("general")
     group.addoption('--fixtures', '--funcargs',
-               action="store_true", dest="showfixtures", default=False,
-               help="show available fixtures, sorted by plugin appearance")
+                    action="store_true", dest="showfixtures", default=False,
+                    help="show available fixtures, sorted by plugin appearance")
     group.addoption(
         '--fixtures-per-test',
         action="store_true",
@@ -69,20 +72,20 @@ def pytest_addoption(parser):
         help="show fixtures per test",
     )
     parser.addini("usefixtures", type="args", default=[],
-        help="list of default fixtures to be used with this project")
+                  help="list of default fixtures to be used with this project")
     parser.addini("python_files", type="args",
-        default=['test_*.py', '*_test.py'],
-        help="glob-style file patterns for Python test module discovery")
-    parser.addini("python_classes", type="args", default=["Test",],
-        help="prefixes or glob names for Python test class discovery")
-    parser.addini("python_functions", type="args", default=["test",],
-        help="prefixes or glob names for Python test function and "
-             "method discovery")
+                  default=['test_*.py', '*_test.py'],
+                  help="glob-style file patterns for Python test module discovery")
+    parser.addini("python_classes", type="args", default=["Test", ],
+                  help="prefixes or glob names for Python test class discovery")
+    parser.addini("python_functions", type="args", default=["test", ],
+                  help="prefixes or glob names for Python test function and "
+                  "method discovery")
 
     group.addoption("--import-mode", default="prepend",
-        choices=["prepend", "append"], dest="importmode",
-        help="prepend/append to sys.path when importing test modules, "
-             "default is to prepend.")
+                    choices=["prepend", "append"], dest="importmode",
+                    help="prepend/append to sys.path when importing test modules, "
+                    "default is to prepend.")
 
 
 def pytest_cmdline_main(config):
@@ -109,39 +112,25 @@ def pytest_generate_tests(metafunc):
     for marker in markers:
         metafunc.parametrize(*marker.args, **marker.kwargs)
 
+
 def pytest_configure(config):
     config.addinivalue_line("markers",
-        "parametrize(argnames, argvalues): call a test function multiple "
-        "times passing in different arguments in turn. argvalues generally "
-        "needs to be a list of values if argnames specifies only one name "
-        "or a list of tuples of values if argnames specifies multiple names. "
-        "Example: @parametrize('arg1', [1,2]) would lead to two calls of the "
-        "decorated test function, one with arg1=1 and another with arg1=2."
-        "see http://pytest.org/latest/parametrize.html for more info and "
-        "examples."
-    )
+                            "parametrize(argnames, argvalues): call a test function multiple "
+                            "times passing in different arguments in turn. argvalues generally "
+                            "needs to be a list of values if argnames specifies only one name "
+                            "or a list of tuples of values if argnames specifies multiple names. "
+                            "Example: @parametrize('arg1', [1,2]) would lead to two calls of the "
+                            "decorated test function, one with arg1=1 and another with arg1=2."
+                            "see http://pytest.org/latest/parametrize.html for more info and "
+                            "examples."
+                            )
     config.addinivalue_line("markers",
-        "usefixtures(fixturename1, fixturename2, ...): mark tests as needing "
-        "all of the specified fixtures. see http://pytest.org/latest/fixture.html#usefixtures "
-    )
+                            "usefixtures(fixturename1, fixturename2, ...): mark tests as needing "
+                            "all of the specified fixtures. see http://pytest.org/latest/fixture.html#usefixtures "
+                            )
+
 
-@pytest.hookimpl(trylast=True)
-def pytest_namespace():
-    raises.Exception = pytest.fail.Exception
-    return {
-        'raises': raises,
-        'approx': approx,
-        'collect': {
-            'Module': Module,
-            'Class': Class,
-            'Instance': Instance,
-            'Function': Function,
-            'Generator': Generator,
-        }
-    }
-
-
-@pytest.hookimpl(trylast=True)
+@hookimpl(trylast=True)
 def pytest_pyfunc_call(pyfuncitem):
     testfunction = pyfuncitem.obj
     if pyfuncitem._isyieldedfunction():
@@ -154,6 +143,7 @@ def pytest_pyfunc_call(pyfuncitem):
         testfunction(**testargs)
     return True
 
+
 def pytest_collect_file(path, parent):
     ext = path.ext
     if ext == ".py":
@@ -162,19 +152,21 @@ def pytest_collect_file(path, parent):
                 if path.fnmatch(pat):
                     break
             else:
-               return
+                return
         ihook = parent.session.gethookproxy(path)
         return ihook.pytest_pycollect_makemodule(path=path, parent=parent)
 
+
 def pytest_pycollect_makemodule(path, parent):
     return Module(path, parent)
 
-@pytest.hookimpl(hookwrapper=True)
+
+@hookimpl(hookwrapper=True)
 def pytest_pycollect_makeitem(collector, name, obj):
     outcome = yield
     res = outcome.get_result()
     if res is not None:
-        raise StopIteration
+        return
     # nothing was collected elsewhere, let's do it here
     if isclass(obj):
         if collector.istestclass(obj, name):
@@ -187,9 +179,8 @@ def pytest_pycollect_makeitem(collector, name, obj):
         # or a funtools.wrapped.
         # We musn't if it's been wrapped with mock.patch (python 2 only)
         if not (isfunction(obj) or isfunction(get_real_func(obj))):
-            collector.warn(code="C2", message=
-                "cannot collect %r because it is not a function."
-                % name, )
+            collector.warn(code="C2", message="cannot collect %r because it is not a function."
+                           % name, )
         elif getattr(obj, "__test__", True):
             if is_generator(obj):
                 res = Generator(name, parent=collector)
@@ -197,9 +188,9 @@ def pytest_pycollect_makeitem(collector, name, obj):
                 res = list(collector._genfunctions(name, obj))
             outcome.force_result(res)
 
-def pytest_make_parametrize_id(config, val):
-    return None
 
+def pytest_make_parametrize_id(config, val, argname=None):
+    return None
 
 
 class PyobjContext(object):
@@ -207,6 +198,7 @@ class PyobjContext(object):
     cls = pyobj_property("Class")
     instance = pyobj_property("Instance")
 
+
 class PyobjMixin(PyobjContext):
     def obj():
         def fget(self):
@@ -235,8 +227,7 @@ class PyobjMixin(PyobjContext):
                 continue
             name = node.name
             if isinstance(node, Module):
-                assert name.endswith(".py")
-                name = name[:-3]
+                name = os.path.splitext(name)[0]
                 if stopatmodule:
                     if includemodule:
                         parts.append(name)
@@ -265,7 +256,8 @@ class PyobjMixin(PyobjContext):
         assert isinstance(lineno, int)
         return fspath, lineno, modpath
 
-class PyCollector(PyobjMixin, pytest.Collector):
+
+class PyCollector(PyobjMixin, main.Collector):
 
     def funcnamefilter(self, name):
         return self._matches_prefix_or_glob_option('python_functions', name)
@@ -283,10 +275,22 @@ class PyCollector(PyobjMixin, pytest.Collector):
         return self._matches_prefix_or_glob_option('python_classes', name)
 
     def istestfunction(self, obj, name):
-        return (
-            (self.funcnamefilter(name) or self.isnosetest(obj)) and
-            safe_getattr(obj, "__call__", False) and fixtures.getfixturemarker(obj) is None
-        )
+        if self.funcnamefilter(name) or self.isnosetest(obj):
+            if isinstance(obj, staticmethod):
+                # static methods need to be unwrapped
+                obj = safe_getattr(obj, '__func__', False)
+                if obj is False:
+                    # Python 2.6 wraps in a different way that we won't try to handle
+                    msg = "cannot collect static method %r because " \
+                          "it is not a function (always the case in Python 2.6)"
+                    self.warn(
+                        code="C2", message=msg % name)
+                    return False
+            return (
+                safe_getattr(obj, "__call__", False) and fixtures.getfixturemarker(obj) is None
+            )
+        else:
+            return False
 
     def istestclass(self, obj, name):
         return self.classnamefilter(name) or self.isnosetest(obj)
@@ -317,7 +321,7 @@ class PyCollector(PyobjMixin, pytest.Collector):
         for basecls in inspect.getmro(self.obj.__class__):
             dicts.append(basecls.__dict__)
         seen = {}
-        l = []
+        values = []
         for dic in dicts:
             for name, obj in list(dic.items()):
                 if name in seen:
@@ -328,12 +332,12 @@ class PyCollector(PyobjMixin, pytest.Collector):
                     continue
                 if not isinstance(res, list):
                     res = [res]
-                l.extend(res)
-        l.sort(key=lambda item: item.reportinfo()[:2])
-        return l
+                values.extend(res)
+        values.sort(key=lambda item: item.reportinfo()[:2])
+        return values
 
     def makeitem(self, name, obj):
-        #assert self.ihook.fspath == self.fspath, self
+        # assert self.ihook.fspath == self.fspath, self
         return self.ihook.pytest_pycollect_makeitem(
             collector=self, name=name, obj=obj)
 
@@ -369,43 +373,16 @@ class PyCollector(PyobjMixin, pytest.Collector):
                 yield Function(name=subname, parent=self,
                                callspec=callspec, callobj=funcobj,
                                fixtureinfo=fixtureinfo,
-                               keywords={callspec.id:True},
+                               keywords={callspec.id: True},
                                originalname=name,
                                )
 
 
-def _marked(func, mark):
-    """ Returns True if :func: is already marked with :mark:, False otherwise.
-    This can happen if marker is applied to class and the test file is
-    invoked more than once.
-    """
-    try:
-        func_mark = getattr(func, mark.name)
-    except AttributeError:
-        return False
-    return mark.args == func_mark.args and mark.kwargs == func_mark.kwargs
-
-
-def transfer_markers(funcobj, cls, mod):
-    # XXX this should rather be code in the mark plugin or the mark
-    # plugin should merge with the python plugin.
-    for holder in (cls, mod):
-        try:
-            pytestmark = holder.pytestmark
-        except AttributeError:
-            continue
-        if isinstance(pytestmark, list):
-            for mark in pytestmark:
-                if not _marked(funcobj, mark):
-                    mark(funcobj)
-        else:
-            if not _marked(funcobj, pytestmark):
-                pytestmark(funcobj)
-
-class Module(pytest.File, PyCollector):
+class Module(main.File, PyCollector):
     """ Collector for test classes and functions. """
+
     def _getobj(self):
-        return self._memoizedcall('_obj', self._importtestmodule)
+        return self._importtestmodule()
 
     def collect(self):
         self.session._fixturemanager.parsefactories(self)
@@ -429,7 +406,7 @@ class Module(pytest.File, PyCollector):
                 "  %s\n"
                 "HINT: remove __pycache__ / .pyc files and/or use a "
                 "unique basename for your test file modules"
-                 % e.args
+                % e.args
             )
         except ImportError:
             from _pytest._code.code import ExceptionInfo
@@ -437,7 +414,7 @@ class Module(pytest.File, PyCollector):
             if self.config.getoption('verbose') < 2:
                 exc_info.traceback = exc_info.traceback.filter(filter_traceback)
             exc_repr = exc_info.getrepr(style='short') if exc_info.traceback else exc_info.exconly()
-            formatted_tb = py._builtin._totext(exc_repr)
+            formatted_tb = safe_str(exc_repr)
             raise self.CollectError(
                 "ImportError while importing test module '{fspath}'.\n"
                 "Hint: make sure your test modules/packages have valid Python names.\n"
@@ -448,9 +425,10 @@ class Module(pytest.File, PyCollector):
             if e.allow_module_level:
                 raise
             raise self.CollectError(
-                "Using pytest.skip outside of a test is not allowed. If you are "
-                "trying to decorate a test function, use the @pytest.mark.skip "
-                "or @pytest.mark.skipif decorators instead."
+                "Using pytest.skip outside of a test is not allowed. "
+                "To decorate a test function, use the @pytest.mark.skip "
+                "or @pytest.mark.skipif decorators instead, and to skip a "
+                "module use `pytestmark = pytest.mark.{skip,skipif}."
             )
         self.config.pluginmanager.consider_module(mod)
         return mod
@@ -501,10 +479,13 @@ def _get_xunit_func(obj, name):
 
 class Class(PyCollector):
     """ Collector for test methods. """
+
     def collect(self):
+        if not safe_getattr(self.obj, "__test__", True):
+            return []
         if hasinit(self.obj):
             self.warn("C1", "cannot collect test class %r because it has a "
-                "__init__ constructor" % self.obj.__name__)
+                      "__init__ constructor" % self.obj.__name__)
             return []
         elif hasnew(self.obj):
             self.warn("C1", "cannot collect test class %r because it has a "
@@ -525,6 +506,7 @@ class Class(PyCollector):
             fin_class = getattr(fin_class, '__func__', fin_class)
             self.addfinalizer(lambda: fin_class(self.obj))
 
+
 class Instance(PyCollector):
     def _getobj(self):
         return self.parent.obj()
@@ -537,6 +519,7 @@ class Instance(PyCollector):
         self.obj = self._getobj()
         return self.obj
 
+
 class FunctionMixin(PyobjMixin):
     """ mixin for the code common to Function and Generator.
     """
@@ -572,7 +555,7 @@ class FunctionMixin(PyobjMixin):
             if ntraceback == traceback:
                 ntraceback = ntraceback.cut(path=path)
                 if ntraceback == traceback:
-                    #ntraceback = ntraceback.cut(excludepath=cutdir2)
+                    # ntraceback = ntraceback.cut(excludepath=cutdir2)
                     ntraceback = ntraceback.filter(filter_traceback)
                     if not ntraceback:
                         ntraceback = traceback
@@ -586,11 +569,11 @@ class FunctionMixin(PyobjMixin):
                         entry.set_repr_style('short')
 
     def _repr_failure_py(self, excinfo, style="long"):
-        if excinfo.errisinstance(pytest.fail.Exception):
+        if excinfo.errisinstance(fail.Exception):
             if not excinfo.value.pytrace:
                 return py._builtin._totext(excinfo.value)
         return super(FunctionMixin, self)._repr_failure_py(excinfo,
-            style=style)
+                                                           style=style)
 
     def repr_failure(self, excinfo, outerr=None):
         assert outerr is None, "XXX outerr usage is deprecated"
@@ -609,27 +592,27 @@ class Generator(FunctionMixin, PyCollector):
         self.session._setupstate.prepare(self)
         # see FunctionMixin.setup and test_setupstate_is_preserved_134
         self._preservedparent = self.parent.obj
-        l = []
+        values = []
         seen = {}
         for i, x in enumerate(self.obj()):
             name, call, args = self.getcallargs(x)
             if not callable(call):
-                raise TypeError("%r yielded non callable test %r" %(self.obj, call,))
+                raise TypeError("%r yielded non callable test %r" % (self.obj, call,))
             if name is None:
                 name = "[%d]" % i
             else:
                 name = "['%s']" % name
             if name in seen:
-                raise ValueError("%r generated tests with non-unique name %r" %(self, name))
+                raise ValueError("%r generated tests with non-unique name %r" % (self, name))
             seen[name] = True
-            l.append(self.Function(name, self, args=args, callobj=call))
-            self.config.warn('C1', deprecated.YIELD_TESTS, fslocation=self.fspath)
-        return l
+            values.append(self.Function(name, self, args=args, callobj=call))
+        self.warn('C1', deprecated.YIELD_TESTS)
+        return values
 
     def getcallargs(self, obj):
         if not isinstance(obj, (tuple, list)):
             obj = (obj,)
-        # explict naming
+        # explicit naming
         if isinstance(obj[0], py.builtin._basestring):
             name = obj[0]
             obj = obj[1:]
@@ -679,7 +662,7 @@ class CallSpec2(object):
 
     def _checkargnotcontained(self, arg):
         if arg in self.params or arg in self.funcargs:
-            raise ValueError("duplicate %r" %(arg,))
+            raise ValueError("duplicate %r" % (arg,))
 
     def getparam(self, name):
         try:
@@ -695,7 +678,7 @@ class CallSpec2(object):
 
     def setmulti(self, valtypes, argnames, valset, id, keywords, scopenum,
                  param_index):
-        for arg,val in zip(argnames, valset):
+        for arg, val in zip(argnames, valset):
             self._checkargnotcontained(arg)
             valtype_for_arg = valtypes[arg]
             getattr(self, valtype_for_arg)[arg] = val
@@ -724,6 +707,7 @@ class Metafunc(fixtures.FuncargnamesCompatAttr):
     test configuration or values specified in the class or module where a
     test function is defined.
     """
+
     def __init__(self, function, fixtureinfo, config, cls=None, module=None):
         #: access to the :class:`_pytest.config.Config` object for the test session
         self.config = config
@@ -745,7 +729,7 @@ class Metafunc(fixtures.FuncargnamesCompatAttr):
         self._arg2fixturedefs = fixtureinfo.name2fixturedefs
 
     def parametrize(self, argnames, argvalues, indirect=False, ids=None,
-        scope=None):
+                    scope=None):
         """ Add new invocations to the underlying test function using the list
         of argvalues for the given argnames.  Parametrization is performed
         during the collection phase.  If you need to setup expensive resources
@@ -784,36 +768,34 @@ class Metafunc(fixtures.FuncargnamesCompatAttr):
             to set a dynamic scope using test context or configuration.
         """
         from _pytest.fixtures import scope2index
-        from _pytest.mark import extract_argvalue
+        from _pytest.mark import MARK_GEN, ParameterSet
         from py.io import saferepr
 
-        unwrapped_argvalues = []
-        newkeywords = []
-        for maybe_marked_args in argvalues:
-            argval, newmarks = extract_argvalue(maybe_marked_args)
-            unwrapped_argvalues.append(argval)
-            newkeywords.append(newmarks)
-        argvalues = unwrapped_argvalues
-
         if not isinstance(argnames, (tuple, list)):
             argnames = [x.strip() for x in argnames.split(",") if x.strip()]
-            if len(argnames) == 1:
-                argvalues = [(val,) for val in argvalues]
-        if not argvalues:
-            argvalues = [(NOTSET,) * len(argnames)]
-            # we passed a empty list to parameterize, skip that test
-            #
+            force_tuple = len(argnames) == 1
+        else:
+            force_tuple = False
+        parameters = [
+            ParameterSet.extract_from(x, legacy_force_tuple=force_tuple)
+            for x in argvalues]
+        del argvalues
+
+        if not parameters:
             fs, lineno = getfslineno(self.function)
-            newmark = pytest.mark.skip(
-                reason="got empty parameter set %r, function %s at %s:%d" % (
-                    argnames, self.function.__name__, fs, lineno))
-            newkeywords = [{newmark.markname: newmark}]
+            reason = "got empty parameter set %r, function %s at %s:%d" % (
+                argnames, self.function.__name__, fs, lineno)
+            mark = MARK_GEN.skip(reason=reason)
+            parameters.append(ParameterSet(
+                values=(NOTSET,) * len(argnames),
+                marks=[mark],
+                id=None,
+            ))
 
         if scope is None:
             scope = _find_parametrized_scope(argnames, self._arg2fixturedefs, indirect)
 
-        scopenum = scope2index(
-            scope, descr='call to {0}'.format(self.parametrize))
+        scopenum = scope2index(scope, descr='call to {0}'.format(self.parametrize))
         valtypes = {}
         for arg in argnames:
             if arg not in self.fixturenames:
@@ -823,7 +805,7 @@ class Metafunc(fixtures.FuncargnamesCompatAttr):
                     name = 'fixture' if indirect else 'argument'
                 raise ValueError(
                     "%r uses no %s %r" % (
-                            self.function, name, arg))
+                        self.function, name, arg))
 
         if indirect is True:
             valtypes = dict.fromkeys(argnames, "params")
@@ -841,22 +823,26 @@ class Metafunc(fixtures.FuncargnamesCompatAttr):
             idfn = ids
             ids = None
         if ids:
-            if len(ids) != len(argvalues):
-                raise ValueError('%d tests specified with %d ids' %(
-                                 len(argvalues), len(ids)))
+            if len(ids) != len(parameters):
+                raise ValueError('%d tests specified with %d ids' % (
+                                 len(parameters), len(ids)))
             for id_value in ids:
                 if id_value is not None and not isinstance(id_value, py.builtin._basestring):
                     msg = 'ids must be list of strings, found: %s (type: %s)'
                     raise ValueError(msg % (saferepr(id_value), type(id_value).__name__))
-        ids = idmaker(argnames, argvalues, idfn, ids, self.config)
+        ids = idmaker(argnames, parameters, idfn, ids, self.config)
         newcalls = []
         for callspec in self._calls or [CallSpec2(self)]:
-            elements = zip(ids, argvalues, newkeywords, count())
-            for a_id, valset, keywords, param_index in elements:
-                assert len(valset) == len(argnames)
+            elements = zip(ids, parameters, count())
+            for a_id, param, param_index in elements:
+                if len(param.values) != len(argnames):
+                    raise ValueError(
+                        'In "parametrize" the number of values ({0}) must be '
+                        'equal to the number of names ({1})'.format(
+                            param.values, argnames))
                 newcallspec = callspec.copy(self)
-                newcallspec.setmulti(valtypes, argnames, valset, a_id,
-                                     keywords, scopenum, param_index)
+                newcallspec.setmulti(valtypes, argnames, param.values, a_id,
+                                     param.deprecated_arg_dict, scopenum, param_index)
                 newcalls.append(newcallspec)
         self._calls = newcalls
 
@@ -880,7 +866,7 @@ class Metafunc(fixtures.FuncargnamesCompatAttr):
         if funcargs is not None:
             for name in funcargs:
                 if name not in self.fixturenames:
-                    pytest.fail("funcarg %r not used in this function." % name)
+                    fail("funcarg %r not used in this function." % name)
         else:
             funcargs = {}
         if id is None:
@@ -910,7 +896,7 @@ def _find_parametrized_scope(argnames, arg2fixturedefs, indirect):
     from _pytest.fixtures import scopes
     indirect_as_list = isinstance(indirect, (list, tuple))
     all_arguments_are_fixtures = indirect is True or \
-                                 indirect_as_list and len(indirect) == argnames
+        indirect_as_list and len(indirect) == argnames
     if all_arguments_are_fixtures:
         fixturedefs = arg2fixturedefs or {}
         used_scopes = [fixturedef[0].scope for name, fixturedef in fixturedefs.items()]
@@ -925,41 +911,51 @@ def _find_parametrized_scope(argnames, arg2fixturedefs, indirect):
 
 def _idval(val, argname, idx, idfn, config=None):
     if idfn:
+        s = None
         try:
             s = idfn(val)
-            if s:
-                return _escape_strings(s)
         except Exception:
-            pass
+            # See issue https://github.com/pytest-dev/pytest/issues/2169
+            import warnings
+            msg = "Raised while trying to determine id of parameter %s at position %d." % (argname, idx)
+            msg += '\nUpdate your code as this will raise an error in pytest-4.0.'
+            warnings.warn(msg, DeprecationWarning)
+        if s:
+            return _ascii_escaped(s)
 
     if config:
-        hook_id = config.hook.pytest_make_parametrize_id(config=config, val=val)
+        hook_id = config.hook.pytest_make_parametrize_id(
+            config=config, val=val, argname=argname)
         if hook_id:
             return hook_id
 
     if isinstance(val, STRING_TYPES):
-        return _escape_strings(val)
+        return _ascii_escaped(val)
     elif isinstance(val, (float, int, bool, NoneType)):
         return str(val)
     elif isinstance(val, REGEX_TYPE):
-        return _escape_strings(val.pattern)
+        return _ascii_escaped(val.pattern)
     elif enum is not None and isinstance(val, enum.Enum):
         return str(val)
     elif isclass(val) and hasattr(val, '__name__'):
         return val.__name__
-    return str(argname)+str(idx)
+    return str(argname) + str(idx)
 
-def _idvalset(idx, valset, argnames, idfn, ids, config=None):
+
+def _idvalset(idx, parameterset, argnames, idfn, ids, config=None):
+    if parameterset.id is not None:
+        return parameterset.id
     if ids is None or (idx >= len(ids) or ids[idx] is None):
         this_id = [_idval(val, argname, idx, idfn, config)
-                   for val, argname in zip(valset, argnames)]
+                   for val, argname in zip(parameterset.values, argnames)]
         return "-".join(this_id)
     else:
-        return _escape_strings(ids[idx])
+        return _ascii_escaped(ids[idx])
+
 
-def idmaker(argnames, argvalues, idfn=None, ids=None, config=None):
-    ids = [_idvalset(valindex, valset, argnames, idfn, ids, config)
-           for valindex, valset in enumerate(argvalues)]
+def idmaker(argnames, parametersets, idfn=None, ids=None, config=None):
+    ids = [_idvalset(valindex, parameterset, argnames, idfn, ids, config)
+           for valindex, parameterset in enumerate(parametersets)]
     if len(set(ids)) != len(ids):
         # The ids are not unique
         duplicates = [testid for testid in ids if ids.count(testid) > 1]
@@ -983,58 +979,55 @@ def _show_fixtures_per_test(config, session):
     tw = _pytest.config.create_terminal_writer(config)
     verbose = config.getvalue("verbose")
 
-    def get_best_rel(func):
+    def get_best_relpath(func):
         loc = getlocation(func, curdir)
         return curdir.bestrelpath(loc)
 
     def write_fixture(fixture_def):
         argname = fixture_def.argname
-
         if verbose <= 0 and argname.startswith("_"):
             return
         if verbose > 0:
-            bestrel = get_best_rel(fixture_def.func)
+            bestrel = get_best_relpath(fixture_def.func)
             funcargspec = "{0} -- {1}".format(argname, bestrel)
         else:
             funcargspec = argname
         tw.line(funcargspec, green=True)
-
-        INDENT = '    {0}'
         fixture_doc = fixture_def.func.__doc__
-
         if fixture_doc:
-            for line in fixture_doc.strip().split('\n'):
-                tw.line(INDENT.format(line.strip()))
+            write_docstring(tw, fixture_doc)
         else:
-            tw.line(INDENT.format('no docstring available'), red=True)
+            tw.line('    no docstring available', red=True)
 
     def write_item(item):
-        name2fixturedefs = item._fixtureinfo.name2fixturedefs
-
-        if not name2fixturedefs:
-            # The given test item does not use any fixtures
+        try:
+            info = item._fixtureinfo
+        except AttributeError:
+            # doctests items have no _fixtureinfo attribute
+            return
+        if not info.name2fixturedefs:
+            # this test item does not use any fixtures
             return
-        bestrel = get_best_rel(item.function)
-
         tw.line()
         tw.sep('-', 'fixtures used by {0}'.format(item.name))
-        tw.sep('-', '({0})'.format(bestrel))
-        for argname, fixture_defs in sorted(name2fixturedefs.items()):
-            assert fixture_defs is not None
-            if not fixture_defs:
+        tw.sep('-', '({0})'.format(get_best_relpath(item.function)))
+        # dict key not used in loop but needed for sorting
+        for _, fixturedefs in sorted(info.name2fixturedefs.items()):
+            assert fixturedefs is not None
+            if not fixturedefs:
                 continue
-            # The last fixture def item in the list is expected
-            # to be the one used by the test item
-            write_fixture(fixture_defs[-1])
+            # last item is expected to be the one used by the test item
+            write_fixture(fixturedefs[-1])
 
-    for item in session.items:
-        write_item(item)
+    for session_item in session.items:
+        write_item(session_item)
 
 
 def showfixtures(config):
     from _pytest.main import wrap_session
     return wrap_session(config, _showfixtures_main)
 
+
 def _showfixtures_main(config, session):
     import _pytest.config
     session.perform_collect()
@@ -1067,444 +1060,46 @@ def _showfixtures_main(config, session):
         if currentmodule != module:
             if not module.startswith("_pytest."):
                 tw.line()
-                tw.sep("-", "fixtures defined from %s" %(module,))
+                tw.sep("-", "fixtures defined from %s" % (module,))
                 currentmodule = module
         if verbose <= 0 and argname[0] == "_":
             continue
         if verbose > 0:
-            funcargspec = "%s -- %s" %(argname, bestrel,)
+            funcargspec = "%s -- %s" % (argname, bestrel,)
         else:
             funcargspec = argname
         tw.line(funcargspec, green=True)
         loc = getlocation(fixturedef.func, curdir)
         doc = fixturedef.func.__doc__ or ""
         if doc:
-            for line in doc.strip().split("\n"):
-                tw.line("    " + line.strip())
+            write_docstring(tw, doc)
         else:
-            tw.line("    %s: no docstring available" %(loc,),
-                red=True)
-
-
-# builtin pytest.raises helper
-
-def raises(expected_exception, *args, **kwargs):
-    """
-    Assert that a code block/function call raises ``expected_exception``
-    and raise a failure exception otherwise.
-
-    This helper produces a ``ExceptionInfo()`` object (see below).
-
-    If using Python 2.5 or above, you may use this function as a
-    context manager::
-
-        >>> with raises(ZeroDivisionError):
-        ...    1/0
-
-    .. versionchanged:: 2.10
+            tw.line("    %s: no docstring available" % (loc,),
+                    red=True)
 
-    In the context manager form you may use the keyword argument
-    ``message`` to specify a custom failure message::
 
-        >>> with raises(ZeroDivisionError, message="Expecting ZeroDivisionError"):
-        ...    pass
-        Traceback (most recent call last):
-          ...
-        Failed: Expecting ZeroDivisionError
-
-
-    .. note::
-
-       When using ``pytest.raises`` as a context manager, it's worthwhile to
-       note that normal context manager rules apply and that the exception
-       raised *must* be the final line in the scope of the context manager.
-       Lines of code after that, within the scope of the context manager will
-       not be executed. For example::
-
-           >>> value = 15
-           >>> with raises(ValueError) as exc_info:
-           ...     if value > 10:
-           ...         raise ValueError("value must be <= 10")
-           ...     assert str(exc_info.value) == "value must be <= 10"  # this will not execute
-
-       Instead, the following approach must be taken (note the difference in
-       scope)::
-
-           >>> with raises(ValueError) as exc_info:
-           ...     if value > 10:
-           ...         raise ValueError("value must be <= 10")
-           ...
-           >>> assert str(exc_info.value) == "value must be <= 10"
-
-
-    Or you can specify a callable by passing a to-be-called lambda::
-
-        >>> raises(ZeroDivisionError, lambda: 1/0)
-        <ExceptionInfo ...>
-
-    or you can specify an arbitrary callable with arguments::
-
-        >>> def f(x): return 1/x
-        ...
-        >>> raises(ZeroDivisionError, f, 0)
-        <ExceptionInfo ...>
-        >>> raises(ZeroDivisionError, f, x=0)
-        <ExceptionInfo ...>
-
-    A third possibility is to use a string to be executed::
-
-        >>> raises(ZeroDivisionError, "f(0)")
-        <ExceptionInfo ...>
-
-    .. autoclass:: _pytest._code.ExceptionInfo
-        :members:
-
-    .. note::
-        Similar to caught exception objects in Python, explicitly clearing
-        local references to returned ``ExceptionInfo`` objects can
-        help the Python interpreter speed up its garbage collection.
-
-        Clearing those references breaks a reference cycle
-        (``ExceptionInfo`` --> caught exception --> frame stack raising
-        the exception --> current frame stack --> local variables -->
-        ``ExceptionInfo``) which makes Python keep all objects referenced
-        from that cycle (including all local variables in the current
-        frame) alive until the next cyclic garbage collection run. See the
-        official Python ``try`` statement documentation for more detailed
-        information.
-
-    """
-    __tracebackhide__ = True
-    if expected_exception is AssertionError:
-        # we want to catch a AssertionError
-        # replace our subclass with the builtin one
-        # see https://github.com/pytest-dev/pytest/issues/176
-        from _pytest.assertion.util import BuiltinAssertionError \
-            as expected_exception
-    msg = ("exceptions must be old-style classes or"
-           " derived from BaseException, not %s")
-    if isinstance(expected_exception, tuple):
-        for exc in expected_exception:
-            if not isclass(exc):
-                raise TypeError(msg % type(exc))
-    elif not isclass(expected_exception):
-        raise TypeError(msg % type(expected_exception))
-
-    message = "DID NOT RAISE {0}".format(expected_exception)
-
-    if not args:
-        if "message" in kwargs:
-            message = kwargs.pop("message")
-        return RaisesContext(expected_exception, message)
-    elif isinstance(args[0], str):
-        code, = args
-        assert isinstance(code, str)
-        frame = sys._getframe(1)
-        loc = frame.f_locals.copy()
-        loc.update(kwargs)
-        #print "raises frame scope: %r" % frame.f_locals
-        try:
-            code = _pytest._code.Source(code).compile()
-            py.builtin.exec_(code, frame.f_globals, loc)
-            # XXX didn'T mean f_globals == f_locals something special?
-            #     this is destroyed here ...
-        except expected_exception:
-            return _pytest._code.ExceptionInfo()
+def write_docstring(tw, doc):
+    INDENT = "    "
+    doc = doc.rstrip()
+    if "\n" in doc:
+        firstline, rest = doc.split("\n", 1)
     else:
-        func = args[0]
-        try:
-            func(*args[1:], **kwargs)
-        except expected_exception:
-            return _pytest._code.ExceptionInfo()
-    pytest.fail(message)
-
-class RaisesContext(object):
-    def __init__(self, expected_exception, message):
-        self.expected_exception = expected_exception
-        self.message = message
-        self.excinfo = None
-
-    def __enter__(self):
-        self.excinfo = object.__new__(_pytest._code.ExceptionInfo)
-        return self.excinfo
-
-    def __exit__(self, *tp):
-        __tracebackhide__ = True
-        if tp[0] is None:
-            pytest.fail(self.message)
-        if sys.version_info < (2, 7):
-            # py26: on __exit__() exc_value often does not contain the
-            # exception value.
-            # http://bugs.python.org/issue7853
-            if not isinstance(tp[1], BaseException):
-                exc_type, value, traceback = tp
-                tp = exc_type, exc_type(value), traceback
-        self.excinfo.__init__(tp)
-        suppress_exception = issubclass(self.excinfo.type, self.expected_exception)
-        if sys.version_info[0] == 2 and suppress_exception:
-            sys.exc_clear()
-        return suppress_exception
-
-
-# builtin pytest.approx helper
-
-class approx(object):
-    """
-    Assert that two numbers (or two sets of numbers) are equal to each other
-    within some tolerance.
-
-    Due to the `intricacies of floating-point arithmetic`__, numbers that we
-    would intuitively expect to be equal are not always so::
-
-        >>> 0.1 + 0.2 == 0.3
-        False
-
-    __ https://docs.python.org/3/tutorial/floatingpoint.html
-
-    This problem is commonly encountered when writing tests, e.g. when making
-    sure that floating-point values are what you expect them to be.  One way to
-    deal with this problem is to assert that two floating-point numbers are
-    equal to within some appropriate tolerance::
-
-        >>> abs((0.1 + 0.2) - 0.3) < 1e-6
-        True
-
-    However, comparisons like this are tedious to write and difficult to
-    understand.  Furthermore, absolute comparisons like the one above are
-    usually discouraged because there's no tolerance that works well for all
-    situations.  ``1e-6`` is good for numbers around ``1``, but too small for
-    very big numbers and too big for very small ones.  It's better to express
-    the tolerance as a fraction of the expected value, but relative comparisons
-    like that are even more difficult to write correctly and concisely.
-
-    The ``approx`` class performs floating-point comparisons using a syntax
-    that's as intuitive as possible::
-
-        >>> from pytest import approx
-        >>> 0.1 + 0.2 == approx(0.3)
-        True
-
-    The same syntax also works on sequences of numbers::
-
-        >>> (0.1 + 0.2, 0.2 + 0.4) == approx((0.3, 0.6))
-        True
-
-    By default, ``approx`` considers numbers within a relative tolerance of
-    ``1e-6`` (i.e. one part in a million) of its expected value to be equal.
-    This treatment would lead to surprising results if the expected value was
-    ``0.0``, because nothing but ``0.0`` itself is relatively close to ``0.0``.
-    To handle this case less surprisingly, ``approx`` also considers numbers
-    within an absolute tolerance of ``1e-12`` of its expected value to be
-    equal.  Infinite numbers are another special case.  They are only
-    considered equal to themselves, regardless of the relative tolerance.  Both
-    the relative and absolute tolerances can be changed by passing arguments to
-    the ``approx`` constructor::
-
-        >>> 1.0001 == approx(1)
-        False
-        >>> 1.0001 == approx(1, rel=1e-3)
-        True
-        >>> 1.0001 == approx(1, abs=1e-3)
-        True
-
-    If you specify ``abs`` but not ``rel``, the comparison will not consider
-    the relative tolerance at all.  In other words, two numbers that are within
-    the default relative tolerance of ``1e-6`` will still be considered unequal
-    if they exceed the specified absolute tolerance.  If you specify both
-    ``abs`` and ``rel``, the numbers will be considered equal if either
-    tolerance is met::
-
-        >>> 1 + 1e-8 == approx(1)
-        True
-        >>> 1 + 1e-8 == approx(1, abs=1e-12)
-        False
-        >>> 1 + 1e-8 == approx(1, rel=1e-6, abs=1e-12)
-        True
-
-    If you're thinking about using ``approx``, then you might want to know how
-    it compares to other good ways of comparing floating-point numbers.  All of
-    these algorithms are based on relative and absolute tolerances and should
-    agree for the most part, but they do have meaningful differences:
-
-    - ``math.isclose(a, b, rel_tol=1e-9, abs_tol=0.0)``:  True if the relative
-      tolerance is met w.r.t. either ``a`` or ``b`` or if the absolute
-      tolerance is met.  Because the relative tolerance is calculated w.r.t.
-      both ``a`` and ``b``, this test is symmetric (i.e.  neither ``a`` nor
-      ``b`` is a "reference value").  You have to specify an absolute tolerance
-      if you want to compare to ``0.0`` because there is no tolerance by
-      default.  Only available in python>=3.5.  `More information...`__
-
-      __ https://docs.python.org/3/library/math.html#math.isclose
-
-    - ``numpy.isclose(a, b, rtol=1e-5, atol=1e-8)``: True if the difference
-      between ``a`` and ``b`` is less that the sum of the relative tolerance
-      w.r.t. ``b`` and the absolute tolerance.  Because the relative tolerance
-      is only calculated w.r.t. ``b``, this test is asymmetric and you can
-      think of ``b`` as the reference value.  Support for comparing sequences
-      is provided by ``numpy.allclose``.  `More information...`__
-
-      __ http://docs.scipy.org/doc/numpy-1.10.0/reference/generated/numpy.isclose.html
-
-    - ``unittest.TestCase.assertAlmostEqual(a, b)``: True if ``a`` and ``b``
-      are within an absolute tolerance of ``1e-7``.  No relative tolerance is
-      considered and the absolute tolerance cannot be changed, so this function
-      is not appropriate for very large or very small numbers.  Also, it's only
-      available in subclasses of ``unittest.TestCase`` and it's ugly because it
-      doesn't follow PEP8.  `More information...`__
-
-      __ https://docs.python.org/3/library/unittest.html#unittest.TestCase.assertAlmostEqual
-
-    - ``a == pytest.approx(b, rel=1e-6, abs=1e-12)``: True if the relative
-      tolerance is met w.r.t. ``b`` or if the absolute tolerance is met.
-      Because the relative tolerance is only calculated w.r.t. ``b``, this test
-      is asymmetric and you can think of ``b`` as the reference value.  In the
-      special case that you explicitly specify an absolute tolerance but not a
-      relative tolerance, only the absolute tolerance is considered.
-    """
-
-    def __init__(self, expected, rel=None, abs=None):
-        self.expected = expected
-        self.abs = abs
-        self.rel = rel
+        firstline, rest = doc, ""
 
-    def __repr__(self):
-        return ', '.join(repr(x) for x in self.expected)
-
-    def __eq__(self, actual):
-        from collections import Iterable
-        if not isinstance(actual, Iterable):
-            actual = [actual]
-        if len(actual) != len(self.expected):
-            return False
-        return all(a == x for a, x in zip(actual, self.expected))
+    if firstline.strip():
+        tw.line(INDENT + firstline.strip())
 
-    __hash__ = None
+    if rest:
+        for line in dedent(rest).split("\n"):
+            tw.write(INDENT + line + "\n")
 
-    def __ne__(self, actual):
-        return not (actual == self)
-
-    @property
-    def expected(self):
-        # Regardless of whether the user-specified expected value is a number
-        # or a sequence of numbers, return a list of ApproxNotIterable objects
-        # that can be compared against.
-        from collections import Iterable
-        approx_non_iter = lambda x: ApproxNonIterable(x, self.rel, self.abs)
-        if isinstance(self._expected, Iterable):
-            return [approx_non_iter(x) for x in self._expected]
-        else:
-            return [approx_non_iter(self._expected)]
 
-    @expected.setter
-    def expected(self, expected):
-        self._expected = expected
-
-
-class ApproxNonIterable(object):
-    """
-    Perform approximate comparisons for single numbers only.
-
-    In other words, the ``expected`` attribute for objects of this class must
-    be some sort of number.  This is in contrast to the ``approx`` class, where
-    the ``expected`` attribute can either be a number of a sequence of numbers.
-    This class is responsible for making comparisons, while ``approx`` is
-    responsible for abstracting the difference between numbers and sequences of
-    numbers.  Although this class can stand on its own, it's only meant to be
-    used within ``approx``.
-    """
-
-    def __init__(self, expected, rel=None, abs=None):
-        self.expected = expected
-        self.abs = abs
-        self.rel = rel
-
-    def __repr__(self):
-        if isinstance(self.expected, complex):
-            return str(self.expected)
-
-        # Infinities aren't compared using tolerances, so don't show a
-        # tolerance.
-        if math.isinf(self.expected):
-            return str(self.expected)
-
-        # If a sensible tolerance can't be calculated, self.tolerance will
-        # raise a ValueError.  In this case, display '???'.
-        try:
-            vetted_tolerance = '{:.1e}'.format(self.tolerance)
-        except ValueError:
-            vetted_tolerance = '???'
-
-        if sys.version_info[0] == 2:
-            return '{0} +- {1}'.format(self.expected, vetted_tolerance)
-        else:
-            return u'{0} \u00b1 {1}'.format(self.expected, vetted_tolerance)
-
-    def __eq__(self, actual):
-        # Short-circuit exact equality.
-        if actual == self.expected:
-            return True
-
-        # Infinity shouldn't be approximately equal to anything but itself, but
-        # if there's a relative tolerance, it will be infinite and infinity
-        # will seem approximately equal to everything.  The equal-to-itself
-        # case would have been short circuited above, so here we can just
-        # return false if the expected value is infinite.  The abs() call is
-        # for compatibility with complex numbers.
-        if math.isinf(abs(self.expected)):
-            return False
-
-        # Return true if the two numbers are within the tolerance.
-        return abs(self.expected - actual) <= self.tolerance
-
-    __hash__ = None
-
-    def __ne__(self, actual):
-        return not (actual == self)
-
-    @property
-    def tolerance(self):
-        set_default = lambda x, default: x if x is not None else default
-
-        # Figure out what the absolute tolerance should be.  ``self.abs`` is
-        # either None or a value specified by the user.
-        absolute_tolerance = set_default(self.abs, 1e-12)
-
-        if absolute_tolerance < 0:
-            raise ValueError("absolute tolerance can't be negative: {0}".format(absolute_tolerance))
-        if math.isnan(absolute_tolerance):
-            raise ValueError("absolute tolerance can't be NaN.")
-
-        # If the user specified an absolute tolerance but not a relative one,
-        # just return the absolute tolerance.
-        if self.rel is None:
-            if self.abs is not None:
-                return absolute_tolerance
-
-        # Figure out what the relative tolerance should be.  ``self.rel`` is
-        # either None or a value specified by the user.  This is done after
-        # we've made sure the user didn't ask for an absolute tolerance only,
-        # because we don't want to raise errors about the relative tolerance if
-        # we aren't even going to use it.
-        relative_tolerance = set_default(self.rel, 1e-6) * abs(self.expected)
-
-        if relative_tolerance < 0:
-            raise ValueError("relative tolerance can't be negative: {0}".format(absolute_tolerance))
-        if math.isnan(relative_tolerance):
-            raise ValueError("relative tolerance can't be NaN.")
-
-        # Return the larger of the relative and absolute tolerances.
-        return max(relative_tolerance, absolute_tolerance)
-
-
-#
-#  the basic pytest Function item
-#
-
-class Function(FunctionMixin, pytest.Item, fixtures.FuncargnamesCompatAttr):
+class Function(FunctionMixin, main.Item, fixtures.FuncargnamesCompatAttr):
     """ a Function Item is responsible for setting up and executing a
     Python test function.
     """
     _genid = None
+
     def __init__(self, name, parent, args=None, config=None,
                  callspec=None, callobj=NOTSET, keywords=None, session=None,
                  fixtureinfo=None, originalname=None):
@@ -1556,7 +1151,7 @@ class Function(FunctionMixin, pytest.Item, fixtures.FuncargnamesCompatAttr):
 
     def _getobj(self):
         name = self.name
-        i = name.find("[") # parametrization
+        i = name.find("[")  # parametrization
         if i != -1:
             name = name[:i]
         return getattr(self.parent.obj, name)
diff --git a/lib/spack/external/_pytest/python_api.py b/lib/spack/external/_pytest/python_api.py
new file mode 100644
index 0000000000..cfc01193b0
--- /dev/null
+++ b/lib/spack/external/_pytest/python_api.py
@@ -0,0 +1,626 @@
+import math
+import sys
+
+import py
+
+from _pytest.compat import isclass, izip
+from _pytest.outcomes import fail
+import _pytest._code
+
+
+def _cmp_raises_type_error(self, other):
+    """__cmp__ implementation which raises TypeError. Used
+    by Approx base classes to implement only == and != and raise a
+    TypeError for other comparisons.
+
+    Needed in Python 2 only, Python 3 all it takes is not implementing the
+    other operators at all.
+    """
+    __tracebackhide__ = True
+    raise TypeError('Comparison operators other than == and != not supported by approx objects')
+
+
+# builtin pytest.approx helper
+
+
+class ApproxBase(object):
+    """
+    Provide shared utilities for making approximate comparisons between numbers
+    or sequences of numbers.
+    """
+
+    def __init__(self, expected, rel=None, abs=None, nan_ok=False):
+        self.expected = expected
+        self.abs = abs
+        self.rel = rel
+        self.nan_ok = nan_ok
+
+    def __repr__(self):
+        raise NotImplementedError
+
+    def __eq__(self, actual):
+        return all(
+            a == self._approx_scalar(x)
+            for a, x in self._yield_comparisons(actual))
+
+    __hash__ = None
+
+    def __ne__(self, actual):
+        return not (actual == self)
+
+    if sys.version_info[0] == 2:
+        __cmp__ = _cmp_raises_type_error
+
+    def _approx_scalar(self, x):
+        return ApproxScalar(x, rel=self.rel, abs=self.abs, nan_ok=self.nan_ok)
+
+    def _yield_comparisons(self, actual):
+        """
+        Yield all the pairs of numbers to be compared.  This is used to
+        implement the `__eq__` method.
+        """
+        raise NotImplementedError
+
+
+class ApproxNumpy(ApproxBase):
+    """
+    Perform approximate comparisons for numpy arrays.
+    """
+
+    # Tell numpy to use our `__eq__` operator instead of its.
+    __array_priority__ = 100
+
+    def __repr__(self):
+        # It might be nice to rewrite this function to account for the
+        # shape of the array...
+        return "approx({0!r})".format(list(
+            self._approx_scalar(x) for x in self.expected))
+
+    if sys.version_info[0] == 2:
+        __cmp__ = _cmp_raises_type_error
+
+    def __eq__(self, actual):
+        import numpy as np
+
+        try:
+            actual = np.asarray(actual)
+        except:  # noqa
+            raise TypeError("cannot compare '{0}' to numpy.ndarray".format(actual))
+
+        if actual.shape != self.expected.shape:
+            return False
+
+        return ApproxBase.__eq__(self, actual)
+
+    def _yield_comparisons(self, actual):
+        import numpy as np
+
+        # We can be sure that `actual` is a numpy array, because it's
+        # casted in `__eq__` before being passed to `ApproxBase.__eq__`,
+        # which is the only method that calls this one.
+        for i in np.ndindex(self.expected.shape):
+            yield actual[i], self.expected[i]
+
+
+class ApproxMapping(ApproxBase):
+    """
+    Perform approximate comparisons for mappings where the values are numbers
+    (the keys can be anything).
+    """
+
+    def __repr__(self):
+        return "approx({0!r})".format(dict(
+            (k, self._approx_scalar(v))
+            for k, v in self.expected.items()))
+
+    def __eq__(self, actual):
+        if set(actual.keys()) != set(self.expected.keys()):
+            return False
+
+        return ApproxBase.__eq__(self, actual)
+
+    def _yield_comparisons(self, actual):
+        for k in self.expected.keys():
+            yield actual[k], self.expected[k]
+
+
+class ApproxSequence(ApproxBase):
+    """
+    Perform approximate comparisons for sequences of numbers.
+    """
+
+    # Tell numpy to use our `__eq__` operator instead of its.
+    __array_priority__ = 100
+
+    def __repr__(self):
+        seq_type = type(self.expected)
+        if seq_type not in (tuple, list, set):
+            seq_type = list
+        return "approx({0!r})".format(seq_type(
+            self._approx_scalar(x) for x in self.expected))
+
+    def __eq__(self, actual):
+        if len(actual) != len(self.expected):
+            return False
+        return ApproxBase.__eq__(self, actual)
+
+    def _yield_comparisons(self, actual):
+        return izip(actual, self.expected)
+
+
+class ApproxScalar(ApproxBase):
+    """
+    Perform approximate comparisons for single numbers only.
+    """
+
+    def __repr__(self):
+        """
+        Return a string communicating both the expected value and the tolerance
+        for the comparison being made, e.g. '1.0 +- 1e-6'.  Use the unicode
+        plus/minus symbol if this is python3 (it's too hard to get right for
+        python2).
+        """
+        if isinstance(self.expected, complex):
+            return str(self.expected)
+
+        # Infinities aren't compared using tolerances, so don't show a
+        # tolerance.
+        if math.isinf(self.expected):
+            return str(self.expected)
+
+        # If a sensible tolerance can't be calculated, self.tolerance will
+        # raise a ValueError.  In this case, display '???'.
+        try:
+            vetted_tolerance = '{:.1e}'.format(self.tolerance)
+        except ValueError:
+            vetted_tolerance = '???'
+
+        if sys.version_info[0] == 2:
+            return '{0} +- {1}'.format(self.expected, vetted_tolerance)
+        else:
+            return u'{0} \u00b1 {1}'.format(self.expected, vetted_tolerance)
+
+    def __eq__(self, actual):
+        """
+        Return true if the given value is equal to the expected value within
+        the pre-specified tolerance.
+        """
+
+        # Short-circuit exact equality.
+        if actual == self.expected:
+            return True
+
+        # Allow the user to control whether NaNs are considered equal to each
+        # other or not.  The abs() calls are for compatibility with complex
+        # numbers.
+        if math.isnan(abs(self.expected)):
+            return self.nan_ok and math.isnan(abs(actual))
+
+        # Infinity shouldn't be approximately equal to anything but itself, but
+        # if there's a relative tolerance, it will be infinite and infinity
+        # will seem approximately equal to everything.  The equal-to-itself
+        # case would have been short circuited above, so here we can just
+        # return false if the expected value is infinite.  The abs() call is
+        # for compatibility with complex numbers.
+        if math.isinf(abs(self.expected)):
+            return False
+
+        # Return true if the two numbers are within the tolerance.
+        return abs(self.expected - actual) <= self.tolerance
+
+    __hash__ = None
+
+    @property
+    def tolerance(self):
+        """
+        Return the tolerance for the comparison.  This could be either an
+        absolute tolerance or a relative tolerance, depending on what the user
+        specified or which would be larger.
+        """
+        def set_default(x, default):
+            return x if x is not None else default
+
+        # Figure out what the absolute tolerance should be.  ``self.abs`` is
+        # either None or a value specified by the user.
+        absolute_tolerance = set_default(self.abs, 1e-12)
+
+        if absolute_tolerance < 0:
+            raise ValueError("absolute tolerance can't be negative: {0}".format(absolute_tolerance))
+        if math.isnan(absolute_tolerance):
+            raise ValueError("absolute tolerance can't be NaN.")
+
+        # If the user specified an absolute tolerance but not a relative one,
+        # just return the absolute tolerance.
+        if self.rel is None:
+            if self.abs is not None:
+                return absolute_tolerance
+
+        # Figure out what the relative tolerance should be.  ``self.rel`` is
+        # either None or a value specified by the user.  This is done after
+        # we've made sure the user didn't ask for an absolute tolerance only,
+        # because we don't want to raise errors about the relative tolerance if
+        # we aren't even going to use it.
+        relative_tolerance = set_default(self.rel, 1e-6) * abs(self.expected)
+
+        if relative_tolerance < 0:
+            raise ValueError("relative tolerance can't be negative: {0}".format(absolute_tolerance))
+        if math.isnan(relative_tolerance):
+            raise ValueError("relative tolerance can't be NaN.")
+
+        # Return the larger of the relative and absolute tolerances.
+        return max(relative_tolerance, absolute_tolerance)
+
+
+def approx(expected, rel=None, abs=None, nan_ok=False):
+    """
+    Assert that two numbers (or two sets of numbers) are equal to each other
+    within some tolerance.
+
+    Due to the `intricacies of floating-point arithmetic`__, numbers that we
+    would intuitively expect to be equal are not always so::
+
+        >>> 0.1 + 0.2 == 0.3
+        False
+
+    __ https://docs.python.org/3/tutorial/floatingpoint.html
+
+    This problem is commonly encountered when writing tests, e.g. when making
+    sure that floating-point values are what you expect them to be.  One way to
+    deal with this problem is to assert that two floating-point numbers are
+    equal to within some appropriate tolerance::
+
+        >>> abs((0.1 + 0.2) - 0.3) < 1e-6
+        True
+
+    However, comparisons like this are tedious to write and difficult to
+    understand.  Furthermore, absolute comparisons like the one above are
+    usually discouraged because there's no tolerance that works well for all
+    situations.  ``1e-6`` is good for numbers around ``1``, but too small for
+    very big numbers and too big for very small ones.  It's better to express
+    the tolerance as a fraction of the expected value, but relative comparisons
+    like that are even more difficult to write correctly and concisely.
+
+    The ``approx`` class performs floating-point comparisons using a syntax
+    that's as intuitive as possible::
+
+        >>> from pytest import approx
+        >>> 0.1 + 0.2 == approx(0.3)
+        True
+
+    The same syntax also works for sequences of numbers::
+
+        >>> (0.1 + 0.2, 0.2 + 0.4) == approx((0.3, 0.6))
+        True
+
+    Dictionary *values*::
+
+        >>> {'a': 0.1 + 0.2, 'b': 0.2 + 0.4} == approx({'a': 0.3, 'b': 0.6})
+        True
+
+    And ``numpy`` arrays::
+
+        >>> import numpy as np                                                          # doctest: +SKIP
+        >>> np.array([0.1, 0.2]) + np.array([0.2, 0.4]) == approx(np.array([0.3, 0.6])) # doctest: +SKIP
+        True
+
+    By default, ``approx`` considers numbers within a relative tolerance of
+    ``1e-6`` (i.e. one part in a million) of its expected value to be equal.
+    This treatment would lead to surprising results if the expected value was
+    ``0.0``, because nothing but ``0.0`` itself is relatively close to ``0.0``.
+    To handle this case less surprisingly, ``approx`` also considers numbers
+    within an absolute tolerance of ``1e-12`` of its expected value to be
+    equal.  Infinity and NaN are special cases.  Infinity is only considered
+    equal to itself, regardless of the relative tolerance.  NaN is not
+    considered equal to anything by default, but you can make it be equal to
+    itself by setting the ``nan_ok`` argument to True.  (This is meant to
+    facilitate comparing arrays that use NaN to mean "no data".)
+
+    Both the relative and absolute tolerances can be changed by passing
+    arguments to the ``approx`` constructor::
+
+        >>> 1.0001 == approx(1)
+        False
+        >>> 1.0001 == approx(1, rel=1e-3)
+        True
+        >>> 1.0001 == approx(1, abs=1e-3)
+        True
+
+    If you specify ``abs`` but not ``rel``, the comparison will not consider
+    the relative tolerance at all.  In other words, two numbers that are within
+    the default relative tolerance of ``1e-6`` will still be considered unequal
+    if they exceed the specified absolute tolerance.  If you specify both
+    ``abs`` and ``rel``, the numbers will be considered equal if either
+    tolerance is met::
+
+        >>> 1 + 1e-8 == approx(1)
+        True
+        >>> 1 + 1e-8 == approx(1, abs=1e-12)
+        False
+        >>> 1 + 1e-8 == approx(1, rel=1e-6, abs=1e-12)
+        True
+
+    If you're thinking about using ``approx``, then you might want to know how
+    it compares to other good ways of comparing floating-point numbers.  All of
+    these algorithms are based on relative and absolute tolerances and should
+    agree for the most part, but they do have meaningful differences:
+
+    - ``math.isclose(a, b, rel_tol=1e-9, abs_tol=0.0)``:  True if the relative
+      tolerance is met w.r.t. either ``a`` or ``b`` or if the absolute
+      tolerance is met.  Because the relative tolerance is calculated w.r.t.
+      both ``a`` and ``b``, this test is symmetric (i.e.  neither ``a`` nor
+      ``b`` is a "reference value").  You have to specify an absolute tolerance
+      if you want to compare to ``0.0`` because there is no tolerance by
+      default.  Only available in python>=3.5.  `More information...`__
+
+      __ https://docs.python.org/3/library/math.html#math.isclose
+
+    - ``numpy.isclose(a, b, rtol=1e-5, atol=1e-8)``: True if the difference
+      between ``a`` and ``b`` is less that the sum of the relative tolerance
+      w.r.t. ``b`` and the absolute tolerance.  Because the relative tolerance
+      is only calculated w.r.t. ``b``, this test is asymmetric and you can
+      think of ``b`` as the reference value.  Support for comparing sequences
+      is provided by ``numpy.allclose``.  `More information...`__
+
+      __ http://docs.scipy.org/doc/numpy-1.10.0/reference/generated/numpy.isclose.html
+
+    - ``unittest.TestCase.assertAlmostEqual(a, b)``: True if ``a`` and ``b``
+      are within an absolute tolerance of ``1e-7``.  No relative tolerance is
+      considered and the absolute tolerance cannot be changed, so this function
+      is not appropriate for very large or very small numbers.  Also, it's only
+      available in subclasses of ``unittest.TestCase`` and it's ugly because it
+      doesn't follow PEP8.  `More information...`__
+
+      __ https://docs.python.org/3/library/unittest.html#unittest.TestCase.assertAlmostEqual
+
+    - ``a == pytest.approx(b, rel=1e-6, abs=1e-12)``: True if the relative
+      tolerance is met w.r.t. ``b`` or if the absolute tolerance is met.
+      Because the relative tolerance is only calculated w.r.t. ``b``, this test
+      is asymmetric and you can think of ``b`` as the reference value.  In the
+      special case that you explicitly specify an absolute tolerance but not a
+      relative tolerance, only the absolute tolerance is considered.
+
+    .. warning::
+
+       .. versionchanged:: 3.2
+
+       In order to avoid inconsistent behavior, ``TypeError`` is
+       raised for ``>``, ``>=``, ``<`` and ``<=`` comparisons.
+       The example below illustrates the problem::
+
+           assert approx(0.1) > 0.1 + 1e-10  # calls approx(0.1).__gt__(0.1 + 1e-10)
+           assert 0.1 + 1e-10 > approx(0.1)  # calls approx(0.1).__lt__(0.1 + 1e-10)
+
+       In the second example one expects ``approx(0.1).__le__(0.1 + 1e-10)``
+       to be called. But instead, ``approx(0.1).__lt__(0.1 + 1e-10)`` is used to
+       comparison. This is because the call hierarchy of rich comparisons
+       follows a fixed behavior. `More information...`__
+
+       __ https://docs.python.org/3/reference/datamodel.html#object.__ge__
+    """
+
+    from collections import Mapping, Sequence
+    from _pytest.compat import STRING_TYPES as String
+
+    # Delegate the comparison to a class that knows how to deal with the type
+    # of the expected value (e.g. int, float, list, dict, numpy.array, etc).
+    #
+    # This architecture is really driven by the need to support numpy arrays.
+    # The only way to override `==` for arrays without requiring that approx be
+    # the left operand is to inherit the approx object from `numpy.ndarray`.
+    # But that can't be a general solution, because it requires (1) numpy to be
+    # installed and (2) the expected value to be a numpy array.  So the general
+    # solution is to delegate each type of expected value to a different class.
+    #
+    # This has the advantage that it made it easy to support mapping types
+    # (i.e. dict).  The old code accepted mapping types, but would only compare
+    # their keys, which is probably not what most people would expect.
+
+    if _is_numpy_array(expected):
+        cls = ApproxNumpy
+    elif isinstance(expected, Mapping):
+        cls = ApproxMapping
+    elif isinstance(expected, Sequence) and not isinstance(expected, String):
+        cls = ApproxSequence
+    else:
+        cls = ApproxScalar
+
+    return cls(expected, rel, abs, nan_ok)
+
+
+def _is_numpy_array(obj):
+    """
+    Return true if the given object is a numpy array.  Make a special effort to
+    avoid importing numpy unless it's really necessary.
+    """
+    import inspect
+
+    for cls in inspect.getmro(type(obj)):
+        if cls.__module__ == 'numpy':
+            try:
+                import numpy as np
+                return isinstance(obj, np.ndarray)
+            except ImportError:
+                pass
+
+    return False
+
+
+# builtin pytest.raises helper
+
+def raises(expected_exception, *args, **kwargs):
+    """
+    Assert that a code block/function call raises ``expected_exception``
+    and raise a failure exception otherwise.
+
+    This helper produces a ``ExceptionInfo()`` object (see below).
+
+    If using Python 2.5 or above, you may use this function as a
+    context manager::
+
+        >>> with raises(ZeroDivisionError):
+        ...    1/0
+
+    .. versionchanged:: 2.10
+
+    In the context manager form you may use the keyword argument
+    ``message`` to specify a custom failure message::
+
+        >>> with raises(ZeroDivisionError, message="Expecting ZeroDivisionError"):
+        ...    pass
+        Traceback (most recent call last):
+          ...
+        Failed: Expecting ZeroDivisionError
+
+    .. note::
+
+       When using ``pytest.raises`` as a context manager, it's worthwhile to
+       note that normal context manager rules apply and that the exception
+       raised *must* be the final line in the scope of the context manager.
+       Lines of code after that, within the scope of the context manager will
+       not be executed. For example::
+
+           >>> value = 15
+           >>> with raises(ValueError) as exc_info:
+           ...     if value > 10:
+           ...         raise ValueError("value must be <= 10")
+           ...     assert exc_info.type == ValueError  # this will not execute
+
+       Instead, the following approach must be taken (note the difference in
+       scope)::
+
+           >>> with raises(ValueError) as exc_info:
+           ...     if value > 10:
+           ...         raise ValueError("value must be <= 10")
+           ...
+           >>> assert exc_info.type == ValueError
+
+
+    Since version ``3.1`` you can use the keyword argument ``match`` to assert that the
+    exception matches a text or regex::
+
+        >>> with raises(ValueError, match='must be 0 or None'):
+        ...     raise ValueError("value must be 0 or None")
+
+        >>> with raises(ValueError, match=r'must be \d+$'):
+        ...     raise ValueError("value must be 42")
+
+    **Legacy forms**
+
+    The forms below are fully supported but are discouraged for new code because the
+    context manager form is regarded as more readable and less error-prone.
+
+    It is possible to specify a callable by passing a to-be-called lambda::
+
+        >>> raises(ZeroDivisionError, lambda: 1/0)
+        <ExceptionInfo ...>
+
+    or you can specify an arbitrary callable with arguments::
+
+        >>> def f(x): return 1/x
+        ...
+        >>> raises(ZeroDivisionError, f, 0)
+        <ExceptionInfo ...>
+        >>> raises(ZeroDivisionError, f, x=0)
+        <ExceptionInfo ...>
+
+    It is also possible to pass a string to be evaluated at runtime::
+
+        >>> raises(ZeroDivisionError, "f(0)")
+        <ExceptionInfo ...>
+
+    The string will be evaluated using the same ``locals()`` and ``globals()``
+    at the moment of the ``raises`` call.
+
+    .. autoclass:: _pytest._code.ExceptionInfo
+        :members:
+
+    .. note::
+        Similar to caught exception objects in Python, explicitly clearing
+        local references to returned ``ExceptionInfo`` objects can
+        help the Python interpreter speed up its garbage collection.
+
+        Clearing those references breaks a reference cycle
+        (``ExceptionInfo`` --> caught exception --> frame stack raising
+        the exception --> current frame stack --> local variables -->
+        ``ExceptionInfo``) which makes Python keep all objects referenced
+        from that cycle (including all local variables in the current
+        frame) alive until the next cyclic garbage collection run. See the
+        official Python ``try`` statement documentation for more detailed
+        information.
+
+    """
+    __tracebackhide__ = True
+    msg = ("exceptions must be old-style classes or"
+           " derived from BaseException, not %s")
+    if isinstance(expected_exception, tuple):
+        for exc in expected_exception:
+            if not isclass(exc):
+                raise TypeError(msg % type(exc))
+    elif not isclass(expected_exception):
+        raise TypeError(msg % type(expected_exception))
+
+    message = "DID NOT RAISE {0}".format(expected_exception)
+    match_expr = None
+
+    if not args:
+        if "message" in kwargs:
+            message = kwargs.pop("message")
+        if "match" in kwargs:
+            match_expr = kwargs.pop("match")
+            message += " matching '{0}'".format(match_expr)
+        return RaisesContext(expected_exception, message, match_expr)
+    elif isinstance(args[0], str):
+        code, = args
+        assert isinstance(code, str)
+        frame = sys._getframe(1)
+        loc = frame.f_locals.copy()
+        loc.update(kwargs)
+        # print "raises frame scope: %r" % frame.f_locals
+        try:
+            code = _pytest._code.Source(code).compile()
+            py.builtin.exec_(code, frame.f_globals, loc)
+            # XXX didn'T mean f_globals == f_locals something special?
+            #     this is destroyed here ...
+        except expected_exception:
+            return _pytest._code.ExceptionInfo()
+    else:
+        func = args[0]
+        try:
+            func(*args[1:], **kwargs)
+        except expected_exception:
+            return _pytest._code.ExceptionInfo()
+    fail(message)
+
+
+raises.Exception = fail.Exception
+
+
+class RaisesContext(object):
+    def __init__(self, expected_exception, message, match_expr):
+        self.expected_exception = expected_exception
+        self.message = message
+        self.match_expr = match_expr
+        self.excinfo = None
+
+    def __enter__(self):
+        self.excinfo = object.__new__(_pytest._code.ExceptionInfo)
+        return self.excinfo
+
+    def __exit__(self, *tp):
+        __tracebackhide__ = True
+        if tp[0] is None:
+            fail(self.message)
+        if sys.version_info < (2, 7):
+            # py26: on __exit__() exc_value often does not contain the
+            # exception value.
+            # http://bugs.python.org/issue7853
+            if not isinstance(tp[1], BaseException):
+                exc_type, value, traceback = tp
+                tp = exc_type, exc_type(value), traceback
+        self.excinfo.__init__(tp)
+        suppress_exception = issubclass(self.excinfo.type, self.expected_exception)
+        if sys.version_info[0] == 2 and suppress_exception:
+            sys.exc_clear()
+        if self.match_expr:
+            self.excinfo.match(self.match_expr)
+        return suppress_exception
diff --git a/lib/spack/external/_pytest/recwarn.py b/lib/spack/external/_pytest/recwarn.py
index 87823bfbc6..c9fa872c07 100644
--- a/lib/spack/external/_pytest/recwarn.py
+++ b/lib/spack/external/_pytest/recwarn.py
@@ -1,4 +1,5 @@
 """ recording warnings during test function execution. """
+from __future__ import absolute_import, division, print_function
 
 import inspect
 
@@ -6,11 +7,13 @@ import _pytest._code
 import py
 import sys
 import warnings
-import pytest
 
+from _pytest.fixtures import yield_fixture
+from _pytest.outcomes import fail
 
-@pytest.yield_fixture
-def recwarn(request):
+
+@yield_fixture
+def recwarn():
     """Return a WarningsRecorder instance that provides these methods:
 
     * ``pop(category=None)``: return last warning matching the category.
@@ -25,16 +28,9 @@ def recwarn(request):
         yield wrec
 
 
-def pytest_namespace():
-    return {'deprecated_call': deprecated_call,
-            'warns': warns}
-
-
 def deprecated_call(func=None, *args, **kwargs):
-    """ assert that calling ``func(*args, **kwargs)`` triggers a
-    ``DeprecationWarning`` or ``PendingDeprecationWarning``.
-
-    This function can be used as a context manager::
+    """context manager that can be used to ensure a block of code triggers a
+    ``DeprecationWarning`` or ``PendingDeprecationWarning``::
 
         >>> import warnings
         >>> def api_call_v2():
@@ -44,40 +40,47 @@ def deprecated_call(func=None, *args, **kwargs):
         >>> with deprecated_call():
         ...    assert api_call_v2() == 200
 
-    Note: we cannot use WarningsRecorder here because it is still subject
-    to the mechanism that prevents warnings of the same type from being
-    triggered twice for the same module. See #1190.
+    ``deprecated_call`` can also be used by passing a function and ``*args`` and ``*kwargs``,
+    in which case it will ensure calling ``func(*args, **kwargs)`` produces one of the warnings
+    types above.
     """
     if not func:
-        return WarningsChecker(expected_warning=DeprecationWarning)
+        return _DeprecatedCallContext()
+    else:
+        __tracebackhide__ = True
+        with _DeprecatedCallContext():
+            return func(*args, **kwargs)
+
 
-    categories = []
+class _DeprecatedCallContext(object):
+    """Implements the logic to capture deprecation warnings as a context manager."""
 
-    def warn_explicit(message, category, *args, **kwargs):
-        categories.append(category)
-        old_warn_explicit(message, category, *args, **kwargs)
+    def __enter__(self):
+        self._captured_categories = []
+        self._old_warn = warnings.warn
+        self._old_warn_explicit = warnings.warn_explicit
+        warnings.warn_explicit = self._warn_explicit
+        warnings.warn = self._warn
 
-    def warn(message, category=None, *args, **kwargs):
+    def _warn_explicit(self, message, category, *args, **kwargs):
+        self._captured_categories.append(category)
+
+    def _warn(self, message, category=None, *args, **kwargs):
         if isinstance(message, Warning):
-            categories.append(message.__class__)
+            self._captured_categories.append(message.__class__)
         else:
-            categories.append(category)
-        old_warn(message, category, *args, **kwargs)
-
-    old_warn = warnings.warn
-    old_warn_explicit = warnings.warn_explicit
-    warnings.warn_explicit = warn_explicit
-    warnings.warn = warn
-    try:
-        ret = func(*args, **kwargs)
-    finally:
-        warnings.warn_explicit = old_warn_explicit
-        warnings.warn = old_warn
-    deprecation_categories = (DeprecationWarning, PendingDeprecationWarning)
-    if not any(issubclass(c, deprecation_categories) for c in categories):
-        __tracebackhide__ = True
-        raise AssertionError("%r did not produce DeprecationWarning" % (func,))
-    return ret
+            self._captured_categories.append(category)
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        warnings.warn_explicit = self._old_warn_explicit
+        warnings.warn = self._old_warn
+
+        if exc_type is None:
+            deprecation_categories = (DeprecationWarning, PendingDeprecationWarning)
+            if not any(issubclass(c, deprecation_categories) for c in self._captured_categories):
+                __tracebackhide__ = True
+                msg = "Did not produce DeprecationWarning or PendingDeprecationWarning"
+                raise AssertionError(msg)
 
 
 def warns(expected_warning, *args, **kwargs):
@@ -115,24 +118,14 @@ def warns(expected_warning, *args, **kwargs):
             return func(*args[1:], **kwargs)
 
 
-class RecordedWarning(object):
-    def __init__(self, message, category, filename, lineno, file, line):
-        self.message = message
-        self.category = category
-        self.filename = filename
-        self.lineno = lineno
-        self.file = file
-        self.line = line
-
-
-class WarningsRecorder(object):
+class WarningsRecorder(warnings.catch_warnings):
     """A context manager to record raised warnings.
 
     Adapted from `warnings.catch_warnings`.
     """
 
-    def __init__(self, module=None):
-        self._module = sys.modules['warnings'] if module is None else module
+    def __init__(self):
+        super(WarningsRecorder, self).__init__(record=True)
         self._entered = False
         self._list = []
 
@@ -169,38 +162,20 @@ class WarningsRecorder(object):
         if self._entered:
             __tracebackhide__ = True
             raise RuntimeError("Cannot enter %r twice" % self)
-        self._entered = True
-        self._filters = self._module.filters
-        self._module.filters = self._filters[:]
-        self._showwarning = self._module.showwarning
-
-        def showwarning(message, category, filename, lineno,
-                        file=None, line=None):
-            self._list.append(RecordedWarning(
-                message, category, filename, lineno, file, line))
-
-            # still perform old showwarning functionality
-            self._showwarning(
-                message, category, filename, lineno, file=file, line=line)
-
-        self._module.showwarning = showwarning
-
-        # allow the same warning to be raised more than once
-
-        self._module.simplefilter('always')
+        self._list = super(WarningsRecorder, self).__enter__()
+        warnings.simplefilter('always')
         return self
 
     def __exit__(self, *exc_info):
         if not self._entered:
             __tracebackhide__ = True
             raise RuntimeError("Cannot exit %r without entering first" % self)
-        self._module.filters = self._filters
-        self._module.showwarning = self._showwarning
+        super(WarningsRecorder, self).__exit__(*exc_info)
 
 
 class WarningsChecker(WarningsRecorder):
-    def __init__(self, expected_warning=None, module=None):
-        super(WarningsChecker, self).__init__(module=module)
+    def __init__(self, expected_warning=None):
+        super(WarningsChecker, self).__init__()
 
         msg = ("exceptions must be old-style classes or "
                "derived from Warning, not %s")
@@ -221,6 +196,10 @@ class WarningsChecker(WarningsRecorder):
         # only check if we're not currently handling an exception
         if all(a is None for a in exc_info):
             if self.expected_warning is not None:
-                if not any(r.category in self.expected_warning for r in self):
+                if not any(issubclass(r.category, self.expected_warning)
+                           for r in self):
                     __tracebackhide__ = True
-                    pytest.fail("DID NOT WARN")
+                    fail("DID NOT WARN. No warnings of type {0} was emitted. "
+                         "The list of emitted warnings is: {1}.".format(
+                             self.expected_warning,
+                             [each.message for each in self]))
diff --git a/lib/spack/external/_pytest/resultlog.py b/lib/spack/external/_pytest/resultlog.py
index fc00259834..9f9c2d1f65 100644
--- a/lib/spack/external/_pytest/resultlog.py
+++ b/lib/spack/external/_pytest/resultlog.py
@@ -1,15 +1,18 @@
 """ log machine-parseable test session result information in a plain
 text file.
 """
+from __future__ import absolute_import, division, print_function
 
 import py
 import os
 
+
 def pytest_addoption(parser):
     group = parser.getgroup("terminal reporting", "resultlog plugin options")
     group.addoption('--resultlog', '--result-log', action="store",
-        metavar="path", default=None,
-        help="DEPRECATED path for machine-readable result log.")
+                    metavar="path", default=None,
+                    help="DEPRECATED path for machine-readable result log.")
+
 
 def pytest_configure(config):
     resultlog = config.option.resultlog
@@ -18,13 +21,14 @@ def pytest_configure(config):
         dirname = os.path.dirname(os.path.abspath(resultlog))
         if not os.path.isdir(dirname):
             os.makedirs(dirname)
-        logfile = open(resultlog, 'w', 1) # line buffered
+        logfile = open(resultlog, 'w', 1)  # line buffered
         config._resultlog = ResultLog(config, logfile)
         config.pluginmanager.register(config._resultlog)
 
         from _pytest.deprecated import RESULT_LOG
         config.warn('C1', RESULT_LOG)
 
+
 def pytest_unconfigure(config):
     resultlog = getattr(config, '_resultlog', None)
     if resultlog:
@@ -32,6 +36,7 @@ def pytest_unconfigure(config):
         del config._resultlog
         config.pluginmanager.unregister(resultlog)
 
+
 def generic_path(item):
     chain = item.listchain()
     gpath = [chain[0].name]
@@ -55,15 +60,16 @@ def generic_path(item):
         fspath = newfspath
     return ''.join(gpath)
 
+
 class ResultLog(object):
     def __init__(self, config, logfile):
         self.config = config
-        self.logfile = logfile # preferably line buffered
+        self.logfile = logfile  # preferably line buffered
 
     def write_log_entry(self, testpath, lettercode, longrepr):
-        py.builtin.print_("%s %s" % (lettercode, testpath), file=self.logfile)
+        print("%s %s" % (lettercode, testpath), file=self.logfile)
         for line in longrepr.splitlines():
-            py.builtin.print_(" %s" % line, file=self.logfile)
+            print(" %s" % line, file=self.logfile)
 
     def log_outcome(self, report, lettercode, longrepr):
         testpath = getattr(report, 'nodeid', None)
diff --git a/lib/spack/external/_pytest/runner.py b/lib/spack/external/_pytest/runner.py
index eb29e7370c..b643fa3c91 100644
--- a/lib/spack/external/_pytest/runner.py
+++ b/lib/spack/external/_pytest/runner.py
@@ -1,29 +1,26 @@
 """ basic collect and runtest protocol implementations """
+from __future__ import absolute_import, division, print_function
+
 import bdb
+import os
 import sys
 from time import time
 
 import py
-import pytest
+from _pytest.compat import _PY2
 from _pytest._code.code import TerminalRepr, ExceptionInfo
-
-
-def pytest_namespace():
-    return {
-        'fail'         : fail,
-        'skip'         : skip,
-        'importorskip' : importorskip,
-        'exit'         : exit,
-    }
+from _pytest.outcomes import skip, Skipped, TEST_OUTCOME
 
 #
 # pytest plugin hooks
 
+
 def pytest_addoption(parser):
     group = parser.getgroup("terminal reporting", "reporting", after="general")
     group.addoption('--durations',
-         action="store", type=int, default=None, metavar="N",
-         help="show N slowest setup/test durations (N=0 for all)."),
+                    action="store", type=int, default=None, metavar="N",
+                    help="show N slowest setup/test durations (N=0 for all)."),
+
 
 def pytest_terminal_summary(terminalreporter):
     durations = terminalreporter.config.option.durations
@@ -48,16 +45,16 @@ def pytest_terminal_summary(terminalreporter):
     for rep in dlist:
         nodeid = rep.nodeid.replace("::()::", "::")
         tr.write_line("%02.2fs %-8s %s" %
-            (rep.duration, rep.when, nodeid))
+                      (rep.duration, rep.when, nodeid))
+
 
 def pytest_sessionstart(session):
     session._setupstate = SetupState()
+
+
 def pytest_sessionfinish(session):
     session._setupstate.teardown_all()
 
-class NodeInfo:
-    def __init__(self, location):
-        self.location = location
 
 def pytest_runtest_protocol(item, nextitem):
     item.ihook.pytest_runtest_logstart(
@@ -66,6 +63,7 @@ def pytest_runtest_protocol(item, nextitem):
     runtestprotocol(item, nextitem=nextitem)
     return True
 
+
 def runtestprotocol(item, log=True, nextitem=None):
     hasrequest = hasattr(item, "_request")
     if hasrequest and not item._request:
@@ -78,7 +76,7 @@ def runtestprotocol(item, log=True, nextitem=None):
         if not item.config.option.setuponly:
             reports.append(call_and_report(item, "call", log))
     reports.append(call_and_report(item, "teardown", log,
-        nextitem=nextitem))
+                                   nextitem=nextitem))
     # after all teardown hooks have been called
     # want funcargs and request info to go away
     if hasrequest:
@@ -86,6 +84,7 @@ def runtestprotocol(item, log=True, nextitem=None):
         item.funcargs = None
     return reports
 
+
 def show_test_item(item):
     """Show test function, parameters and the fixtures of the test item."""
     tw = item.config.get_terminal_writer()
@@ -96,10 +95,14 @@ def show_test_item(item):
     if used_fixtures:
         tw.write(' (fixtures used: {0})'.format(', '.join(used_fixtures)))
 
+
 def pytest_runtest_setup(item):
+    _update_current_test_var(item, 'setup')
     item.session._setupstate.prepare(item)
 
+
 def pytest_runtest_call(item):
+    _update_current_test_var(item, 'call')
     try:
         item.runtest()
     except Exception:
@@ -112,8 +115,29 @@ def pytest_runtest_call(item):
         del tb  # Get rid of it in this namespace
         raise
 
+
 def pytest_runtest_teardown(item, nextitem):
+    _update_current_test_var(item, 'teardown')
     item.session._setupstate.teardown_exact(item, nextitem)
+    _update_current_test_var(item, None)
+
+
+def _update_current_test_var(item, when):
+    """
+    Update PYTEST_CURRENT_TEST to reflect the current item and stage.
+
+    If ``when`` is None, delete PYTEST_CURRENT_TEST from the environment.
+    """
+    var_name = 'PYTEST_CURRENT_TEST'
+    if when:
+        value = '{0} ({1})'.format(item.nodeid, when)
+        if _PY2:
+            # python 2 doesn't like null bytes on environment variables (see #2644)
+            value = value.replace('\x00', '(null)')
+        os.environ[var_name] = value
+    else:
+        os.environ.pop(var_name)
+
 
 def pytest_report_teststatus(report):
     if report.when in ("setup", "teardown"):
@@ -139,21 +163,25 @@ def call_and_report(item, when, log=True, **kwds):
         hook.pytest_exception_interact(node=item, call=call, report=report)
     return report
 
+
 def check_interactive_exception(call, report):
     return call.excinfo and not (
-                hasattr(report, "wasxfail") or
-                call.excinfo.errisinstance(skip.Exception) or
-                call.excinfo.errisinstance(bdb.BdbQuit))
+        hasattr(report, "wasxfail") or
+        call.excinfo.errisinstance(skip.Exception) or
+        call.excinfo.errisinstance(bdb.BdbQuit))
+
 
 def call_runtest_hook(item, when, **kwds):
     hookname = "pytest_runtest_" + when
     ihook = getattr(item.ihook, hookname)
     return CallInfo(lambda: ihook(item=item, **kwds), when=when)
 
+
 class CallInfo:
     """ Result/Exception info a function invocation. """
     #: None or ExceptionInfo object.
     excinfo = None
+
     def __init__(self, func, when):
         #: context of invocation: one of "setup", "call",
         #: "teardown", "memocollect"
@@ -164,7 +192,7 @@ class CallInfo:
         except KeyboardInterrupt:
             self.stop = time()
             raise
-        except:
+        except:  # noqa
             self.excinfo = ExceptionInfo()
         self.stop = time()
 
@@ -175,6 +203,7 @@ class CallInfo:
             status = "result: %r" % (self.result,)
         return "<CallInfo when=%r %s>" % (self.when, status)
 
+
 def getslaveinfoline(node):
     try:
         return node._slaveinfocache
@@ -185,6 +214,7 @@ def getslaveinfoline(node):
             d['id'], d['sysplatform'], ver, d['executable'])
         return s
 
+
 class BaseReport(object):
 
     def __init__(self, **kw):
@@ -249,10 +279,11 @@ class BaseReport(object):
     def fspath(self):
         return self.nodeid.split("::")[0]
 
+
 def pytest_runtest_makereport(item, call):
     when = call.when
-    duration = call.stop-call.start
-    keywords = dict([(x,1) for x in item.keywords])
+    duration = call.stop - call.start
+    keywords = dict([(x, 1) for x in item.keywords])
     excinfo = call.excinfo
     sections = []
     if not call.excinfo:
@@ -262,7 +293,7 @@ def pytest_runtest_makereport(item, call):
         if not isinstance(excinfo, ExceptionInfo):
             outcome = "failed"
             longrepr = excinfo
-        elif excinfo.errisinstance(pytest.skip.Exception):
+        elif excinfo.errisinstance(skip.Exception):
             outcome = "skipped"
             r = excinfo._getreprcrash()
             longrepr = (str(r.path), r.lineno, r.message)
@@ -270,19 +301,21 @@ def pytest_runtest_makereport(item, call):
             outcome = "failed"
             if call.when == "call":
                 longrepr = item.repr_failure(excinfo)
-            else: # exception in setup or teardown
+            else:  # exception in setup or teardown
                 longrepr = item._repr_failure_py(excinfo,
-                                            style=item.config.option.tbstyle)
+                                                 style=item.config.option.tbstyle)
     for rwhen, key, content in item._report_sections:
-        sections.append(("Captured %s %s" %(key, rwhen), content))
+        sections.append(("Captured %s %s" % (key, rwhen), content))
     return TestReport(item.nodeid, item.location,
                       keywords, outcome, longrepr, when,
                       sections, duration)
 
+
 class TestReport(BaseReport):
     """ Basic test report object (also used for setup and teardown calls if
     they fail).
     """
+
     def __init__(self, nodeid, location, keywords, outcome,
                  longrepr, when, sections=(), duration=0, **extra):
         #: normalized collection node id
@@ -321,16 +354,21 @@ class TestReport(BaseReport):
         return "<TestReport %r when=%r outcome=%r>" % (
             self.nodeid, self.when, self.outcome)
 
+
 class TeardownErrorReport(BaseReport):
     outcome = "failed"
     when = "teardown"
+
     def __init__(self, longrepr, **extra):
         self.longrepr = longrepr
         self.sections = []
         self.__dict__.update(extra)
 
+
 def pytest_make_collect_report(collector):
-    call = CallInfo(collector._memocollect, "memocollect")
+    call = CallInfo(
+        lambda: list(collector.collect()),
+        'collect')
     longrepr = None
     if not call.excinfo:
         outcome = "passed"
@@ -348,7 +386,7 @@ def pytest_make_collect_report(collector):
                 errorinfo = CollectErrorRepr(errorinfo)
             longrepr = errorinfo
     rep = CollectReport(collector.nodeid, outcome, longrepr,
-        getattr(call, 'result', None))
+                        getattr(call, 'result', None))
     rep.call = call  # see collect_one_node
     return rep
 
@@ -369,16 +407,20 @@ class CollectReport(BaseReport):
 
     def __repr__(self):
         return "<CollectReport %r lenresult=%s outcome=%r>" % (
-                self.nodeid, len(self.result), self.outcome)
+            self.nodeid, len(self.result), self.outcome)
+
 
 class CollectErrorRepr(TerminalRepr):
     def __init__(self, msg):
         self.longrepr = msg
+
     def toterminal(self, out):
         out.line(self.longrepr, red=True)
 
+
 class SetupState(object):
     """ shared state for setting up/tearing down test items or collectors. """
+
     def __init__(self):
         self.stack = []
         self._finalizers = {}
@@ -390,7 +432,7 @@ class SetupState(object):
         """
         assert colitem and not isinstance(colitem, tuple)
         assert py.builtin.callable(finalizer)
-        #assert colitem in self.stack  # some unit tests don't setup stack :/
+        # assert colitem in self.stack  # some unit tests don't setup stack :/
         self._finalizers.setdefault(colitem, []).append(finalizer)
 
     def _pop_and_teardown(self):
@@ -404,7 +446,7 @@ class SetupState(object):
             fin = finalizers.pop()
             try:
                 fin()
-            except Exception:
+            except TEST_OUTCOME:
                 # XXX Only first exception will be seen by user,
                 #     ideally all should be reported.
                 if exc is None:
@@ -418,7 +460,7 @@ class SetupState(object):
             colitem.teardown()
         for colitem in self._finalizers:
             assert colitem is None or colitem in self.stack \
-             or isinstance(colitem, tuple)
+                or isinstance(colitem, tuple)
 
     def teardown_all(self):
         while self.stack:
@@ -451,10 +493,11 @@ class SetupState(object):
             self.stack.append(col)
             try:
                 col.setup()
-            except Exception:
+            except TEST_OUTCOME:
                 col._prepare_exc = sys.exc_info()
                 raise
 
+
 def collect_one_node(collector):
     ihook = collector.ihook
     ihook.pytest_collectstart(collector=collector)
@@ -463,116 +506,3 @@ def collect_one_node(collector):
     if call and check_interactive_exception(call, rep):
         ihook.pytest_exception_interact(node=collector, call=call, report=rep)
     return rep
-
-
-# =============================================================
-# Test OutcomeExceptions and helpers for creating them.
-
-
-class OutcomeException(Exception):
-    """ OutcomeException and its subclass instances indicate and
-        contain info about test and collection outcomes.
-    """
-    def __init__(self, msg=None, pytrace=True):
-        Exception.__init__(self, msg)
-        self.msg = msg
-        self.pytrace = pytrace
-
-    def __repr__(self):
-        if self.msg:
-            val = self.msg
-            if isinstance(val, bytes):
-                val = py._builtin._totext(val, errors='replace')
-            return val
-        return "<%s instance>" %(self.__class__.__name__,)
-    __str__ = __repr__
-
-class Skipped(OutcomeException):
-    # XXX hackish: on 3k we fake to live in the builtins
-    # in order to have Skipped exception printing shorter/nicer
-    __module__ = 'builtins'
-
-    def __init__(self, msg=None, pytrace=True, allow_module_level=False):
-        OutcomeException.__init__(self, msg=msg, pytrace=pytrace)
-        self.allow_module_level = allow_module_level
-
-
-class Failed(OutcomeException):
-    """ raised from an explicit call to pytest.fail() """
-    __module__ = 'builtins'
-
-
-class Exit(KeyboardInterrupt):
-    """ raised for immediate program exits (no tracebacks/summaries)"""
-    def __init__(self, msg="unknown reason"):
-        self.msg = msg
-        KeyboardInterrupt.__init__(self, msg)
-
-# exposed helper methods
-
-def exit(msg):
-    """ exit testing process as if KeyboardInterrupt was triggered. """
-    __tracebackhide__ = True
-    raise Exit(msg)
-
-
-exit.Exception = Exit
-
-
-def skip(msg=""):
-    """ skip an executing test with the given message.  Note: it's usually
-    better to use the pytest.mark.skipif marker to declare a test to be
-    skipped under certain conditions like mismatching platforms or
-    dependencies.  See the pytest_skipping plugin for details.
-    """
-    __tracebackhide__ = True
-    raise Skipped(msg=msg)
-
-
-skip.Exception = Skipped
-
-
-def fail(msg="", pytrace=True):
-    """ explicitly fail an currently-executing test with the given Message.
-
-    :arg pytrace: if false the msg represents the full failure information
-                  and no python traceback will be reported.
-    """
-    __tracebackhide__ = True
-    raise Failed(msg=msg, pytrace=pytrace)
-
-
-fail.Exception = Failed
-
-
-def importorskip(modname, minversion=None):
-    """ return imported module if it has at least "minversion" as its
-    __version__ attribute.  If no minversion is specified the a skip
-    is only triggered if the module can not be imported.
-    """
-    __tracebackhide__ = True
-    compile(modname, '', 'eval') # to catch syntaxerrors
-    should_skip = False
-    try:
-        __import__(modname)
-    except ImportError:
-        # Do not raise chained exception here(#1485)
-        should_skip = True
-    if should_skip:
-        raise Skipped("could not import %r" %(modname,), allow_module_level=True)
-    mod = sys.modules[modname]
-    if minversion is None:
-        return mod
-    verattr = getattr(mod, '__version__', None)
-    if minversion is not None:
-        try:
-            from pkg_resources import parse_version as pv
-        except ImportError:
-            raise Skipped("we have a required version for %r but can not import "
-                          "pkg_resources to parse version strings." % (modname,),
-                          allow_module_level=True)
-        if verattr is None or pv(verattr) < pv(minversion):
-            raise Skipped("module %r has __version__ %r, required is: %r" %(
-                          modname, verattr, minversion), allow_module_level=True)
-    return mod
-
diff --git a/lib/spack/external/_pytest/setuponly.py b/lib/spack/external/_pytest/setuponly.py
index 1752c575f5..15e195ad5a 100644
--- a/lib/spack/external/_pytest/setuponly.py
+++ b/lib/spack/external/_pytest/setuponly.py
@@ -1,3 +1,5 @@
+from __future__ import absolute_import, division, print_function
+
 import pytest
 import sys
 
diff --git a/lib/spack/external/_pytest/setupplan.py b/lib/spack/external/_pytest/setupplan.py
index f0853dee54..e11bd40698 100644
--- a/lib/spack/external/_pytest/setupplan.py
+++ b/lib/spack/external/_pytest/setupplan.py
@@ -1,3 +1,5 @@
+from __future__ import absolute_import, division, print_function
+
 import pytest
 
 
diff --git a/lib/spack/external/_pytest/skipping.py b/lib/spack/external/_pytest/skipping.py
index a8eaea98aa..b92800d10b 100644
--- a/lib/spack/external/_pytest/skipping.py
+++ b/lib/spack/external/_pytest/skipping.py
@@ -1,18 +1,21 @@
 """ support for skip/xfail functions and markers. """
+from __future__ import absolute_import, division, print_function
+
 import os
 import sys
 import traceback
 
 import py
-import pytest
+from _pytest.config import hookimpl
 from _pytest.mark import MarkInfo, MarkDecorator
+from _pytest.outcomes import fail, skip, xfail, TEST_OUTCOME
 
 
 def pytest_addoption(parser):
     group = parser.getgroup("general")
     group.addoption('--runxfail',
-           action="store_true", dest="runxfail", default=False,
-           help="run tests even if they are marked xfail")
+                    action="store_true", dest="runxfail", default=False,
+                    help="run tests even if they are marked xfail")
 
     parser.addini("xfail_strict", "default for the strict parameter of xfail "
                                   "markers when not given explicitly (default: "
@@ -23,53 +26,38 @@ def pytest_addoption(parser):
 
 def pytest_configure(config):
     if config.option.runxfail:
+        # yay a hack
+        import pytest
         old = pytest.xfail
         config._cleanup.append(lambda: setattr(pytest, "xfail", old))
 
         def nop(*args, **kwargs):
             pass
 
-        nop.Exception = XFailed
+        nop.Exception = xfail.Exception
         setattr(pytest, "xfail", nop)
 
     config.addinivalue_line("markers",
-        "skip(reason=None): skip the given test function with an optional reason. "
-        "Example: skip(reason=\"no way of currently testing this\") skips the "
-        "test."
-    )
+                            "skip(reason=None): skip the given test function with an optional reason. "
+                            "Example: skip(reason=\"no way of currently testing this\") skips the "
+                            "test."
+                            )
     config.addinivalue_line("markers",
-        "skipif(condition): skip the given test function if eval(condition) "
-        "results in a True value.  Evaluation happens within the "
-        "module global context. Example: skipif('sys.platform == \"win32\"') "
-        "skips the test if we are on the win32 platform. see "
-        "http://pytest.org/latest/skipping.html"
-    )
+                            "skipif(condition): skip the given test function if eval(condition) "
+                            "results in a True value.  Evaluation happens within the "
+                            "module global context. Example: skipif('sys.platform == \"win32\"') "
+                            "skips the test if we are on the win32 platform. see "
+                            "http://pytest.org/latest/skipping.html"
+                            )
     config.addinivalue_line("markers",
-        "xfail(condition, reason=None, run=True, raises=None, strict=False): "
-        "mark the the test function as an expected failure if eval(condition) "
-        "has a True value. Optionally specify a reason for better reporting "
-        "and run=False if you don't even want to execute the test function. "
-        "If only specific exception(s) are expected, you can list them in "
-        "raises, and if the test fails in other ways, it will be reported as "
-        "a true failure. See http://pytest.org/latest/skipping.html"
-    )
-
-
-def pytest_namespace():
-    return dict(xfail=xfail)
-
-
-class XFailed(pytest.fail.Exception):
-    """ raised from an explicit call to pytest.xfail() """
-
-
-def xfail(reason=""):
-    """ xfail an executing test or setup functions with the given reason."""
-    __tracebackhide__ = True
-    raise XFailed(reason)
-
-
-xfail.Exception = XFailed
+                            "xfail(condition, reason=None, run=True, raises=None, strict=False): "
+                            "mark the test function as an expected failure if eval(condition) "
+                            "has a True value. Optionally specify a reason for better reporting "
+                            "and run=False if you don't even want to execute the test function. "
+                            "If only specific exception(s) are expected, you can list them in "
+                            "raises, and if the test fails in other ways, it will be reported as "
+                            "a true failure. See http://pytest.org/latest/skipping.html"
+                            )
 
 
 class MarkEvaluator:
@@ -97,51 +85,50 @@ class MarkEvaluator:
     def istrue(self):
         try:
             return self._istrue()
-        except Exception:
+        except TEST_OUTCOME:
             self.exc = sys.exc_info()
             if isinstance(self.exc[1], SyntaxError):
-                msg = [" " * (self.exc[1].offset + 4) + "^",]
+                msg = [" " * (self.exc[1].offset + 4) + "^", ]
                 msg.append("SyntaxError: invalid syntax")
             else:
                 msg = traceback.format_exception_only(*self.exc[:2])
-            pytest.fail("Error evaluating %r expression\n"
-                        "    %s\n"
-                        "%s"
-                        %(self.name, self.expr, "\n".join(msg)),
-                        pytrace=False)
+            fail("Error evaluating %r expression\n"
+                 "    %s\n"
+                 "%s"
+                 % (self.name, self.expr, "\n".join(msg)),
+                 pytrace=False)
 
     def _getglobals(self):
         d = {'os': os, 'sys': sys, 'config': self.item.config}
-        d.update(self.item.obj.__globals__)
+        if hasattr(self.item, 'obj'):
+            d.update(self.item.obj.__globals__)
         return d
 
     def _istrue(self):
         if hasattr(self, 'result'):
             return self.result
         if self.holder:
-            d = self._getglobals()
             if self.holder.args or 'condition' in self.holder.kwargs:
                 self.result = False
                 # "holder" might be a MarkInfo or a MarkDecorator; only
                 # MarkInfo keeps track of all parameters it received in an
                 # _arglist attribute
-                if hasattr(self.holder, '_arglist'):
-                    arglist = self.holder._arglist
-                else:
-                    arglist = [(self.holder.args, self.holder.kwargs)]
-                for args, kwargs in arglist:
+                marks = getattr(self.holder, '_marks', None) \
+                    or [self.holder.mark]
+                for _, args, kwargs in marks:
                     if 'condition' in kwargs:
                         args = (kwargs['condition'],)
                     for expr in args:
                         self.expr = expr
                         if isinstance(expr, py.builtin._basestring):
+                            d = self._getglobals()
                             result = cached_eval(self.item.config, expr, d)
                         else:
                             if "reason" not in kwargs:
                                 # XXX better be checked at collection time
                                 msg = "you need to specify reason=STRING " \
                                       "when using booleans as conditions."
-                                pytest.fail(msg)
+                                fail(msg)
                             result = bool(expr)
                         if result:
                             self.result = True
@@ -165,7 +152,7 @@ class MarkEvaluator:
         return expl
 
 
-@pytest.hookimpl(tryfirst=True)
+@hookimpl(tryfirst=True)
 def pytest_runtest_setup(item):
     # Check if skip or skipif are specified as pytest marks
 
@@ -174,23 +161,23 @@ def pytest_runtest_setup(item):
         eval_skipif = MarkEvaluator(item, 'skipif')
         if eval_skipif.istrue():
             item._evalskip = eval_skipif
-            pytest.skip(eval_skipif.getexplanation())
+            skip(eval_skipif.getexplanation())
 
     skip_info = item.keywords.get('skip')
     if isinstance(skip_info, (MarkInfo, MarkDecorator)):
         item._evalskip = True
         if 'reason' in skip_info.kwargs:
-            pytest.skip(skip_info.kwargs['reason'])
+            skip(skip_info.kwargs['reason'])
         elif skip_info.args:
-            pytest.skip(skip_info.args[0])
+            skip(skip_info.args[0])
         else:
-            pytest.skip("unconditional skip")
+            skip("unconditional skip")
 
     item._evalxfail = MarkEvaluator(item, 'xfail')
     check_xfail_no_run(item)
 
 
-@pytest.mark.hookwrapper
+@hookimpl(hookwrapper=True)
 def pytest_pyfunc_call(pyfuncitem):
     check_xfail_no_run(pyfuncitem)
     outcome = yield
@@ -205,7 +192,7 @@ def check_xfail_no_run(item):
         evalxfail = item._evalxfail
         if evalxfail.istrue():
             if not evalxfail.get('run', True):
-                pytest.xfail("[NOTRUN] " + evalxfail.getexplanation())
+                xfail("[NOTRUN] " + evalxfail.getexplanation())
 
 
 def check_strict_xfail(pyfuncitem):
@@ -217,10 +204,10 @@ def check_strict_xfail(pyfuncitem):
         if is_strict_xfail:
             del pyfuncitem._evalxfail
             explanation = evalxfail.getexplanation()
-            pytest.fail('[XPASS(strict)] ' + explanation, pytrace=False)
+            fail('[XPASS(strict)] ' + explanation, pytrace=False)
 
 
-@pytest.hookimpl(hookwrapper=True)
+@hookimpl(hookwrapper=True)
 def pytest_runtest_makereport(item, call):
     outcome = yield
     rep = outcome.get_result()
@@ -240,11 +227,11 @@ def pytest_runtest_makereport(item, call):
             rep.wasxfail = rep.longrepr
     elif item.config.option.runxfail:
         pass   # don't interefere
-    elif call.excinfo and call.excinfo.errisinstance(pytest.xfail.Exception):
+    elif call.excinfo and call.excinfo.errisinstance(xfail.Exception):
         rep.wasxfail = "reason: " + call.excinfo.value.msg
         rep.outcome = "skipped"
     elif evalxfail and not rep.skipped and evalxfail.wasvalid() and \
-        evalxfail.istrue():
+            evalxfail.istrue():
         if call.excinfo:
             if evalxfail.invalidraise(call.excinfo.value):
                 rep.outcome = "failed"
@@ -270,6 +257,8 @@ def pytest_runtest_makereport(item, call):
         rep.longrepr = filename, line, reason
 
 # called by terminalreporter progress reporting
+
+
 def pytest_report_teststatus(report):
     if hasattr(report, "wasxfail"):
         if report.skipped:
@@ -278,10 +267,12 @@ def pytest_report_teststatus(report):
             return "xpassed", "X", ("XPASS", {'yellow': True})
 
 # called by the terminalreporter instance/plugin
+
+
 def pytest_terminal_summary(terminalreporter):
     tr = terminalreporter
     if not tr.reportchars:
-        #for name in "xfailed skipped failed xpassed":
+        # for name in "xfailed skipped failed xpassed":
         #    if not tr.stats.get(name, 0):
         #        tr.write_line("HINT: use '-r' option to see extra "
         #              "summary info about tests")
@@ -308,12 +299,14 @@ def pytest_terminal_summary(terminalreporter):
         for line in lines:
             tr._tw.line(line)
 
+
 def show_simple(terminalreporter, lines, stat, format):
     failed = terminalreporter.stats.get(stat)
     if failed:
         for rep in failed:
             pos = terminalreporter.config.cwd_relative_nodeid(rep.nodeid)
-            lines.append(format %(pos,))
+            lines.append(format % (pos,))
+
 
 def show_xfailed(terminalreporter, lines):
     xfailed = terminalreporter.stats.get("xfailed")
@@ -325,13 +318,15 @@ def show_xfailed(terminalreporter, lines):
             if reason:
                 lines.append("  " + str(reason))
 
+
 def show_xpassed(terminalreporter, lines):
     xpassed = terminalreporter.stats.get("xpassed")
     if xpassed:
         for rep in xpassed:
             pos = terminalreporter.config.cwd_relative_nodeid(rep.nodeid)
             reason = rep.wasxfail
-            lines.append("XPASS %s %s" %(pos, reason))
+            lines.append("XPASS %s %s" % (pos, reason))
+
 
 def cached_eval(config, expr, d):
     if not hasattr(config, '_evalcache'):
@@ -351,25 +346,27 @@ def folded_skips(skipped):
         key = event.longrepr
         assert len(key) == 3, (event, key)
         d.setdefault(key, []).append(event)
-    l = []
+    values = []
     for key, events in d.items():
-        l.append((len(events),) + key)
-    return l
+        values.append((len(events),) + key)
+    return values
+
 
 def show_skipped(terminalreporter, lines):
     tr = terminalreporter
     skipped = tr.stats.get('skipped', [])
     if skipped:
-        #if not tr.hasopt('skipped'):
+        # if not tr.hasopt('skipped'):
         #    tr.write_line(
         #        "%d skipped tests, specify -rs for more info" %
         #        len(skipped))
         #    return
         fskips = folded_skips(skipped)
         if fskips:
-            #tr.write_sep("_", "skipped test summary")
+            # tr.write_sep("_", "skipped test summary")
             for num, fspath, lineno, reason in fskips:
                 if reason.startswith("Skipped: "):
                     reason = reason[9:]
-                lines.append("SKIP [%d] %s:%d: %s" %
-                    (num, fspath, lineno, reason))
+                lines.append(
+                    "SKIP [%d] %s:%d: %s" %
+                    (num, fspath, lineno + 1, reason))
diff --git a/lib/spack/external/_pytest/terminal.py b/lib/spack/external/_pytest/terminal.py
index 16bf757338..9da94d0c91 100644
--- a/lib/spack/external/_pytest/terminal.py
+++ b/lib/spack/external/_pytest/terminal.py
@@ -2,6 +2,9 @@
 
 This is a good source for looking at the various reporting hooks.
 """
+from __future__ import absolute_import, division, print_function
+
+import itertools
 from _pytest.main import EXIT_OK, EXIT_TESTSFAILED, EXIT_INTERRUPTED, \
     EXIT_USAGEERROR, EXIT_NOTESTSCOLLECTED
 import pytest
@@ -10,39 +13,41 @@ import sys
 import time
 import platform
 
+from _pytest import nodes
 import _pytest._pluggy as pluggy
 
 
 def pytest_addoption(parser):
     group = parser.getgroup("terminal reporting", "reporting", after="general")
     group._addoption('-v', '--verbose', action="count",
-               dest="verbose", default=0, help="increase verbosity."),
+                     dest="verbose", default=0, help="increase verbosity."),
     group._addoption('-q', '--quiet', action="count",
-               dest="quiet", default=0, help="decrease verbosity."),
+                     dest="quiet", default=0, help="decrease verbosity."),
     group._addoption('-r',
-         action="store", dest="reportchars", default='', metavar="chars",
-         help="show extra test summary info as specified by chars (f)ailed, "
-              "(E)error, (s)skipped, (x)failed, (X)passed, "
-              "(p)passed, (P)passed with output, (a)all except pP. "
-              "The pytest warnings are displayed at all times except when "
-              "--disable-pytest-warnings is set")
-    group._addoption('--disable-pytest-warnings', default=False,
-                     dest='disablepytestwarnings', action='store_true',
-                     help='disable warnings summary, overrides -r w flag')
+                     action="store", dest="reportchars", default='', metavar="chars",
+                     help="show extra test summary info as specified by chars (f)ailed, "
+                     "(E)error, (s)skipped, (x)failed, (X)passed, "
+                     "(p)passed, (P)passed with output, (a)all except pP. "
+                     "Warnings are displayed at all times except when "
+                     "--disable-warnings is set")
+    group._addoption('--disable-warnings', '--disable-pytest-warnings', default=False,
+                     dest='disable_warnings', action='store_true',
+                     help='disable warnings summary')
     group._addoption('-l', '--showlocals',
-         action="store_true", dest="showlocals", default=False,
-         help="show locals in tracebacks (disabled by default).")
+                     action="store_true", dest="showlocals", default=False,
+                     help="show locals in tracebacks (disabled by default).")
     group._addoption('--tb', metavar="style",
-               action="store", dest="tbstyle", default='auto',
-               choices=['auto', 'long', 'short', 'no', 'line', 'native'],
-               help="traceback print mode (auto/long/short/line/native/no).")
+                     action="store", dest="tbstyle", default='auto',
+                     choices=['auto', 'long', 'short', 'no', 'line', 'native'],
+                     help="traceback print mode (auto/long/short/line/native/no).")
     group._addoption('--fulltrace', '--full-trace',
-               action="store_true", default=False,
-               help="don't cut any tracebacks (default is to cut).")
+                     action="store_true", default=False,
+                     help="don't cut any tracebacks (default is to cut).")
     group._addoption('--color', metavar="color",
-               action="store", dest="color", default='auto',
-               choices=['yes', 'no', 'auto'],
-               help="color terminal output (yes/no/auto).")
+                     action="store", dest="color", default='auto',
+                     choices=['yes', 'no', 'auto'],
+                     help="color terminal output (yes/no/auto).")
+
 
 def pytest_configure(config):
     config.option.verbose -= config.option.quiet
@@ -54,12 +59,13 @@ def pytest_configure(config):
             reporter.write_line("[traceconfig] " + msg)
         config.trace.root.setprocessor("pytest:config", mywriter)
 
+
 def getreportopt(config):
     reportopts = ""
     reportchars = config.option.reportchars
-    if not config.option.disablepytestwarnings and 'w' not in reportchars:
+    if not config.option.disable_warnings and 'w' not in reportchars:
         reportchars += 'w'
-    elif config.option.disablepytestwarnings and 'w' in reportchars:
+    elif config.option.disable_warnings and 'w' in reportchars:
         reportchars = reportchars.replace('w', '')
     if reportchars:
         for char in reportchars:
@@ -69,6 +75,7 @@ def getreportopt(config):
                 reportopts = 'fEsxXw'
     return reportopts
 
+
 def pytest_report_teststatus(report):
     if report.passed:
         letter = "."
@@ -80,13 +87,41 @@ def pytest_report_teststatus(report):
             letter = "f"
     return report.outcome, letter, report.outcome.upper()
 
+
 class WarningReport:
+    """
+    Simple structure to hold warnings information captured by ``pytest_logwarning``.
+    """
+
     def __init__(self, code, message, nodeid=None, fslocation=None):
+        """
+        :param code: unused
+        :param str message: user friendly message about the warning
+        :param str|None nodeid: node id that generated the warning (see ``get_location``).
+        :param tuple|py.path.local fslocation:
+            file system location of the source of the warning (see ``get_location``).
+        """
         self.code = code
         self.message = message
         self.nodeid = nodeid
         self.fslocation = fslocation
 
+    def get_location(self, config):
+        """
+        Returns the more user-friendly information about the location
+        of a warning, or None.
+        """
+        if self.nodeid:
+            return self.nodeid
+        if self.fslocation:
+            if isinstance(self.fslocation, tuple) and len(self.fslocation) >= 2:
+                filename, linenum = self.fslocation[:2]
+                relpath = py.path.local(filename).relto(config.invocation_dir)
+                return '%s:%s' % (relpath, linenum)
+            else:
+                return str(self.fslocation)
+        return None
+
 
 class TerminalReporter:
     def __init__(self, config, file=None):
@@ -146,8 +181,22 @@ class TerminalReporter:
         self._tw.line(line, **markup)
 
     def rewrite(self, line, **markup):
+        """
+        Rewinds the terminal cursor to the beginning and writes the given line.
+
+        :kwarg erase: if True, will also add spaces until the full terminal width to ensure
+            previous lines are properly erased.
+
+        The rest of the keyword arguments are markup instructions.
+        """
+        erase = markup.pop('erase', False)
+        if erase:
+            fill_count = self._tw.fullwidth - len(line)
+            fill = ' ' * fill_count
+        else:
+            fill = ''
         line = str(line)
-        self._tw.write("\r" + line, **markup)
+        self._tw.write("\r" + line + fill, **markup)
 
     def write_sep(self, sep, title=None, **markup):
         self.ensure_newline()
@@ -166,8 +215,6 @@ class TerminalReporter:
 
     def pytest_logwarning(self, code, fslocation, message, nodeid):
         warnings = self.stats.setdefault("warnings", [])
-        if isinstance(fslocation, tuple):
-            fslocation = "%s:%d" % fslocation
         warning = WarningReport(code=code, fslocation=fslocation,
                                 message=message, nodeid=nodeid)
         warnings.append(warning)
@@ -212,15 +259,15 @@ class TerminalReporter:
                 word, markup = word
             else:
                 if rep.passed:
-                    markup = {'green':True}
+                    markup = {'green': True}
                 elif rep.failed:
-                    markup = {'red':True}
+                    markup = {'red': True}
                 elif rep.skipped:
-                    markup = {'yellow':True}
+                    markup = {'yellow': True}
             line = self._locationline(rep.nodeid, *rep.location)
             if not hasattr(rep, 'node'):
                 self.write_ensure_prefix(line, word, **markup)
-                #self._tw.write(word, **markup)
+                # self._tw.write(word, **markup)
             else:
                 self.ensure_newline()
                 if hasattr(rep, 'node'):
@@ -241,7 +288,7 @@ class TerminalReporter:
         items = [x for x in report.result if isinstance(x, pytest.Item)]
         self._numcollected += len(items)
         if self.isatty:
-            #self.write_fspath_result(report.nodeid, 'E')
+            # self.write_fspath_result(report.nodeid, 'E')
             self.report_collect()
 
     def report_collect(self, final=False):
@@ -254,15 +301,15 @@ class TerminalReporter:
             line = "collected "
         else:
             line = "collecting "
-        line += str(self._numcollected) + " items"
+        line += str(self._numcollected) + " item" + ('' if self._numcollected == 1 else 's')
         if errors:
             line += " / %d errors" % errors
         if skipped:
             line += " / %d skipped" % skipped
         if self.isatty:
+            self.rewrite(line, bold=True, erase=True)
             if final:
-                line += " \n"
-            self.rewrite(line, bold=True)
+                self.write('\n')
         else:
             self.write_line(line)
 
@@ -288,6 +335,9 @@ class TerminalReporter:
         self.write_line(msg)
         lines = self.config.hook.pytest_report_header(
             config=self.config, startdir=self.startdir)
+        self._write_report_lines_from_hooks(lines)
+
+    def _write_report_lines_from_hooks(self, lines):
         lines.reverse()
         for line in flatten(lines):
             self.write_line(line)
@@ -295,8 +345,8 @@ class TerminalReporter:
     def pytest_report_header(self, config):
         inifile = ""
         if config.inifile:
-            inifile = config.rootdir.bestrelpath(config.inifile)
-        lines = ["rootdir: %s, inifile: %s" %(config.rootdir, inifile)]
+            inifile = " " + config.rootdir.bestrelpath(config.inifile)
+        lines = ["rootdir: %s, inifile:%s" % (config.rootdir, inifile)]
 
         plugininfo = config.pluginmanager.list_plugin_distinfo()
         if plugininfo:
@@ -314,10 +364,9 @@ class TerminalReporter:
                     rep.toterminal(self._tw)
                 return 1
             return 0
-        if not self.showheader:
-            return
-        #for i, testarg in enumerate(self.config.args):
-        #    self.write_line("test path %d: %s" %(i+1, testarg))
+        lines = self.config.hook.pytest_report_collectionfinish(
+            config=self.config, startdir=self.startdir, items=session.items)
+        self._write_report_lines_from_hooks(lines)
 
     def _printcollecteditems(self, items):
         # to print out items and their parent collectors
@@ -340,14 +389,14 @@ class TerminalReporter:
         stack = []
         indent = ""
         for item in items:
-            needed_collectors = item.listchain()[1:] # strip root node
+            needed_collectors = item.listchain()[1:]  # strip root node
             while stack:
                 if stack == needed_collectors[:len(stack)]:
                     break
                 stack.pop()
             for col in needed_collectors[len(stack):]:
                 stack.append(col)
-                #if col.name == "()":
+                # if col.name == "()":
                 #    continue
                 indent = (len(stack) - 1) * "  "
                 self._tw.line("%s%s" % (indent, col))
@@ -396,15 +445,15 @@ class TerminalReporter:
             line = self.config.cwd_relative_nodeid(nodeid)
             if domain and line.endswith(domain):
                 line = line[:-len(domain)]
-                l = domain.split("[")
-                l[0] = l[0].replace('.', '::')  # don't replace '.' in params
-                line += "[".join(l)
+                values = domain.split("[")
+                values[0] = values[0].replace('.', '::')  # don't replace '.' in params
+                line += "[".join(values)
             return line
         # collect_fspath comes from testid which has a "/"-normalized path
 
         if fspath:
             res = mkrel(nodeid).replace("::()", "")  # parens-normalization
-            if nodeid.split("::")[0] != fspath.replace("\\", "/"):
+            if nodeid.split("::")[0] != fspath.replace("\\", nodes.SEP):
                 res += " <- " + self.startdir.bestrelpath(fspath)
         else:
             res = "[location]"
@@ -415,7 +464,7 @@ class TerminalReporter:
             fspath, lineno, domain = rep.location
             return domain
         else:
-            return "test session" # XXX?
+            return "test session"  # XXX?
 
     def _getcrashline(self, rep):
         try:
@@ -430,21 +479,29 @@ class TerminalReporter:
     # summaries for sessionfinish
     #
     def getreports(self, name):
-        l = []
+        values = []
         for x in self.stats.get(name, []):
             if not hasattr(x, '_pdbshown'):
-                l.append(x)
-        return l
+                values.append(x)
+        return values
 
     def summary_warnings(self):
         if self.hasopt("w"):
-            warnings = self.stats.get("warnings")
-            if not warnings:
+            all_warnings = self.stats.get("warnings")
+            if not all_warnings:
                 return
-            self.write_sep("=", "pytest-warning summary")
-            for w in warnings:
-                self._tw.line("W%s %s %s" % (w.code,
-                              w.fslocation, w.message))
+
+            grouped = itertools.groupby(all_warnings, key=lambda wr: wr.get_location(self.config))
+
+            self.write_sep("=", "warnings summary", yellow=True, bold=False)
+            for location, warnings in grouped:
+                self._tw.line(str(location) or '<undetermined location>')
+                for w in warnings:
+                    lines = w.message.splitlines()
+                    indented = '\n'.join('  ' + x for x in lines)
+                    self._tw.line(indented)
+                self._tw.line()
+            self._tw.line('-- Docs: http://doc.pytest.org/en/latest/warnings.html')
 
     def summary_passes(self):
         if self.config.option.tbstyle != "no":
@@ -466,7 +523,6 @@ class TerminalReporter:
                     content = content[:-1]
                 self._tw.line(content)
 
-
     def summary_failures(self):
         if self.config.option.tbstyle != "no":
             reports = self.getreports('failed')
@@ -528,6 +584,7 @@ class TerminalReporter:
             self.write_sep("=", "%d tests deselected" % (
                 len(self.stats['deselected'])), bold=True)
 
+
 def repr_pythonversion(v=None):
     if v is None:
         v = sys.version_info
@@ -536,30 +593,30 @@ def repr_pythonversion(v=None):
     except (TypeError, ValueError):
         return str(v)
 
-def flatten(l):
-    for x in l:
+
+def flatten(values):
+    for x in values:
         if isinstance(x, (list, tuple)):
             for y in flatten(x):
                 yield y
         else:
             yield x
 
+
 def build_summary_stats_line(stats):
     keys = ("failed passed skipped deselected "
-           "xfailed xpassed warnings error").split()
-    key_translation = {'warnings': 'pytest-warnings'}
+            "xfailed xpassed warnings error").split()
     unknown_key_seen = False
     for key in stats.keys():
         if key not in keys:
-            if key: # setup/teardown reports have an empty key, ignore them
+            if key:  # setup/teardown reports have an empty key, ignore them
                 keys.append(key)
                 unknown_key_seen = True
     parts = []
     for key in keys:
         val = stats.get(key, None)
         if val:
-            key_name = key_translation.get(key, key)
-            parts.append("%d %s" % (len(val), key_name))
+            parts.append("%d %s" % (len(val), key))
 
     if parts:
         line = ", ".join(parts)
@@ -579,7 +636,7 @@ def build_summary_stats_line(stats):
 
 
 def _plugin_nameversions(plugininfo):
-    l = []
+    values = []
     for plugin, dist in plugininfo:
         # gets us name and version!
         name = '{dist.project_name}-{dist.version}'.format(dist=dist)
@@ -588,6 +645,6 @@ def _plugin_nameversions(plugininfo):
             name = name[7:]
         # we decided to print python package names
         # they can have more than one plugin
-        if name not in l:
-            l.append(name)
-    return l
+        if name not in values:
+            values.append(name)
+    return values
diff --git a/lib/spack/external/_pytest/tmpdir.py b/lib/spack/external/_pytest/tmpdir.py
index 28a6b06366..da1b032237 100644
--- a/lib/spack/external/_pytest/tmpdir.py
+++ b/lib/spack/external/_pytest/tmpdir.py
@@ -1,4 +1,6 @@
 """ support for providing temporary directories to test functions.  """
+from __future__ import absolute_import, division, print_function
+
 import re
 
 import pytest
@@ -23,7 +25,7 @@ class TempdirFactory:
             provides an empty unique-per-test-invocation directory
             and is guaranteed to be empty.
         """
-        #py.log._apiwarn(">1.1", "use tmpdir function argument")
+        # py.log._apiwarn(">1.1", "use tmpdir function argument")
         return self.getbasetemp().ensure(string, dir=dir)
 
     def mktemp(self, basename, numbered=True):
@@ -36,7 +38,7 @@ class TempdirFactory:
             p = basetemp.mkdir(basename)
         else:
             p = py.path.local.make_numbered_dir(prefix=basename,
-                keep=0, rootdir=basetemp, lock_timeout=None)
+                                                keep=0, rootdir=basetemp, lock_timeout=None)
         self.trace("mktemp", p)
         return p
 
@@ -116,7 +118,7 @@ def tmpdir(request, tmpdir_factory):
     path object.
     """
     name = request.node.name
-    name = re.sub("[\W]", "_", name)
+    name = re.sub(r"[\W]", "_", name)
     MAXVAL = 30
     if len(name) > MAXVAL:
         name = name[:MAXVAL]
diff --git a/lib/spack/external/_pytest/unittest.py b/lib/spack/external/_pytest/unittest.py
index 73224010b2..52c9813e8b 100644
--- a/lib/spack/external/_pytest/unittest.py
+++ b/lib/spack/external/_pytest/unittest.py
@@ -1,13 +1,14 @@
 """ discovery and running of std-library "unittest" style tests. """
-from __future__ import absolute_import
+from __future__ import absolute_import, division, print_function
 
 import sys
 import traceback
 
-import pytest
-# for transfering markers
+# for transferring markers
 import _pytest._code
-from _pytest.python import transfer_markers
+from _pytest.config import hookimpl
+from _pytest.outcomes import fail, skip, xfail
+from _pytest.python import transfer_markers, Class, Module, Function
 from _pytest.skipping import MarkEvaluator
 
 
@@ -22,11 +23,11 @@ def pytest_pycollect_makeitem(collector, name, obj):
     return UnitTestCase(name, parent=collector)
 
 
-class UnitTestCase(pytest.Class):
+class UnitTestCase(Class):
     # marker for fixturemanger.getfixtureinfo()
     # to declare that our children do not support funcargs
     nofuncargs = True
-                                              
+
     def setup(self):
         cls = self.obj
         if getattr(cls, '__unittest_skip__', False):
@@ -46,7 +47,7 @@ class UnitTestCase(pytest.Class):
             return
         self.session._fixturemanager.parsefactories(self, unittest=True)
         loader = TestLoader()
-        module = self.getparent(pytest.Module).obj
+        module = self.getparent(Module).obj
         foundsomething = False
         for name in loader.getTestCaseNames(self.obj):
             x = getattr(self.obj, name)
@@ -65,8 +66,7 @@ class UnitTestCase(pytest.Class):
                     yield TestCaseFunction('runTest', parent=self)
 
 
-
-class TestCaseFunction(pytest.Function):
+class TestCaseFunction(Function):
     _excinfo = None
 
     def setup(self):
@@ -109,38 +109,39 @@ class TestCaseFunction(pytest.Function):
         except TypeError:
             try:
                 try:
-                    l = traceback.format_exception(*rawexcinfo)
-                    l.insert(0, "NOTE: Incompatible Exception Representation, "
-                        "displaying natively:\n\n")
-                    pytest.fail("".join(l), pytrace=False)
-                except (pytest.fail.Exception, KeyboardInterrupt):
+                    values = traceback.format_exception(*rawexcinfo)
+                    values.insert(0, "NOTE: Incompatible Exception Representation, "
+                                  "displaying natively:\n\n")
+                    fail("".join(values), pytrace=False)
+                except (fail.Exception, KeyboardInterrupt):
                     raise
-                except:
-                    pytest.fail("ERROR: Unknown Incompatible Exception "
-                        "representation:\n%r" %(rawexcinfo,), pytrace=False)
+                except:  # noqa
+                    fail("ERROR: Unknown Incompatible Exception "
+                         "representation:\n%r" % (rawexcinfo,), pytrace=False)
             except KeyboardInterrupt:
                 raise
-            except pytest.fail.Exception:
+            except fail.Exception:
                 excinfo = _pytest._code.ExceptionInfo()
         self.__dict__.setdefault('_excinfo', []).append(excinfo)
 
     def addError(self, testcase, rawexcinfo):
         self._addexcinfo(rawexcinfo)
+
     def addFailure(self, testcase, rawexcinfo):
         self._addexcinfo(rawexcinfo)
 
     def addSkip(self, testcase, reason):
         try:
-            pytest.skip(reason)
-        except pytest.skip.Exception:
+            skip(reason)
+        except skip.Exception:
             self._evalskip = MarkEvaluator(self, 'SkipTest')
             self._evalskip.result = True
             self._addexcinfo(sys.exc_info())
 
     def addExpectedFailure(self, testcase, rawexcinfo, reason=""):
         try:
-            pytest.xfail(str(reason))
-        except pytest.xfail.Exception:
+            xfail(str(reason))
+        except xfail.Exception:
             self._addexcinfo(sys.exc_info())
 
     def addUnexpectedSuccess(self, testcase, reason=""):
@@ -152,22 +153,42 @@ class TestCaseFunction(pytest.Function):
     def stopTest(self, testcase):
         pass
 
+    def _handle_skip(self):
+        # implements the skipping machinery (see #2137)
+        # analog to pythons Lib/unittest/case.py:run
+        testMethod = getattr(self._testcase, self._testcase._testMethodName)
+        if (getattr(self._testcase.__class__, "__unittest_skip__", False) or
+                getattr(testMethod, "__unittest_skip__", False)):
+            # If the class or method was skipped.
+            skip_why = (getattr(self._testcase.__class__, '__unittest_skip_why__', '') or
+                        getattr(testMethod, '__unittest_skip_why__', ''))
+            try:  # PY3, unittest2 on PY2
+                self._testcase._addSkip(self, self._testcase, skip_why)
+            except TypeError:  # PY2
+                if sys.version_info[0] != 2:
+                    raise
+                self._testcase._addSkip(self, skip_why)
+            return True
+        return False
+
     def runtest(self):
         if self.config.pluginmanager.get_plugin("pdbinvoke") is None:
             self._testcase(result=self)
         else:
             # disables tearDown and cleanups for post mortem debugging (see #1890)
+            if self._handle_skip():
+                return
             self._testcase.debug()
 
-
     def _prunetraceback(self, excinfo):
-        pytest.Function._prunetraceback(self, excinfo)
+        Function._prunetraceback(self, excinfo)
         traceback = excinfo.traceback.filter(
-            lambda x:not x.frame.f_globals.get('__unittest'))
+            lambda x: not x.frame.f_globals.get('__unittest'))
         if traceback:
             excinfo.traceback = traceback
 
-@pytest.hookimpl(tryfirst=True)
+
+@hookimpl(tryfirst=True)
 def pytest_runtest_makereport(item, call):
     if isinstance(item, TestCaseFunction):
         if item._excinfo:
@@ -179,7 +200,8 @@ def pytest_runtest_makereport(item, call):
 
 # twisted trial support
 
-@pytest.hookimpl(hookwrapper=True)
+
+@hookimpl(hookwrapper=True)
 def pytest_runtest_protocol(item):
     if isinstance(item, TestCaseFunction) and \
        'twisted.trial.unittest' in sys.modules:
@@ -188,7 +210,7 @@ def pytest_runtest_protocol(item):
         check_testcase_implements_trial_reporter()
 
         def excstore(self, exc_value=None, exc_type=None, exc_tb=None,
-            captureVars=None):
+                     captureVars=None):
             if exc_value is None:
                 self._rawexcinfo = sys.exc_info()
             else:
@@ -197,7 +219,7 @@ def pytest_runtest_protocol(item):
                 self._rawexcinfo = (exc_type, exc_value, exc_tb)
             try:
                 Failure__init__(self, exc_value, exc_type, exc_tb,
-                    captureVars=captureVars)
+                                captureVars=captureVars)
             except TypeError:
                 Failure__init__(self, exc_value, exc_type, exc_tb)
 
diff --git a/lib/spack/external/_pytest/vendored_packages/pluggy.py b/lib/spack/external/_pytest/vendored_packages/pluggy.py
index 9c13932b36..aebddad01d 100644
--- a/lib/spack/external/_pytest/vendored_packages/pluggy.py
+++ b/lib/spack/external/_pytest/vendored_packages/pluggy.py
@@ -540,7 +540,7 @@ class PluginManager(object):
         of HookImpl instances and the keyword arguments for the hook call.
 
         ``after(outcome, hook_name, hook_impls, kwargs)`` receives the
-        same arguments as ``before`` but also a :py:class:`_CallOutcome`` object
+        same arguments as ``before`` but also a :py:class:`_CallOutcome <_pytest.vendored_packages.pluggy._CallOutcome>` object
         which represents the result of the overall hook call.
         """
         return _TracedHookExecution(self, before, after).undo
diff --git a/lib/spack/external/_pytest/warnings.py b/lib/spack/external/_pytest/warnings.py
new file mode 100644
index 0000000000..926b1f5811
--- /dev/null
+++ b/lib/spack/external/_pytest/warnings.py
@@ -0,0 +1,94 @@
+from __future__ import absolute_import, division, print_function
+
+import warnings
+from contextlib import contextmanager
+
+import pytest
+
+from _pytest import compat
+
+
+def _setoption(wmod, arg):
+    """
+    Copy of the warning._setoption function but does not escape arguments.
+    """
+    parts = arg.split(':')
+    if len(parts) > 5:
+        raise wmod._OptionError("too many fields (max 5): %r" % (arg,))
+    while len(parts) < 5:
+        parts.append('')
+    action, message, category, module, lineno = [s.strip()
+                                                 for s in parts]
+    action = wmod._getaction(action)
+    category = wmod._getcategory(category)
+    if lineno:
+        try:
+            lineno = int(lineno)
+            if lineno < 0:
+                raise ValueError
+        except (ValueError, OverflowError):
+            raise wmod._OptionError("invalid lineno %r" % (lineno,))
+    else:
+        lineno = 0
+    wmod.filterwarnings(action, message, category, module, lineno)
+
+
+def pytest_addoption(parser):
+    group = parser.getgroup("pytest-warnings")
+    group.addoption(
+        '-W', '--pythonwarnings', action='append',
+        help="set which warnings to report, see -W option of python itself.")
+    parser.addini("filterwarnings", type="linelist",
+                  help="Each line specifies a pattern for "
+                  "warnings.filterwarnings. "
+                  "Processed after -W and --pythonwarnings.")
+
+
+@contextmanager
+def catch_warnings_for_item(item):
+    """
+    catches the warnings generated during setup/call/teardown execution
+    of the given item and after it is done posts them as warnings to this
+    item.
+    """
+    args = item.config.getoption('pythonwarnings') or []
+    inifilters = item.config.getini("filterwarnings")
+    with warnings.catch_warnings(record=True) as log:
+        for arg in args:
+            warnings._setoption(arg)
+
+        for arg in inifilters:
+            _setoption(warnings, arg)
+
+        mark = item.get_marker('filterwarnings')
+        if mark:
+            for arg in mark.args:
+                warnings._setoption(arg)
+
+        yield
+
+        for warning in log:
+            warn_msg = warning.message
+            unicode_warning = False
+
+            if compat._PY2 and any(isinstance(m, compat.UNICODE_TYPES) for m in warn_msg.args):
+                new_args = [compat.safe_str(m) for m in warn_msg.args]
+                unicode_warning = warn_msg.args != new_args
+                warn_msg.args = new_args
+
+            msg = warnings.formatwarning(
+                warn_msg, warning.category,
+                warning.filename, warning.lineno, warning.line)
+            item.warn("unused", msg)
+
+            if unicode_warning:
+                warnings.warn(
+                    "Warning is using unicode non convertible to ascii, "
+                    "converting to a safe representation:\n  %s" % msg,
+                    UnicodeWarning)
+
+
+@pytest.hookimpl(hookwrapper=True)
+def pytest_runtest_protocol(item):
+    with catch_warnings_for_item(item):
+        yield
diff --git a/lib/spack/external/pytest.py b/lib/spack/external/pytest.py
index e376e417e8..1c914a6edf 100644
--- a/lib/spack/external/pytest.py
+++ b/lib/spack/external/pytest.py
@@ -2,6 +2,32 @@
 """
 pytest: unit and functional testing with Python.
 """
+
+
+# else we are imported
+
+from _pytest.config import (
+    main, UsageError, _preloadplugins, cmdline,
+    hookspec, hookimpl
+)
+from _pytest.fixtures import fixture, yield_fixture
+from _pytest.assertion import register_assert_rewrite
+from _pytest.freeze_support import freeze_includes
+from _pytest import __version__
+from _pytest.debugging import pytestPDB as __pytestPDB
+from _pytest.recwarn import warns, deprecated_call
+from _pytest.outcomes import fail, skip, importorskip, exit, xfail
+from _pytest.mark import MARK_GEN as mark, param
+from _pytest.main import Item, Collector, File, Session
+from _pytest.fixtures import fillfixtures as _fillfuncargs
+from _pytest.python import (
+    Module, Class, Instance, Function, Generator,
+)
+
+from _pytest.python_api import approx, raises
+
+set_trace = __pytestPDB.set_trace
+
 __all__ = [
     'main',
     'UsageError',
@@ -9,20 +35,44 @@ __all__ = [
     'hookspec',
     'hookimpl',
     '__version__',
+    'register_assert_rewrite',
+    'freeze_includes',
+    'set_trace',
+    'warns',
+    'deprecated_call',
+    'fixture',
+    'yield_fixture',
+    'fail',
+    'skip',
+    'xfail',
+    'importorskip',
+    'exit',
+    'mark',
+    'param',
+    'approx',
+    '_fillfuncargs',
+
+    'Item',
+    'File',
+    'Collector',
+    'Session',
+    'Module',
+    'Class',
+    'Instance',
+    'Function',
+    'Generator',
+    'raises',
+
+
 ]
 
-if __name__ == '__main__': # if run as a script or by 'python -m pytest'
+if __name__ == '__main__':
+    # if run as a script or by 'python -m pytest'
     # we trigger the below "else" condition by the following import
     import pytest
     raise SystemExit(pytest.main())
+else:
 
-# else we are imported
-
-from _pytest.config import (
-    main, UsageError, _preloadplugins, cmdline,
-    hookspec, hookimpl
-)
-from _pytest import __version__
-
-_preloadplugins() # to populate pytest.* namespace so help(pytest) works
-
+    from _pytest.compat import _setup_collect_fakemodule
+    _preloadplugins()  # to populate pytest.* namespace so help(pytest) works
+    _setup_collect_fakemodule()