Merge pull request #1044 from adamjstewart/features/sncosmo

Add py-sncosmo package

9 files changed, 432 insertions, 101 deletions

diff --git a/var/spack/repos/builtin/packages/py-astropy/package.py b/var/spack/repos/builtin/packages/py-astropy/package.py
index 86875bbcae..a9962777dc 100644
--- a/var/spack/repos/builtin/packages/py-astropy/package.py
+++ b/var/spack/repos/builtin/packages/py-astropy/package.py
@@ -24,29 +24,38 @@
 ##############################################################################
 from spack import *
 
+
 class PyAstropy(Package):
-    """
-    The Astropy Project is a community effort to develop a single core
+    """The Astropy Project is a community effort to develop a single core
     package for Astronomy in Python and foster interoperability between
-    Python astronomy packages.
-    """
+    Python astronomy packages."""
+
     homepage = 'http://www.astropy.org/'
+    url = 'https://pypi.python.org/packages/source/a/astropy/astropy-1.1.2.tar.gz'
 
+    version('1.1.2',     'cbe32023b5b1177d1e2498a0d00cda51')
     version('1.1.post1', 'b52919f657a37d45cc45f5cb0f58c44d')
 
-    def url_for_version(self, version):
-        return 'https://pypi.python.org/packages/source/a/astropy/astropy-{0}.tar.gz'.format(version)
-
+    # Required dependencies
     extends('python')
+    depends_on('py-numpy')
 
-    depends_on('cfitsio')
-    depends_on('expat')
+    # Optional dependencies
     depends_on('py-h5py')
-    depends_on('py-numpy')
+    depends_on('py-beautifulsoup4')
+    depends_on('py-pyyaml')
     depends_on('py-scipy')
+    depends_on('libxml2')
+    depends_on('py-matplotlib')
+    depends_on('py-pytz')
+    depends_on('py-scikit-image')
+    depends_on('py-pandas')
+
+    # System dependencies
+    depends_on('cfitsio')
+    depends_on('expat')
 
     def install(self, spec, prefix):
         python('setup.py', 'build', '--use-system-cfitsio',
-                                    '--use-system-expat')
-        python('setup.py', 'install', '--prefix=' + prefix)
-
+               '--use-system-expat')
+        python('setup.py', 'install', '--prefix={0}'.format(prefix))
diff --git a/var/spack/repos/builtin/packages/py-beautifulsoup4/package.py b/var/spack/repos/builtin/packages/py-beautifulsoup4/package.py
new file mode 100644
index 0000000000..64368fe70d
--- /dev/null
+++ b/var/spack/repos/builtin/packages/py-beautifulsoup4/package.py
@@ -0,0 +1,41 @@
+##############################################################################
+# Copyright (c) 2013-2016, Lawrence Livermore National Security, LLC.
+# Produced at the Lawrence Livermore National Laboratory.
+#
+# This file is part of Spack.
+# Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
+# LLNL-CODE-647188
+#
+# For details, see https://github.com/llnl/spack
+# Please also see the LICENSE file for our notice and the LGPL.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License (as
+# published by the Free Software Foundation) version 2.1, February 1999.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
+# conditions of the GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+##############################################################################
+from spack import *
+
+
+class PyBeautifulsoup4(Package):
+    """Beautiful Soup is a Python library for pulling data out of HTML and
+    XML files. It works with your favorite parser to provide idiomatic ways
+    of navigating, searching, and modifying the parse tree."""
+
+    homepage = "https://www.crummy.com/software/BeautifulSoup"
+    url = "https://pypi.python.org/packages/source/b/beautifulsoup4/beautifulsoup4-4.4.1.tar.gz"
+
+    version('4.4.1', '8fbd9a7cac0704645fa20d1419036815')
+
+    extends('python')
+
+    def install(self, spec, prefix):
+        python('setup.py', 'install', '--prefix={0}'.format(prefix))
diff --git a/var/spack/repos/builtin/packages/py-emcee/package.py b/var/spack/repos/builtin/packages/py-emcee/package.py
new file mode 100644
index 0000000000..d57ef4bd76
--- /dev/null
+++ b/var/spack/repos/builtin/packages/py-emcee/package.py
@@ -0,0 +1,41 @@
+##############################################################################
+# Copyright (c) 2013-2016, Lawrence Livermore National Security, LLC.
+# Produced at the Lawrence Livermore National Laboratory.
+#
+# This file is part of Spack.
+# Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
+# LLNL-CODE-647188
+#
+# For details, see https://github.com/llnl/spack
+# Please also see the LICENSE file for our notice and the LGPL.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License (as
+# published by the Free Software Foundation) version 2.1, February 1999.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
+# conditions of the GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+##############################################################################
+from spack import *
+
+
+class PyEmcee(Package):
+    """emcee is an MIT licensed pure-Python implementation of Goodman & Weare's
+    Affine Invariant Markov chain Monte Carlo (MCMC) Ensemble sampler."""
+
+    homepage = "http://dan.iel.fm/emcee/current/"
+    url = "https://pypi.python.org/packages/source/e/emcee/emcee-2.1.0.tar.gz"
+
+    version('2.1.0', 'c6b6fad05c824d40671d4a4fc58dfff7')
+
+    extends('python')
+    depends_on('py-numpy')
+
+    def install(self, spec, prefix):
+        python('setup.py', 'install', '--prefix={0}'.format(prefix))
diff --git a/var/spack/repos/builtin/packages/py-h5py/package.py b/var/spack/repos/builtin/packages/py-h5py/package.py
index a8eb027ba5..0180b658f5 100644
--- a/var/spack/repos/builtin/packages/py-h5py/package.py
+++ b/var/spack/repos/builtin/packages/py-h5py/package.py
@@ -23,23 +23,42 @@
 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 ##############################################################################
 from spack import *
-import re
+
 
 class PyH5py(Package):
-    """The h5py package provides both a high- and low-level interface to the HDF5 library from Python."""
+    """The h5py package provides both a high- and low-level interface to the
+    HDF5 library from Python."""
+
     homepage = "https://pypi.python.org/pypi/h5py"
     url      = "https://pypi.python.org/packages/source/h/h5py/h5py-2.4.0.tar.gz"
 
-    version('2.4.0', '80c9a94ae31f84885cc2ebe1323d6758')
+    version('2.6.0', 'ec476211bd1de3f5ac150544189b0bf4')
     version('2.5.0', '6e4301b5ad5da0d51b0a1e5ac19e3b74')
+    version('2.4.0', '80c9a94ae31f84885cc2ebe1323d6758')
+
+    variant('mpi', default=False, description='Build with MPI support')
 
-    extends('python', ignore=lambda f: re.match(r'bin/cy*', f))
-    depends_on('hdf5')
-    depends_on('py-numpy')
-    depends_on('py-cython')
+    extends('python')
+
+    # Build dependencies
+    depends_on('py-cython@0.19:')
+    depends_on('pkg-config')
+    depends_on('hdf5@1.8.4:+mpi', when='+mpi')
+    depends_on('hdf5@1.8.4:~mpi', when='~mpi')
+    depends_on('mpi', when='+mpi')
+
+    # Build and runtime dependencies
+    depends_on('py-numpy@1.6.1:')
+
+    # Runtime dependencies
     depends_on('py-six')
-    depends_on('py-pkgconfig')
 
     def install(self, spec, prefix):
-        python('setup.py', 'configure', '--hdf5=%s' % spec['hdf5'].prefix)
-        python('setup.py', 'install', '--prefix=%s' % prefix)
+        python('setup.py', 'configure',
+               '--hdf5={0}'.format(spec['hdf5'].prefix))
+
+        if '+mpi' in spec:
+            env['CC'] = spec['mpi'].mpicc
+            python('setup.py', 'configure', '--mpi')
+
+        python('setup.py', 'install', '--prefix={0}'.format(prefix))
diff --git a/var/spack/repos/builtin/packages/py-iminuit/package.py b/var/spack/repos/builtin/packages/py-iminuit/package.py
new file mode 100644
index 0000000000..47751a702d
--- /dev/null
+++ b/var/spack/repos/builtin/packages/py-iminuit/package.py
@@ -0,0 +1,46 @@
+##############################################################################
+# Copyright (c) 2013-2016, Lawrence Livermore National Security, LLC.
+# Produced at the Lawrence Livermore National Laboratory.
+#
+# This file is part of Spack.
+# Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
+# LLNL-CODE-647188
+#
+# For details, see https://github.com/llnl/spack
+# Please also see the LICENSE file for our notice and the LGPL.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License (as
+# published by the Free Software Foundation) version 2.1, February 1999.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
+# conditions of the GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+##############################################################################
+from spack import *
+
+
+class PyIminuit(Package):
+    """Interactive IPython-Friendly Minimizer based on SEAL Minuit2."""
+
+    homepage = "https://pypi.python.org/pypi/iminuit"
+    url      = "https://pypi.python.org/packages/source/i/iminuit/iminuit-1.2.tar.gz"
+
+    version('1.2', '4701ec472cae42015e26251703e6e984')
+
+    # Required dependencies
+    extends('python')
+    depends_on('py-setuptools')
+
+    # Optional dependencies
+    depends_on('py-numpy')
+    depends_on('py-matplotlib')
+    depends_on('py-cython')
+
+    def install(self, spec, prefix):
+        python('setup.py', 'install', '--prefix={0}'.format(prefix))
diff --git a/var/spack/repos/builtin/packages/py-nestle/package.py b/var/spack/repos/builtin/packages/py-nestle/package.py
new file mode 100644
index 0000000000..16506e3eca
--- /dev/null
+++ b/var/spack/repos/builtin/packages/py-nestle/package.py
@@ -0,0 +1,44 @@
+##############################################################################
+# Copyright (c) 2013-2016, Lawrence Livermore National Security, LLC.
+# Produced at the Lawrence Livermore National Laboratory.
+#
+# This file is part of Spack.
+# Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
+# LLNL-CODE-647188
+#
+# For details, see https://github.com/llnl/spack
+# Please also see the LICENSE file for our notice and the LGPL.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License (as
+# published by the Free Software Foundation) version 2.1, February 1999.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
+# conditions of the GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+##############################################################################
+from spack import *
+
+
+class PyNestle(Package):
+    """Nested sampling algorithms for evaluating Bayesian evidence."""
+
+    homepage = "http://kbarbary.github.io/nestle/"
+    url = "https://pypi.python.org/packages/source/n/nestle/nestle-0.1.1.tar.gz"
+
+    version('0.1.1', '4875c0f9a0a8e263c1d7f5fa6ce604c5')
+
+    # Required dependencies
+    extends('python')
+    depends_on('py-numpy')
+
+    # Optional dependencies
+    depends_on('py-scipy')
+
+    def install(self, spec, prefix):
+        python('setup.py', 'install', '--prefix={0}'.format(prefix))
diff --git a/var/spack/repos/builtin/packages/py-sncosmo/package.py b/var/spack/repos/builtin/packages/py-sncosmo/package.py
new file mode 100644
index 0000000000..82ae2a2e69
--- /dev/null
+++ b/var/spack/repos/builtin/packages/py-sncosmo/package.py
@@ -0,0 +1,51 @@
+##############################################################################
+# Copyright (c) 2013-2016, Lawrence Livermore National Security, LLC.
+# Produced at the Lawrence Livermore National Laboratory.
+#
+# This file is part of Spack.
+# Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
+# LLNL-CODE-647188
+#
+# For details, see https://github.com/llnl/spack
+# Please also see the LICENSE file for our notice and the LGPL.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License (as
+# published by the Free Software Foundation) version 2.1, February 1999.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
+# conditions of the GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+##############################################################################
+from spack import *
+
+
+class PySncosmo(Package):
+    """SNCosmo is a Python library for high-level supernova cosmology
+    analysis."""
+
+    homepage = "http://sncosmo.readthedocs.io/"
+    url = "https://pypi.python.org/packages/source/s/sncosmo/sncosmo-1.2.0.tar.gz"
+
+    version('1.2.0', '028e6d1dc84ab1c17d2f3b6378b2cb1e')
+
+    # Required dependencies
+    # py-sncosmo binaries are duplicates of those from py-astropy
+    extends('python', ignore=r'bin/.*')
+    depends_on('py-numpy')
+    depends_on('py-scipy')
+    depends_on('py-astropy')
+
+    # Recommended dependencies
+    depends_on('py-matplotlib')
+    depends_on('py-iminuit')
+    depends_on('py-emcee')
+    depends_on('py-nestle')
+
+    def install(self, spec, prefix):
+        python('setup.py', 'install', '--prefix={0}'.format(prefix))
diff --git a/var/spack/repos/builtin/packages/py-wcsaxes/package.py b/var/spack/repos/builtin/packages/py-wcsaxes/package.py
new file mode 100644
index 0000000000..b0adbe3658
--- /dev/null
+++ b/var/spack/repos/builtin/packages/py-wcsaxes/package.py
@@ -0,0 +1,43 @@
+##############################################################################
+# Copyright (c) 2013-2016, Lawrence Livermore National Security, LLC.
+# Produced at the Lawrence Livermore National Laboratory.
+#
+# This file is part of Spack.
+# Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
+# LLNL-CODE-647188
+#
+# For details, see https://github.com/llnl/spack
+# Please also see the LICENSE file for our notice and the LGPL.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License (as
+# published by the Free Software Foundation) version 2.1, February 1999.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
+# conditions of the GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+##############################################################################
+from spack import *
+
+
+class PyWcsaxes(Package):
+    """WCSAxes is a framework for making plots of Astronomical data
+    in Matplotlib."""
+
+    homepage = "http://wcsaxes.readthedocs.io/en/latest/index.html"
+    url      = "https://github.com/astrofrog/wcsaxes/archive/v0.8.tar.gz"
+
+    version('0.8', 'de1c60fdae4c330bf5ddb9f1ab5ab920')
+
+    extends('python', ignore=r'bin/pbr')
+    depends_on('py-numpy')
+    depends_on('py-matplotlib')
+    depends_on('py-astropy')
+
+    def install(self, spec, prefix):
+        python('setup.py', 'install', '--prefix={0}'.format(prefix))
diff --git a/var/spack/repos/builtin/packages/python/package.py b/var/spack/repos/builtin/packages/python/package.py
index 86c12498e1..b6a62bf742 100644
--- a/var/spack/repos/builtin/packages/python/package.py
+++ b/var/spack/repos/builtin/packages/python/package.py
@@ -22,9 +22,6 @@
 # License along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 ##############################################################################
-import functools
-import glob
-import inspect
 import os
 import re
 from contextlib import closing
@@ -37,11 +34,10 @@ from spack.util.environment import *
 
 class Python(Package):
     """The Python programming language."""
+
     homepage = "http://www.python.org"
     url      = "http://www.python.org/ftp/python/2.7.8/Python-2.7.8.tgz"
 
-    extendable = True
-
     version('3.5.1', 'be78e48cdfc1a7ad90efff146dce6cfe')
     version('3.5.0', 'a56c0c0b45d75a0ec9c6dee933c41c36')
     version('2.7.11', '6b6076ec9e93f05dd63e47eb9c15728b', preferred=True)
@@ -49,6 +45,8 @@ class Python(Package):
     version('2.7.9', '5eebcaa0030dc4061156d3429657fb83')
     version('2.7.8', 'd4bca0159acb0b44a781292b5231936f')
 
+    extendable = True
+
     depends_on("openssl")
     depends_on("bzip2")
     depends_on("readline")
@@ -64,39 +62,63 @@ class Python(Package):
         # Rest of install is pretty standard except setup.py needs to
         # be able to read the CPPFLAGS and LDFLAGS as it scans for the
         # library and headers to build
-        configure_args= [
-                  "--prefix=%s" % prefix,
-                  "--with-threads",
-                  "--enable-shared",
-                  "CPPFLAGS=-I%s/include -I%s/include -I%s/include -I%s/include -I%s/include -I%s/include" % (
-                       spec['openssl'].prefix, spec['bzip2'].prefix,
-                       spec['readline'].prefix, spec['ncurses'].prefix,
-                       spec['sqlite'].prefix, spec['zlib'].prefix),
-                  "LDFLAGS=-L%s/lib -L%s/lib -L%s/lib -L%s/lib -L%s/lib -L%s/lib" % (
-                       spec['openssl'].prefix, spec['bzip2'].prefix,
-                       spec['readline'].prefix, spec['ncurses'].prefix,
-                       spec['sqlite'].prefix, spec['zlib'].prefix)
-                  ]
+        cppflags = ' -I'.join([
+            spec['openssl'].prefix.include,  spec['bzip2'].prefix.include,
+            spec['readline'].prefix.include, spec['ncurses'].prefix.include,
+            spec['sqlite'].prefix.include,   spec['zlib'].prefix.include
+        ])
+
+        ldflags = ' -L'.join([
+            spec['openssl'].prefix.lib,  spec['bzip2'].prefix.lib,
+            spec['readline'].prefix.lib, spec['ncurses'].prefix.lib,
+            spec['sqlite'].prefix.lib,   spec['zlib'].prefix.lib
+        ])
+
+        config_args = [
+            "--prefix={0}".format(prefix),
+            "--with-threads",
+            "--enable-shared",
+            "CPPFLAGS=-I{0}".format(cppflags),
+            "LDFLAGS=-L{0}".format(ldflags)
+        ]
+
         if spec.satisfies('@3:'):
-            configure_args.append('--without-ensurepip')
-        configure(*configure_args)
+            config_args.append('--without-ensurepip')
+
+        configure(*config_args)
+
         make()
         make("install")
 
-        # Modify compiler paths in configuration files. This is necessary for
-        # building site packages outside of spack
-        filter_file(r'([/s]=?)([\S=]*)/lib/spack/env(/[^\s/]*)?/(\S*)(\s)',
-                    (r'\4\5'),
-                    join_path(prefix.lib, 'python%d.%d' % self.version[:2], '_sysconfigdata.py'))
+        self.filter_compilers(spec, prefix)
+
+    def filter_compilers(self, spec, prefix):
+        """Run after install to tell the configuration files and Makefiles
+        to use the compilers that Spack built the package with.
+
+        If this isn't done, they'll have CC and CXX set to Spack's generic
+        cc and c++. We want them to be bound to whatever compiler
+        they were built with."""
+
+        kwargs = {'ignore_absent': True, 'backup': False, 'string': True}
 
-        python3_version = ''
+        dirname = join_path(prefix.lib,
+                            'python{0}'.format(self.version.up_to(2)))
+
+        config = 'config'
         if spec.satisfies('@3:'):
-            python3_version = '-%d.%dm' % self.version[:2]
-        makefile_filepath = join_path(prefix.lib, 'python%d.%d' % self.version[:2], 'config%s' % python3_version, 'Makefile')
-        filter_file(r'([/s]=?)([\S=]*)/lib/spack/env(/[^\s/]*)?/(\S*)(\s)',
-                    (r'\4\5'),
-                    makefile_filepath)
+            config = 'config-{0}m'.format(self.version.up_to(2))
+
+        files = [
+            '_sysconfigdata.py',
+            join_path(config, 'Makefile')
+        ]
 
+        for filename in files:
+            filter_file(env['CC'],  self.compiler.cc,
+                        join_path(dirname, filename), **kwargs)
+            filter_file(env['CXX'], self.compiler.cxx,
+                        join_path(dirname, filename), **kwargs)
 
     # ========================================================================
     # Set up environment to make install easy for python extensions.
@@ -104,57 +126,59 @@ class Python(Package):
 
     @property
     def python_lib_dir(self):
-        return os.path.join('lib', 'python%d.%d' % self.version[:2])
-
+        return join_path('lib', 'python{0}'.format(self.version.up_to(2)))
 
     @property
     def python_include_dir(self):
-        return os.path.join('include', 'python%d.%d' % self.version[:2])
-
+        return join_path('include', 'python{0}'.format(self.version.up_to(2)))
 
     @property
     def site_packages_dir(self):
-        return os.path.join(self.python_lib_dir, 'site-packages')
-
+        return join_path(self.python_lib_dir, 'site-packages')
 
     def setup_dependent_environment(self, spack_env, run_env, extension_spec):
-        # TODO: do this only for actual extensions.
+        """Set PYTHONPATH to include site-packages dir for the
+        extension and any other python extensions it depends on."""
 
-        # Set PYTHONPATH to include site-packages dir for the
-        # extension and any other python extensions it depends on.
         python_paths = []
         for d in extension_spec.traverse():
             if d.package.extends(self.spec):
-                python_paths.append(os.path.join(d.prefix, self.site_packages_dir))
+                python_paths.append(join_path(d.prefix,
+                                              self.site_packages_dir))
 
         pythonpath = ':'.join(python_paths)
         spack_env.set('PYTHONPATH', pythonpath)
 
-        # For run time environment set only the path for extension_spec and prepend it to PYTHONPATH
+        # For run time environment set only the path for
+        # extension_spec and prepend it to PYTHONPATH
         if extension_spec.package.extends(self.spec):
-            run_env.prepend_path('PYTHONPATH', os.path.join(extension_spec.prefix, self.site_packages_dir))
-
+            run_env.prepend_path('PYTHONPATH', join_path(
+                extension_spec.prefix, self.site_packages_dir))
 
     def setup_dependent_package(self, module, ext_spec):
-        """
-        Called before python modules' install() methods.
+        """Called before python modules' install() methods.
 
         In most cases, extensions will only need to have one line::
 
-        python('setup.py', 'install', '--prefix=%s' % prefix)
-        """
+        python('setup.py', 'install', '--prefix={0}'.format(prefix))"""
+
         # Python extension builds can have a global python executable function
-        if self.version >= Version("3.0.0") and self.version < Version("4.0.0"):
-            module.python = Executable(join_path(self.spec.prefix.bin, 'python3'))
+        if Version("3.0.0") <= self.version < Version("4.0.0"):
+            module.python = Executable(join_path(self.spec.prefix.bin,
+                                                 'python3'))
         else:
-            module.python = Executable(join_path(self.spec.prefix.bin, 'python'))
+            module.python = Executable(join_path(self.spec.prefix.bin,
+                                                 'python'))
 
         # Add variables for lib/pythonX.Y and lib/pythonX.Y/site-packages dirs.
-        module.python_lib_dir     = os.path.join(ext_spec.prefix, self.python_lib_dir)
-        module.python_include_dir = os.path.join(ext_spec.prefix, self.python_include_dir)
-        module.site_packages_dir  = os.path.join(ext_spec.prefix, self.site_packages_dir)
-
-        # Make the site packages directory for extensions, if it does not exist already.
+        module.python_lib_dir     = join_path(ext_spec.prefix,
+                                              self.python_lib_dir)
+        module.python_include_dir = join_path(ext_spec.prefix,
+                                              self.python_include_dir)
+        module.site_packages_dir  = join_path(ext_spec.prefix,
+                                              self.site_packages_dir)
+
+        # Make the site packages directory for extensions
         if ext_spec.package.is_extension:
             mkdirp(module.site_packages_dir)
 
@@ -167,25 +191,28 @@ class Python(Package):
         ignore_arg = args.get('ignore', lambda f: False)
 
         # Always ignore easy-install.pth, as it needs to be merged.
-        patterns = [r'easy-install\.pth$']
+        patterns = [r'site-packages/easy-install\.pth$']
 
         # Ignore pieces of setuptools installed by other packages.
+        # Must include directory name or it will remove all site*.py files.
         if ext_pkg.name != 'py-setuptools':
-            patterns.append(r'/site[^/]*\.pyc?$')
-            patterns.append(r'setuptools\.pth')
-            patterns.append(r'bin/easy_install[^/]*$')
-            patterns.append(r'setuptools.*egg$')
+            patterns.extend([
+                r'bin/easy_install[^/]*$',
+                r'site-packages/setuptools[^/]*\.egg$',
+                r'site-packages/setuptools\.pth$',
+                r'site-packages/site[^/]*\.pyc?$',
+                r'site-packages/__pycache__/site[^/]*\.pyc?$'
+            ])
         if ext_pkg.name != 'py-numpy':
             patterns.append(r'bin/f2py$')
 
         return match_predicate(ignore_arg, patterns)
 
-
     def write_easy_install_pth(self, exts):
         paths = []
         for ext in sorted(exts.values()):
-            ext_site_packages = os.path.join(ext.prefix, self.site_packages_dir)
-            easy_pth = "%s/easy-install.pth" % ext_site_packages
+            ext_site_packages = join_path(ext.prefix, self.site_packages_dir)
+            easy_pth = join_path(ext_site_packages, "easy-install.pth")
 
             if not os.path.isfile(easy_pth):
                 continue
@@ -195,15 +222,18 @@ class Python(Package):
                     line = line.rstrip()
 
                     # Skip lines matching these criteria
-                    if not line: continue
-                    if re.search(r'^(import|#)', line): continue
-                    if (ext.name != 'py-setuptools' and
-                        re.search(r'setuptools.*egg$', line)): continue
+                    if not line:
+                        continue
+                    if re.search(r'^(import|#)', line):
+                        continue
+                    if ((ext.name != 'py-setuptools' and
+                         re.search(r'setuptools.*egg$', line))):
+                        continue
 
                     paths.append(line)
 
-        site_packages = os.path.join(self.prefix, self.site_packages_dir)
-        main_pth = "%s/easy-install.pth" % site_packages
+        site_packages = join_path(self.prefix, self.site_packages_dir)
+        main_pth = join_path(site_packages, "easy-install.pth")
 
         if not paths:
             if os.path.isfile(main_pth):
@@ -211,15 +241,22 @@ class Python(Package):
 
         else:
             with closing(open(main_pth, 'w')) as f:
-                f.write("import sys; sys.__plen = len(sys.path)\n")
+                f.write("""
+import sys
+sys.__plen = len(sys.path)
+""")
                 for path in paths:
-                    f.write("%s\n" % path)
-                f.write("import sys; new=sys.path[sys.__plen:]; del sys.path[sys.__plen:]; "
-                        "p=getattr(sys,'__egginsert',0); sys.path[p:p]=new; sys.__egginsert = p+len(new)\n")
-
+                    f.write("{0}\n".format(path))
+                f.write("""
+new = sys.path[sys.__plen:]
+del sys.path[sys.__plen:]
+p = getattr(sys, '__egginsert', 0)
+sys.path[p:p] = new
+sys.__egginsert = p + len(new)
+""")
 
     def activate(self, ext_pkg, **args):
-        ignore=self.python_ignore(ext_pkg, args)
+        ignore = self.python_ignore(ext_pkg, args)
         args.update(ignore=ignore)
 
         super(Python, self).activate(ext_pkg, **args)
@@ -228,12 +265,12 @@ class Python(Package):
         exts[ext_pkg.name] = ext_pkg.spec
         self.write_easy_install_pth(exts)
 
-
     def deactivate(self, ext_pkg, **args):
         args.update(ignore=self.python_ignore(ext_pkg, args))
         super(Python, self).deactivate(ext_pkg, **args)
 
         exts = spack.install_layout.extension_map(self.spec)
-        if ext_pkg.name in exts:        # Make deactivate idempotent.
+        # Make deactivate idempotent
+        if ext_pkg.name in exts:
             del exts[ext_pkg.name]
             self.write_easy_install_pth(exts)