Modulefiles generated with a template engine (#3183)

* Module files now are generated using a template engine refers #2902 #3173

jinja2 has been hooked into Spack.

The python module `modules.py` has been splitted into several modules
under the python package `spack/modules`. Unit tests stressing module
file generation have been refactored accordingly.

The module file generator for Lmod has been extended to multi-providers
and deeper hierarchies.

* Improved the support for templates in module files.

Added an entry in `config.yaml` (`template_dirs`) to list all the
directories where Spack could find templates for `jinja2`.

Module file generators have a simple override mechanism to override
template selection ('modules.yaml' beats 'package.py' beats 'default').

* Added jinja2 and MarkupSafe to vendored packages.

* Spec.concretize() sets mutual spec-package references

The correct place to set the mutual references between spec and package
objects at the end of concretization. After a call to concretize we
should now be ensured that spec is the same object as spec.package.spec.

Code in `build_environment.py` that was performing the same operation
has been turned into an assertion to be defensive on the new behavior.

* Improved code and data layout for modules and related tests.

Common fixtures related to module file generation have been extracted
in `conftest.py`. All the mock configurations for module files have been
extracted from python code and have been put into their own yaml file.

Added a `context_property` decorator for the template engine, to make
it easy to define dictionaries out of properties.

The default for `verbose` in `modules.yaml` is now False instead of True.

* Extendable module file contexts + short description from docstring

The contexts that are used in conjunction with `jinja2` templates to
generate module files can now be extended from package.py and
modules.yaml.

Module files generators now infer the short description from package.py
docstring (and as you may expect it's the first paragraph)

* 'module refresh' regenerates all modules by default

`module refresh` without `--module-type` specified tries to
regenerate all known module types. The same holds true for `module rm`

Configure options used at build time are extracted and written into the
module files where possible.

* Fixed python3 compatibility, tests for Lmod and Tcl.

Added test for exceptional paths of execution when generating Lmod
module files.

Fixed a few compatibility issues with python3.

Fixed a bug in Tcl with naming_scheme and autoload + unit tests

* Updated module file tutorial docs. Fixed a few typos in docstrings.

The reference section for module files has been reorganized. The idea is
to have only three topics at the highest level:

  - shell support + spack load/unload use/unuse
  - module file generation (a.k.a. APIs + modules.yaml)
  - module file maintenance (spack module refresh/rm)

Module file generation will cover the entries in modules.yaml

Also:

  - Licenses have been updated to include NOTICE and extended to 2017
  - docstrings have been reformatted according to Google style

* Removed redundant arguments to RPackage and WafPackage.

All the callbacks in `RPackage` and `WafPackage` that are not build
phases have been modified not to accept a `spec` and a `prefix`
argument. This permits to leverage the common `configure_args` signature
to insert by default the configuration arguments into the generated
module files. I think it's preferable to handling those packages
differently than `AutotoolsPackage`. Besides only one package seems
to override one of these methods.

* Fixed broken indentation + improved resiliency of refresh

Fixed broken indentation in `spack module refresh` (probably a rebase
gone silently wrong?). Filter the writers for blacklisted specs before
searching for name clashes. An error with a single writer will not
stop regeneration, but instead will print a warning and continue
the command.

1 files changed, 185 insertions, 0 deletions

diff --git a/lib/spack/external/jinja2/tests.py b/lib/spack/external/jinja2/tests.py
new file mode 100644
index 0000000000..bd843b77bc
--- /dev/null
+++ b/lib/spack/external/jinja2/tests.py
@@ -0,0 +1,185 @@
+# -*- coding: utf-8 -*-
+"""
+    jinja2.tests
+    ~~~~~~~~~~~~
+
+    Jinja test functions. Used with the "is" operator.
+
+    :copyright: (c) 2017 by the Jinja Team.
+    :license: BSD, see LICENSE for more details.
+"""
+import re
+from collections import Mapping
+from jinja2.runtime import Undefined
+from jinja2._compat import text_type, string_types, integer_types
+import decimal
+
+number_re = re.compile(r'^-?\d+(\.\d+)?$')
+regex_type = type(number_re)
+
+
+test_callable = callable
+
+
+def test_odd(value):
+    """Return true if the variable is odd."""
+    return value % 2 == 1
+
+
+def test_even(value):
+    """Return true if the variable is even."""
+    return value % 2 == 0
+
+
+def test_divisibleby(value, num):
+    """Check if a variable is divisible by a number."""
+    return value % num == 0
+
+
+def test_defined(value):
+    """Return true if the variable is defined:
+
+    .. sourcecode:: jinja
+
+        {% if variable is defined %}
+            value of variable: {{ variable }}
+        {% else %}
+            variable is not defined
+        {% endif %}
+
+    See the :func:`default` filter for a simple way to set undefined
+    variables.
+    """
+    return not isinstance(value, Undefined)
+
+
+def test_undefined(value):
+    """Like :func:`defined` but the other way round."""
+    return isinstance(value, Undefined)
+
+
+def test_none(value):
+    """Return true if the variable is none."""
+    return value is None
+
+
+def test_lower(value):
+    """Return true if the variable is lowercased."""
+    return text_type(value).islower()
+
+
+def test_upper(value):
+    """Return true if the variable is uppercased."""
+    return text_type(value).isupper()
+
+
+def test_string(value):
+    """Return true if the object is a string."""
+    return isinstance(value, string_types)
+
+
+def test_mapping(value):
+    """Return true if the object is a mapping (dict etc.).
+
+    .. versionadded:: 2.6
+    """
+    return isinstance(value, Mapping)
+
+
+def test_number(value):
+    """Return true if the variable is a number."""
+    return isinstance(value, integer_types + (float, complex, decimal.Decimal))
+
+
+def test_sequence(value):
+    """Return true if the variable is a sequence. Sequences are variables
+    that are iterable.
+    """
+    try:
+        len(value)
+        value.__getitem__
+    except:
+        return False
+    return True
+
+
+def test_equalto(value, other):
+    """Check if an object has the same value as another object:
+
+    .. sourcecode:: jinja
+
+        {% if foo.expression is equalto 42 %}
+            the foo attribute evaluates to the constant 42
+        {% endif %}
+
+    This appears to be a useless test as it does exactly the same as the
+    ``==`` operator, but it can be useful when used together with the
+    `selectattr` function:
+
+    .. sourcecode:: jinja
+
+        {{ users|selectattr("email", "equalto", "foo@bar.invalid") }}
+
+    .. versionadded:: 2.8
+    """
+    return value == other
+
+
+def test_sameas(value, other):
+    """Check if an object points to the same memory address than another
+    object:
+
+    .. sourcecode:: jinja
+
+        {% if foo.attribute is sameas false %}
+            the foo attribute really is the `False` singleton
+        {% endif %}
+    """
+    return value is other
+
+
+def test_iterable(value):
+    """Check if it's possible to iterate over an object."""
+    try:
+        iter(value)
+    except TypeError:
+        return False
+    return True
+
+
+def test_escaped(value):
+    """Check if the value is escaped."""
+    return hasattr(value, '__html__')
+
+
+def test_greaterthan(value, other):
+    """Check if value is greater than other."""
+    return value > other
+
+
+def test_lessthan(value, other):
+    """Check if value is less than other."""
+    return value < other
+
+
+TESTS = {
+    'odd':              test_odd,
+    'even':             test_even,
+    'divisibleby':      test_divisibleby,
+    'defined':          test_defined,
+    'undefined':        test_undefined,
+    'none':             test_none,
+    'lower':            test_lower,
+    'upper':            test_upper,
+    'string':           test_string,
+    'mapping':          test_mapping,
+    'number':           test_number,
+    'sequence':         test_sequence,
+    'iterable':         test_iterable,
+    'callable':         test_callable,
+    'sameas':           test_sameas,
+    'equalto':          test_equalto,
+    'escaped':          test_escaped,
+    'greaterthan':      test_greaterthan,
+    'lessthan':         test_lessthan
+}