Add support for Pip's extra dependencies in YAML config.

readthedocs_build/config/config.py

@@ -9,6 +9,7 @@
 from .validation import validate_choice
 from .validation import validate_directory
 from .validation import validate_file
+from .validation import validate_string
 from .validation import ValidationError
 
 
@@ -74,6 +75,8 @@ class BuildConfig(dict):
     TYPE_REQUIRED_MESSAGE = 'Missing key "type"'
     CONF_FILE_REQUIRED_MESSAGE = 'Missing key "conf_file"'
     PYTHON_INVALID_MESSAGE = '"python" section must be a mapping.'
+    PYTHON_EXTRA_REQUIREMENTS_INVALID_MESSAGE = (
+        '"python.extra_requirements" section must be a list.')
 
     def __init__(self, env_config, raw_config, source_file, source_position):
         self.env_config = env_config
@@ -205,6 +208,7 @@ def validate_python(self):
         python = {
             'use_system_site_packages': False,
             'pip_install': False,
+            'extra_requirements': [],
             'setup_py_install': False,
             'setup_py_path': os.path.join(
                 os.path.dirname(self.source_file),
@@ -233,6 +237,20 @@ def validate_python(self):
                     python['pip_install'] = validate_bool(
                         raw_python['pip_install'])
 
+            # Validate extra_requirements.
+            if 'extra_requirements' in raw_python:
+                raw_extra_requirements = raw_python['extra_requirements']
+                if not isinstance(raw_extra_requirements, list):
+                    self.error(
+                        'python.extra_requirements',
+                        self.PYTHON_EXTRA_REQUIREMENTS_INVALID_MESSAGE,
+                        code=PYTHON_INVALID)
+                for extra_name in raw_extra_requirements:
+                    with self.catch_validation_error(
+                            'python.extra_requirements'):
+                        python['extra_requirements'].append(
+                            validate_string(extra_name))
+
             # Validate setup_py_install.
             if 'setup_py_install' in raw_python:
                 with self.catch_validation_error('python.setup_py_install'):

readthedocs_build/config/test_config.py

@@ -179,6 +179,31 @@ def test_python_pip_install_default():
     assert build['python']['pip_install'] is False
 
 
+def describe_validate_python_extra_requirements():
+
+    def it_defaults_to_list():
+        build = get_build_config({'python': {}})
+        build.validate_python()
+        # Default is an empty list.
+        assert build['python']['extra_requirements'] == []
+
+    def it_validates_is_a_list():
+        build = get_build_config(
+            {'python': {'extra_requirements': 'invalid'}})
+        with raises(InvalidConfig) as excinfo:
+            build.validate_python()
+        assert excinfo.value.key == 'python.extra_requirements'
+        assert excinfo.value.code == PYTHON_INVALID
+
+    @patch('readthedocs_build.config.config.validate_string')
+    def it_uses_validate_string(validate_string):
+        validate_string.return_value = True
+        build = get_build_config(
+            {'python': {'extra_requirements': ['tests']}})
+        build.validate_python()
+        validate_string.assert_any_call('tests')
+
+
 def describe_validate_use_system_site_packages():
     def it_defaults_to_false():
         build = get_build_config({'python': {}})

spec.rst

@@ -136,6 +136,11 @@ Following mapping keys are supported (all but the marked once are optional):
         path/to/requirements.txt``. Accepts version modifiers like
         ``setuptools>=18.0``.
 
+    ``extra_requirements``
+        A list of `extra requirements`_ sections to install, additionnaly to
+        the `package default dependencies`_. Ignored if the ``setup_install``
+        option below is ``true``.
+
     ``setup_install``
         If ``true``, then ``python setup.py install`` will be executed before
         building the docs.
@@ -146,3 +151,7 @@ Following mapping keys are supported (all but the marked once are optional):
 
 ``language``
     The language the doc is written in. Defaults to empty string.
+
+
+.. _extra requirements: http://setuptools.readthedocs.io/en/latest/setuptools.html#declaring-extras-optional-features-with-their-own-dependencies
+.. _package default dependencies: http://setuptools.readthedocs.io/en/latest/setuptools.html#declaring-dependencies