Merge branch 'example-project' into 'master'

Add an example plugin project to source tree

Necessary to start investigating issue #239

See merge request !128

example-plugin/setup.py

@@ -0,0 +1,32 @@
+# -*- coding: utf-8 -*-
+import setuptools
+
+setuptools.setup(
+    name='flake8-example-plugin',
+    license='MIT',
+    version='1.0.0',
+    description='Example plugin to Flake8',
+    author='Ian Cordasco',
+    author_email='graffatcolmingov@gmail.com',
+    url='https://gitlab.com/pycqa/flake8',
+    package_dir={'': 'src/'},
+    packages=['flake8_example_plugin'],
+    entry_points={
+        'flake8.extension': [
+            'X1 = flake8_example_plugin:ExampleOne',
+            'X2 = flake8_example_plugin:ExampleTwo',
+        ],
+    },
+    classifiers=[
+        'Framework :: Flake8',
+        'License :: OSI Approved :: MIT License',
+        'Programming Language :: Python',
+        'Programming Language :: Python :: 2',
+        'Programming Language :: Python :: 2.7',
+        'Programming Language :: Python :: 3',
+        'Programming Language :: Python :: 3.4',
+        'Programming Language :: Python :: 3.5',
+        'Topic :: Software Development :: Libraries :: Python Modules',
+        'Topic :: Software Development :: Quality Assurance',
+    ],
+)

example-plugin/src/flake8_example_plugin/__init__.py

@@ -0,0 +1,9 @@
+"""Module for an example Flake8 plugin."""
+
+from .on_by_default import ExampleOne
+from .off_by_default import ExampleTwo
+
+__all__ = (
+    'ExampleOne',
+    'ExampleTwo',
+)

example-plugin/src/flake8_example_plugin/off_by_default.py

@@ -0,0 +1,17 @@
+"""Our first example plugin."""
+
+
+class ExampleTwo(object):
+    """Second Example Plugin."""
+    name = 'off-by-default-example-plugin'
+    version = '1.0.0'
+
+    off_by_default = True
+
+    def __init__(self, tree):
+        self.tree = tree
+
+    def run(self):
+        """Do nothing."""
+        yield (1, 0, 'X200 The off-by-default plugin was enabled',
+               'OffByDefaultPlugin')

example-plugin/src/flake8_example_plugin/on_by_default.py

@@ -0,0 +1,15 @@
+"""Our first example plugin."""
+
+
+class ExampleOne(object):
+    """First Example Plugin."""
+    name = 'on-by-default-example-plugin'
+    version = '1.0.0'
+
+    def __init__(self, tree):
+        self.tree = tree
+
+    def run(self):
+        """Do nothing."""
+        for message in []:
+            yield message

src/flake8/style_guide.py

@@ -65,6 +65,7 @@ class StyleGuide(object):
         self._selected = tuple(options.select)
         self._extended_selected = tuple(options.extended_default_select)
         self._ignored = tuple(options.ignore)
+        self._enabled_extensions = tuple(options.enable_extensions)
         self._decision_cache = {}
         self._parsed_diff = {}
 
@@ -81,10 +82,10 @@ class StyleGuide(object):
             Ignored.Implicitly if the selected list is not empty but no match
             was found.
         """
-        if not self._selected:
+        if not (self._selected or self._enabled_extensions):
             return Selected.Implicitly
 
-        if code.startswith(self._selected):
+        if code.startswith(self._selected + self._enabled_extensions):
             return Selected.Explicitly
 
         # If it was not explicitly selected, it may have been implicitly

tests/unit/test_style_guide.py

@@ -15,6 +15,7 @@ def create_options(**kwargs):
     kwargs.setdefault('extended_default_select', [])
     kwargs.setdefault('ignore', [])
     kwargs.setdefault('disable_noqa', False)
+    kwargs.setdefault('enable_extensions', [])
     return optparse.Values(kwargs)
 
 
@@ -50,18 +51,24 @@ def test_is_user_ignored_implicitly_selects_errors(ignore_list, error_code):
     assert guide.is_user_ignored(error_code) is style_guide.Selected.Implicitly
 
 
-@pytest.mark.parametrize('select_list,error_code', [
+@pytest.mark.parametrize('select_list,enable_extensions,error_code', [
-    (['E111', 'E121'], 'E111'),
+    (['E111', 'E121'], [], 'E111'),
-    (['E111', 'E121'], 'E121'),
+    (['E111', 'E121'], [], 'E121'),
-    (['E11', 'E12'], 'E121'),
+    (['E11', 'E12'], [], 'E121'),
-    (['E2', 'E12'], 'E121'),
+    (['E2', 'E12'], [], 'E121'),
-    (['E2', 'E12'], 'E211'),
+    (['E2', 'E12'], [], 'E211'),
+    (['E1'], ['E2'], 'E211'),
+    ([], ['E2'], 'E211'),
 ])
-def test_is_user_selected_selects_errors(select_list, error_code):
+def test_is_user_selected_selects_errors(select_list, enable_extensions,
+                                         error_code):
     """Verify we detect users explicitly selecting an error."""
-    guide = style_guide.StyleGuide(create_options(select=select_list),
+    guide = style_guide.StyleGuide(
-                                   listener_trie=None,
+        options=create_options(select=select_list,
-                                   formatter=None)
+                               enable_extensions=enable_extensions),
+        listener_trie=None,
+        formatter=None,
+    )
 
     assert (guide.is_user_selected(error_code) is
             style_guide.Selected.Explicitly)