Merge branch 'tests_coverage' into 'master'

instrument coverage on tests and require 100% coverage there

See merge request pycqa/flake8!414

.coveragerc

@@ -3,6 +3,7 @@ parallel = True
 branch = True
 source =
     flake8
+    tests
 omit =
     # Don't complain if non-runnable code isn't run
     */__main__.py

tests/integration/subdir/aplugin.py

@@ -9,8 +9,6 @@ class ExtensionTestPlugin2(object):
 
     def __init__(self, tree):
         """Construct an instance of test plugin."""
-        pass
 
     def run(self):
         """Do nothing."""
-        pass

tests/integration/test_plugins.py

@@ -14,11 +14,9 @@ class ExtensionTestPlugin(object):
 
     def __init__(self, tree):
         """Construct an instance of test plugin."""
-        pass
 
     def run(self):
         """Do nothing."""
-        pass
 
     @classmethod
     def add_options(cls, parser):
@@ -34,11 +32,9 @@ class ReportTestPlugin(object):
 
     def __init__(self, tree):
         """Construct an instance of test plugin."""
-        pass
 
     def run(self):
         """Do nothing."""
-        pass
 
 
 def test_enable_local_plugin_from_config():

tests/unit/test_checker_manager.py

@@ -73,5 +73,7 @@ def test_make_checkers():
             with mock.patch('flake8.processor.FileProcessor'):
                 manager.make_checkers()
 
-    for file_checker in manager.checkers:
+    assert manager._all_checkers
+    for file_checker in manager._all_checkers:
         assert file_checker.filename in files
+    assert not manager.checkers  # the files don't exist

tests/unit/test_file_processor.py

@@ -13,8 +13,7 @@ def test_read_lines_splits_lines(default_options):
     file_processor = processor.FileProcessor(__file__, default_options)
     lines = file_processor.lines
     assert len(lines) > 5
-    assert any('"""Tests for the FileProcessor class."""' in line.rstrip()
-               for line in lines)
+    assert lines[0].strip() == '"""Tests for the FileProcessor class."""'
 
 
 def _lines_from_file(tmpdir, contents, options):

tests/unit/test_legacy_api.py

@@ -126,7 +126,7 @@ def test_styleguide_init_report():
 
     class FakeFormatter(formatter.BaseFormatter):
         def format(self, *args):
-            pass
+            raise NotImplementedError
 
     style_guide.init_report(FakeFormatter)
     app.make_formatter.assert_called_once_with(FakeFormatter)

tests/unit/test_style_guide.py

@@ -78,10 +78,12 @@ def test_style_guide_manager_pre_file_ignores_parsing():
     options = create_options(per_file_ignores=PER_FILE_IGNORES_UNPARSED)
     guide = style_guide.StyleGuideManager(options, formatter=formatter)
     assert len(guide.style_guides) == 5
-    assert list(map(utils.normalize_path,
-                    ["first_file.py", "second_file.py", "third_file.py",
-                        "sub_dir/*"])
-                ) == [g.filename for g in guide.style_guides[1:]]
+    expected = [
+        utils.normalize_path(p) for p in [
+            "first_file.py", "second_file.py", "third_file.py", "sub_dir/*",
+        ]
+    ]
+    assert expected == [g.filename for g in guide.style_guides[1:]]
 
 
 @pytest.mark.parametrize('ignores,violation,filename,handle_error_return', [

tests/unit/test_utils.py

@@ -241,7 +241,7 @@ def test_parameters_for_class_plugin():
     """Verify that we can retrieve the parameters for a class plugin."""
     class FakeCheck(object):
         def __init__(self, tree):
-            pass
+            raise NotImplementedError
 
     plugin = plugin_manager.Plugin('plugin-name', object())
     plugin._plugin = FakeCheck
@@ -251,7 +251,7 @@ def test_parameters_for_class_plugin():
 def test_parameters_for_function_plugin():
     """Verify that we retrieve the parameters for a function plugin."""
     def fake_plugin(physical_line, self, tree, optional=None):
-        pass
+        raise NotImplementedError
 
     plugin = plugin_manager.Plugin('plugin-name', object())
     plugin._plugin = fake_plugin

tox.ini

@@ -11,6 +11,8 @@ commands =
     coverage run -m pytest {posargs}
     coverage combine
     coverage report
+    # ensure 100% coverage of tests
+    coverage report --fail-under 100 --include tests/*
 
 [testenv:venv]
 deps =