Remove pytest collection filter.

It's really only needed to get the pep8 options.

Author: QuLogic

conftest.py

@@ -9,68 +9,11 @@
 import matplotlib
 matplotlib.use('agg')
 
-from matplotlib import default_test_modules
-
-
-IGNORED_TESTS = {
-    'matplotlib': [],
-}
-
-
-def blacklist_check(path):
-    """Check if test is blacklisted and should be ignored"""
-    head, tests_dir = os.path.split(path.dirname)
-    if tests_dir != 'tests':
-        return True
-    head, top_module = os.path.split(head)
-    return path.purebasename in IGNORED_TESTS.get(top_module, [])
-
-
-def whitelist_check(path):
-    """Check if test is not whitelisted and should be ignored"""
-    left = path.dirname
-    last_left = None
-    module_path = path.purebasename
-    while len(left) and left != last_left:
-        last_left = left
-        left, tail = os.path.split(left)
-        module_path = '.'.join([tail, module_path])
-        if module_path in default_test_modules:
-            return False
-    return True
-
-
-COLLECT_FILTERS = {
-    'none': lambda _: False,
-    'blacklist': blacklist_check,
-    'whitelist': whitelist_check,
-}
-
-
-def pytest_addoption(parser):
-    group = parser.getgroup("matplotlib", "matplotlib custom options")
-
-    group.addoption('--collect-filter', action='store',
-                    choices=COLLECT_FILTERS, default='blacklist',
-                    help='filter tests during collection phase')
-
-    group.addoption('--no-pep8', action='store_true',
-                    help='skip PEP8 compliance tests')
-
 
 def pytest_configure(config):
     matplotlib._called_from_pytest = True
     matplotlib._init_tests()
 
-    if config.getoption('--no-pep8'):
-        IGNORED_TESTS['matplotlib'] += 'test_coding_standards'
-
 
 def pytest_unconfigure(config):
     matplotlib._called_from_pytest = False
-
-
-def pytest_ignore_collect(path, config):
-    if path.ext == '.py':
-        collect_filter = config.getoption('--collect-filter')
-        return COLLECT_FILTERS[collect_filter](path)

pytest.ini

@@ -1,5 +1,6 @@
 [pytest]
-norecursedirs = .git build ci dist extern release tools unit venv
+norecursedirs = .git build ci dist doc extern lib/mpl_examples release tools unit venv
+python_files = test_*.py
 pep8ignore =
     * E111 E114 E115 E116 E121 E122 E123 E124 E125 E126 E127 E128 E129 E131 E226 E240 E241 E242 E243 E244 E245 E246 E247 E248 E249 E265 E266 E704 W503
 

tests.py

@@ -22,13 +22,13 @@
 
     # The warnings need to be before any of matplotlib imports, but after
     # setuptools (if present) which has syntax error with the warnings enabled.
-    # Filtering by module does not work as this will be raised by Python itself.
+    # Filtering by module does not work as this will be raised by Python itself
     # so `module=matplotlib.*` is out of questions.
 
     import warnings
 
-    # Python 3.6 deprecate invalid character-pairs \A, \* ... in non raw-strings
-    # and other things. Let's not re-introduce them
+    # Python 3.6 deprecate invalid character-pairs \A, \* ... in non
+    # raw-strings and other things. Let's not re-introduce them
     warnings.filterwarnings('error', '.*invalid escape sequence.*',
         category=DeprecationWarning)
     warnings.filterwarnings(