Added --no-pep8 key for pytest

Author: Kojoley

conftest.py

@@ -63,11 +63,18 @@ def pytest_addoption(parser):
                     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'):
+        default_test_modules.remove('matplotlib.tests.test_coding_standards')
+        IGNORED_TESTS['matplotlib'] += 'test_coding_standards'
+
 
 def pytest_unconfigure(config):
     matplotlib._called_from_pytest = False