Add pytest-django-ordering

This awesome plugin handles the same test sorting as our local conftest module. We can apply this plugin to other projects requiring the same treatment.

course_discovery/apps/conftest.py

-"""Directory-specific hook implementations for pytest."""
-from django.test import TestCase, TransactionTestCase
-
-
-def pytest_collection_modifyitems(items):
-    def weight_test_case(test):
-        """
-        The default Django test runner gives priority to TestCase subclasses,
-        executing them before all Django-based tests (e.g., TransactionTestCase)
-        and any other unittest.TestCase tests; see
-        https://docs.djangoproject.com/en/1.9/topics/testing/overview/#order-in-which-tests-are-executed.
-
-        pytest-django doesn't preserve this ordering out of the box. For more on
-        this, see https://github.com/pytest-dev/pytest-django/issues/214.
-
-        This isn't a problem if your project's tests can run independently of each
-        other, in any order. Sadly, the majority of this project's tests rely on
-        initial data populated via migrations, which means that TestCase subclasses
-        *must* run before TransactionTestCase subclasses which reset the database
-        by truncating all tables, deleting any initial data. (The serialized_rollback
-        option can be used to remedy this within a given TransactionTestCase, but
-        it has no effect across distinct test cases; once you exit a TransactionTestCase,
-        any initial data is gone.)
-        """
-        # Test are not necessarily methods; they can be functions, in which case
-        # there is no associated class.
-        if test.cls:
-            # If the test is a subclass of TestCase, we want to run it early.
-            if issubclass(test.cls, TestCase):
-                return 0
-            # If the test is a subclass of TransactionTestCase, we want to run it last.
-            elif issubclass(test.cls, TransactionTestCase):
-                return 1
-            # If the test is a subclass of some other class, let it run with TestCases.
-            else:
-                return 0
-
-        return 0
-
-    items.sort(key=weight_test_case)

requirements/test.txt

@@ -11,6 +11,7 @@ mock==2.0.0
 pep8==1.7.0
 pytest==3.0.6
 pytest-django==3.1.2
+pytest-django-ordering==1.0.1
 responses==0.5.1
 selenium==3.0.2
 testfixtures==4.13.1