Commit d3fdaf90 authored by Tommy Beadle's avatar Tommy Beadle Committed by Tim Graham
Browse files

Fixed #23727 -- Inhibited the post_migrate signal when using serialized_rollback. 

When using a TransactionTestCase with serialized_rollback=True,
after creating the database and running its migrations (along with
emitting the post_migrate signal), the contents of the database
are serialized to _test_serialized_contents.

After the first test case, _fixture_teardown() would flush the
tables but then the post_migrate signal would be emitted and new
rows (with new PKs) would be created in the django_content_type
table. Then in any subsequent test cases in a suite,
_fixture_setup() attempts to deserialize the content of
 _test_serialized_contents, but these rows are identical to the
rows already in the database except for their PKs.  This causes an
IntegrityError due to the unique constraint in the
django_content_type table.

This change made it so that in the above scenario the post_migrate
signal is not emitted after flushing the tables, since it will be
repopulated during fixture_setup().
parent 45ed19de

AUTHORS

+1 −0
Original line number Diff line number Diff line
@@ -698,6 +698,7 @@ answer newbie questions, and generally made Django that much better: 
    Tome Cvitan <tome@cvitan.com>

    Tomek Paczkowski <tomek@hauru.eu>

    Tom Insam

    Tommy Beadle <tbeadle@gmail.com>

    Tom Tobin

    torne-django@wolfpuppy.org.uk

    Travis Cline <travis.cline@gmail.com>

django/test/testcases.py

+10 −1
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@@ -940,10 +940,19 @@ class TransactionTestCase(SimpleTestCase): 
        # when flushing only a subset of the apps

        for db_name in self._databases_names(include_mirrors=False):

            # Flush the database

            inhibit_post_migrate = (

                self.available_apps is not None

                or (

                    # Inhibit the post_migrate signal when using serialized

                    # rollback to avoid trying to recreate the serialized data.

                    self.serialized_rollback and

                    hasattr(connections[db_name], '_test_serialized_contents')

                )

            )

            call_command('flush', verbosity=0, interactive=False,

                         database=db_name, reset_sequences=False,

                         allow_cascade=self.available_apps is not None,

                         inhibit_post_migrate=self.available_apps is not None)

                         inhibit_post_migrate=inhibit_post_migrate)



    def assertQuerysetEqual(self, qs, values, transform=repr, ordered=True, msg=None):

        items = six.moves.map(transform, qs)

docs/topics/testing/overview.txt

+7 −0
Original line number Diff line number Diff line
@@ -250,6 +250,13 @@ The initial serialization is usually very quick, but if you wish to exclude 
some apps from this process (and speed up test runs slightly), you may add

those apps to :setting:`TEST_NON_SERIALIZED_APPS`.



.. versionchanged:: 1.9



To prevent serialized data from being loaded twice, setting

``serialized_rollback=True`` disables the

:data:`~django.db.models.signals.post_migrate` signal when flushing the test

database.



Other test conditions

---------------------

tests/test_utils/test_transactiontestcase.py

0 → 100644
+28 −0
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from django.test import TransactionTestCase, mock





class TestSerializedRollbackInhibitsPostMigrate(TransactionTestCase):

    """

    TransactionTestCase._fixture_teardown() inhibits the post_migrate signal

    for test classes with serialized_rollback=True.

    """

    available_apps = ['test_utils']

    serialized_rollback = True



    def setUp(self):

        # self.available_apps must be None to test the serialized_rollback

        # condition.

        self.available_apps = None



    def tearDown(self):

        self.available_apps = ['test_utils']



    @mock.patch('django.test.testcases.call_command')

    def test(self, call_command):

        # with a mocked call_command(), this doesn't have any effect.

        self._fixture_teardown()

        call_command.assert_called_with(

            'flush', interactive=False, allow_cascade=False,

            reset_sequences=False, inhibit_post_migrate=True,

            database='default', verbosity=0,

        )