Reviewed: https://review.openstack.org/524438 Committed: https://git.openstack.org/cgit/openstack/oslotest/commit/?id=0bde35899a10875891f0592961c01e9fbb854738 Submitter: Zuul Branch: master
commit 0bde35899a10875891f0592961c01e9fbb854738 Author: Claudiu Belu <[email protected]> Date: Fri Dec 1 03:24:14 2017 +0200 Adds mock autospec fixture In typical unit tests, almost all of the dependencies are mocked or patched (mock.patch), without any guarantee that the mocked methods actually exist, or if their signatures are respected (see below). Because of this, actual issues can easily be overlooked and missed, as the unit tests are wrongfully passing. The mock.Mock class accepts a spec as an argument, which only solves half the problem: it only checks if an attribute exists, based on the given spec. It does not guarantee that the given attribute is actually a method, or if its signature is respected. Some unit tests may pass the autospec argument, but mock doesn't support it at the moment. mock.patch, mock.patch.object, mock.patch.multiple accept an autospec argument, but because of a bug, it cannot be used properly. Adds a fixture which replaces mock.Mock and mock.MagicMock with subclass which accepts the autospec argument, and on call, it will check the signature of the called method / function. Adds a function which replaces mock.mock._patch with a subclass, which treats the autospec argument properly (consumes the self / cls argument), and sets autospec=True by default, unless otherwise specified. WARNING: this function is not a fixture, and in order to benefit from it, it will have to be called as EARLY as possible, before any test classes are loaded, otherwise the original mock.mock._patch is used instead. Needed-By: I3636833962c905faa0f144c7fdc4833037324d31 Needed-By: I4484e63c97bd1cdde3d88855eabe7545784f365e Closes-Bug: #1735588 Change-Id: I0e4a55fbf4c1d175726ca22b664e240849a99856 ** Changed in: oslotest Status: In Progress => Fix Released -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to OpenStack Compute (nova). https://bugs.launchpad.net/bugs/1735588 Title: Mock autospec not used, or not used properly Status in networking-hyperv: New Status in OpenStack Compute (nova): In Progress Status in os-win: New Status in oslotest: Fix Released Bug description: Description =========== In typical unit tests, almost all of the dependencies are mocked or patched (mock.patch), without any guarantee that the mocked methods actually exist, or if their signatures are respected (see below). Because of this, actual issues can easily be overlooked and missed, as the unit tests are wrongfully passing. [0] The mock.Mock class accepts a spec as an argument, which only solves half the problem: it only checks if an attribute exists, based on the given spec. It does not guarantee that the given attribute is actually a method, or if its signature is respected [1][2]. Some unit tests may pass the autospec argument, but mock doesn't support it at the moment. mock.patch, mock.patch.object, mock.patch.multiple accept an autospec argument, but because of a bug [3][4], it cannot be used properly. Steps to reproduce ================== import mock from mock.tests import testmock m = mock.Mock(spec=testmock.Something) # meth has the following signature: # def meth(self, a, b, c, d=None): m.meth() Expected result =============== TypeError should be raised. Actual result ============= A mock object is returned. Proposal ======== Bug reports have been issues for the bugs mentioned above, see [1][2][3][4], but until then, the mock library can be patched to include the following changes: - add autospec argument to mock.Mock and mock.MagicMock. Unit test should then pass the autospec argument whenever possible. - fix the mock.patch autospec issue. - enable mock.patch autospec by default, unless otherwise specified. Links ===== [0] https://review.openstack.org/#/c/461689/ [1] https://github.com/testing-cabal/mock/issues/393 [2] https://bugs.python.org/issue30587 [3] https://github.com/testing-cabal/mock/issues/396 [4] https://bugs.python.org/issue32092 To manage notifications about this bug go to: https://bugs.launchpad.net/networking-hyperv/+bug/1735588/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : [email protected] Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp
