• Issue #31855: unittest.mock.mock_open() results now respects the argument of read([size]). Patch contributed by Rémi Lapeyre.


  • Include the license, readme and changelog in the source distribution.


  • Fixed patching of dictionaries, when specifying the target with a unicode on Python 2.


  • Add missing funcsigs dependency on Python 2.


  • Fix packaging issue where six was missed as a dependency.


  • Issue #35226: Recursively check arguments when testing for equality of objects and add note that tracking of parameters used to create ancestors of mocks in mock_calls is not possible.

  • Issue #31177: Fix bug that prevented using reset_mock on mock instances with deleted attributes

  • Issue #26704: Added test demonstrating double-patching of an instance method. Patch by Anthony Sottile.

  • Issue #35500: Write expected and actual call parameters on separate lines in unittest.mock.Mock.assert_called_with() assertion errors. Contributed by Susan Su.

  • Issue #35330: When a Mock instance was used to wrap an object, if side_effect is used in one of the mocks of it methods, don’t call the original implementation and return the result of using the side effect the same way that it is done with return_value.

  • Issue #30541: Add new function to seal a mock and prevent the automatically creation of child mocks. Patch by Mario Corchero.

  • Issue #35022: unittest.mock.MagicMock now supports the __fspath__ method (from os.PathLike).

  • Issue #33516: unittest.mock.MagicMock now supports the __round__ magic method.

  • Issue #35512: unittest.mock.patch.dict() used as a decorator with string target resolves the target during function call instead of during decorator construction. Patch by Karthikeyan Singaravelan.

  • Issue #36366: Calling stop() on an unstarted or stopped unittest.mock.patch() object will now return None instead of raising RuntimeError, making the method idempotent. Patch byKarthikeyan Singaravelan.

  • Issue #35357: Internal attributes’ names of unittest.mock._Call and unittest.mock.MagicProxy (name, parent & from_kall) are now prefixed with _mock_ in order to prevent clashes with widely used object attributes. Fixed minor typo in test function name.

  • Issue #20239: Allow repeated assignment deletion of unittest.mock.Mock attributes. Patch by Pablo Galindo.

  • Issue #35082: Don’t return deleted attributes when calling dir on a unittest.mock.Mock.

  • Issue #0: Improved an error message when mock assert_has_calls fails.

  • Issue #23078: Add support for classmethod() and staticmethod() to unittest.mock.create_autospec(). Initial patch by Felipe Ochoa.

  • Issue #21478: Calls to a child function created with unittest.mock.create_autospec() should propagate to the parent. Patch by Karthikeyan Singaravelan.

  • Issue #36598: Fix isinstance check for Mock objects with spec when the code is executed under tracing. Patch by Karthikeyan Singaravelan.

  • Issue #32933: unittest.mock.mock_open() now supports iteration over the file contents. Patch by Tony Flury.

  • Issue #21269: Add args and kwargs properties to mock call objects. Contributed by Kumar Akshay.

  • Issue #17185: Set __signature__ on mock for inspect to get signature. Patch by Karthikeyan Singaravelan.

  • Issue #35047: unittest.mock now includes mock calls in exception messages if assert_not_called, assert_called_once, or assert_called_once_with fails. Patch by Petter Strandmark.

  • Issue #28380: unittest.mock Mock autospec functions now properly support assert_called, assert_not_called, and assert_called_once.

  • Issue #28735: Fixed the comparison of mock.MagickMock with mock.ANY.

  • Issue #20804: The unittest.mock.sentinel attributes now preserve their identity when they are copied or pickled.

  • Issue #28961: Fix unittest.mock._Call helper: don’t ignore the name parameter anymore. Patch written by Jiajun Huang.

  • Issue #26750: unittest.mock.create_autospec() now works properly for subclasses of property() and other data descriptors.

  • Issue #21271: New keyword only parameters in reset_mock call.

  • Issue #26807: mock_open ‘files’ no longer error on readline at end of file. Patch from Yolanda Robla.

  • Issue #25195: Fix a regression in mock.MagicMock. _Call is a subclass of tuple (changeset 3603bae63c13 only works for classes) so we need to implement __ne__ ourselves. Patch by Andrew Plummer.

2.0.0 and earlier

  • Issue #26323: Add Mock.assert_called() and Mock.assert_called_once() methods to unittest.mock. Patch written by Amit Saha.

  • Issue #22138: Fix mock.patch behavior when patching descriptors. Restore original values after patching. Patch contributed by Sean McCully.

  • Issue #24857: Comparing call_args to a long sequence now correctly returns a boolean result instead of raising an exception. Patch by A Kaptur.

  • Issue #23004: mock_open() now reads binary data correctly when the type of read_data is bytes. Initial patch by Aaron Hill.

  • Issue #21750: mock_open.read_data can now be read from each instance, as it could in Python 3.3.

  • Issue #18622: unittest.mock.mock_open().reset_mock would recurse infinitely. Patch from Nicola Palumbo and Laurent De Buyst.

  • Issue #23661: unittest.mock side_effects can now be exceptions again. This was a regression vs Python 3.4. Patch from Ignacio Rossi

  • Issue #23310: Fix MagicMock’s initializer to work with __methods__, just like configure_mock(). Patch by Kasia Jachim.

  • Issue #23568: Add rdivmod support to MagicMock() objects. Patch by Håkan Lövdahl.

  • Issue #23581: Add matmul support to MagicMock. Patch by Håkan Lövdahl.

  • Issue #23326: Removed __ne__ implementations. Since fixing default __ne__ implementation in issue #21408 they are redundant. * NOT BACKPORTED *

  • Issue #21270: We now override tuple methods in objects so that they can be used as normal call attributes.

  • Issue #21256: Printout of keyword args should be in deterministic order in a mock function call. This will help to write better doctests.

  • Issue #21262: New method assert_not_called for Mock. It raises AssertionError if the mock has been called.

  • Issue #21238: New keyword argument unsafe to Mock. It raises AttributeError incase of an attribute startswith assert or assret.

  • Issue #21239: patch.stopall() didn’t work deterministically when the same name was patched more than once.

  • Issue #21222: Passing name keyword argument to mock.create_autospec now works.

  • Issue #17826: setting an iterable side_effect on a mock function created by create_autospec now works. Patch by Kushal Das.

  • Issue #17826: setting an iterable side_effect on a mock function created by create_autospec now works. Patch by Kushal Das.

  • Issue #20968: unittest.mock.MagicMock now supports division. Patch by Johannes Baiter.

  • Issue #20189: unittest.mock now no longer assumes that any object for which it could get an inspect.Signature is a callable written in Python. Fix courtesy of Michael Foord.

  • Issue #17467: add readline and readlines support to mock_open in unittest.mock.

  • Issue #17015: When it has a spec, a Mock object now inspects its signature when matching calls, so that arguments can be matched positionally or by name.

  • Issue #15323: improve failure message of Mock.assert_called_once_with

  • Issue #14857: fix regression in references to PEP 3135 implicit __class__ closure variable (Reopens issue #12370)

  • Issue #14295: Add unittest.mock