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diff --git a/python/mock-1.0.0/docs/compare.txt b/python/mock-1.0.0/docs/compare.txt new file mode 100644 index 000000000..41555308e --- /dev/null +++ b/python/mock-1.0.0/docs/compare.txt @@ -0,0 +1,628 @@ +========================= + Mock Library Comparison +========================= + + +.. testsetup:: + + def assertEqual(a, b): + assert a == b, ("%r != %r" % (a, b)) + + def assertRaises(Exc, func): + try: + func() + except Exc: + return + assert False, ("%s not raised" % Exc) + + sys.modules['somemodule'] = somemodule = mock.Mock(name='somemodule') + class SomeException(Exception): + some_method = method1 = method2 = None + some_other_object = SomeObject = SomeException + + +A side-by-side comparison of how to accomplish some basic tasks with mock and +some other popular Python mocking libraries and frameworks. + +These are: + +* `flexmock <http://pypi.python.org/pypi/flexmock>`_ +* `mox <http://pypi.python.org/pypi/mox>`_ +* `Mocker <http://niemeyer.net/mocker>`_ +* `dingus <http://pypi.python.org/pypi/dingus>`_ +* `fudge <http://pypi.python.org/pypi/fudge>`_ + +Popular python mocking frameworks not yet represented here include +`MiniMock <http://pypi.python.org/pypi/MiniMock>`_. + +`pMock <http://pmock.sourceforge.net/>`_ (last release 2004 and doesn't import +in recent versions of Python) and +`python-mock <http://python-mock.sourceforge.net/>`_ (last release 2005) are +intentionally omitted. + +.. note:: + + A more up to date, and tested for all mock libraries (only the mock + examples on this page can be executed as doctests) version of this + comparison is maintained by Gary Bernhardt: + + * `Python Mock Library Comparison + <http://garybernhardt.github.com/python-mock-comparison/>`_ + +This comparison is by no means complete, and also may not be fully idiomatic +for all the libraries represented. *Please* contribute corrections, missing +comparisons, or comparisons for additional libraries to the `mock issue +tracker <https://code.google.com/p/mock/issues/list>`_. + +This comparison page was originally created by the `Mox project +<https://code.google.com/p/pymox/wiki/MoxComparison>`_ and then extended for +`flexmock and mock <http://has207.github.com/flexmock/compare.html>`_ by +Herman Sheremetyev. Dingus examples written by `Gary Bernhadt +<http://garybernhardt.github.com/python-mock-comparison/>`_. fudge examples +provided by `Kumar McMillan <http://farmdev.com/>`_. + +.. note:: + + The examples tasks here were originally created by Mox which is a mocking + *framework* rather than a library like mock. The tasks shown naturally + exemplify tasks that frameworks are good at and not the ones they make + harder. In particular you can take a `Mock` or `MagicMock` object and use + it in any way you want with no up-front configuration. The same is also + true for Dingus. + + The examples for mock here assume version 0.7.0. + + +Simple fake object +~~~~~~~~~~~~~~~~~~ + +.. doctest:: + + >>> # mock + >>> my_mock = mock.Mock() + >>> my_mock.some_method.return_value = "calculated value" + >>> my_mock.some_attribute = "value" + >>> assertEqual("calculated value", my_mock.some_method()) + >>> assertEqual("value", my_mock.some_attribute) + +:: + + # Flexmock + mock = flexmock(some_method=lambda: "calculated value", some_attribute="value") + assertEqual("calculated value", mock.some_method()) + assertEqual("value", mock.some_attribute) + + # Mox + mock = mox.MockAnything() + mock.some_method().AndReturn("calculated value") + mock.some_attribute = "value" + mox.Replay(mock) + assertEqual("calculated value", mock.some_method()) + assertEqual("value", mock.some_attribute) + + # Mocker + mock = mocker.mock() + mock.some_method() + mocker.result("calculated value") + mocker.replay() + mock.some_attribute = "value" + assertEqual("calculated value", mock.some_method()) + assertEqual("value", mock.some_attribute) + +:: + + >>> # Dingus + >>> my_dingus = dingus.Dingus(some_attribute="value", + ... some_method__returns="calculated value") + >>> assertEqual("calculated value", my_dingus.some_method()) + >>> assertEqual("value", my_dingus.some_attribute) + +:: + + >>> # fudge + >>> my_fake = (fudge.Fake() + ... .provides('some_method') + ... .returns("calculated value") + ... .has_attr(some_attribute="value")) + ... + >>> assertEqual("calculated value", my_fake.some_method()) + >>> assertEqual("value", my_fake.some_attribute) + + +Simple mock +~~~~~~~~~~~ + +.. doctest:: + + >>> # mock + >>> my_mock = mock.Mock() + >>> my_mock.some_method.return_value = "value" + >>> assertEqual("value", my_mock.some_method()) + >>> my_mock.some_method.assert_called_once_with() + +:: + + # Flexmock + mock = flexmock() + mock.should_receive("some_method").and_return("value").once + assertEqual("value", mock.some_method()) + + # Mox + mock = mox.MockAnything() + mock.some_method().AndReturn("value") + mox.Replay(mock) + assertEqual("value", mock.some_method()) + mox.Verify(mock) + + # Mocker + mock = mocker.mock() + mock.some_method() + mocker.result("value") + mocker.replay() + assertEqual("value", mock.some_method()) + mocker.verify() + +:: + + >>> # Dingus + >>> my_dingus = dingus.Dingus(some_method__returns="value") + >>> assertEqual("value", my_dingus.some_method()) + >>> assert my_dingus.some_method.calls().once() + +:: + + >>> # fudge + >>> @fudge.test + ... def test(): + ... my_fake = (fudge.Fake() + ... .expects('some_method') + ... .returns("value") + ... .times_called(1)) + ... + >>> test() + Traceback (most recent call last): + ... + AssertionError: fake:my_fake.some_method() was not called + + +Creating partial mocks +~~~~~~~~~~~~~~~~~~~~~~ + +.. doctest:: + + >>> # mock + >>> SomeObject.some_method = mock.Mock(return_value='value') + >>> assertEqual("value", SomeObject.some_method()) + +:: + + # Flexmock + flexmock(SomeObject).should_receive("some_method").and_return('value') + assertEqual("value", mock.some_method()) + + # Mox + mock = mox.MockObject(SomeObject) + mock.some_method().AndReturn("value") + mox.Replay(mock) + assertEqual("value", mock.some_method()) + mox.Verify(mock) + + # Mocker + mock = mocker.mock(SomeObject) + mock.Get() + mocker.result("value") + mocker.replay() + assertEqual("value", mock.some_method()) + mocker.verify() + +:: + + >>> # Dingus + >>> object = SomeObject + >>> object.some_method = dingus.Dingus(return_value="value") + >>> assertEqual("value", object.some_method()) + +:: + + >>> # fudge + >>> fake = fudge.Fake().is_callable().returns("<fudge-value>") + >>> with fudge.patched_context(SomeObject, 'some_method', fake): + ... s = SomeObject() + ... assertEqual("<fudge-value>", s.some_method()) + ... + + +Ensure calls are made in specific order +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +.. doctest:: + + >>> # mock + >>> my_mock = mock.Mock(spec=SomeObject) + >>> my_mock.method1() + <Mock name='mock.method1()' id='...'> + >>> my_mock.method2() + <Mock name='mock.method2()' id='...'> + >>> assertEqual(my_mock.mock_calls, [call.method1(), call.method2()]) + +:: + + # Flexmock + mock = flexmock(SomeObject) + mock.should_receive('method1').once.ordered.and_return('first thing') + mock.should_receive('method2').once.ordered.and_return('second thing') + + # Mox + mock = mox.MockObject(SomeObject) + mock.method1().AndReturn('first thing') + mock.method2().AndReturn('second thing') + mox.Replay(mock) + mox.Verify(mock) + + # Mocker + mock = mocker.mock() + with mocker.order(): + mock.method1() + mocker.result('first thing') + mock.method2() + mocker.result('second thing') + mocker.replay() + mocker.verify() + +:: + + >>> # Dingus + >>> my_dingus = dingus.Dingus() + >>> my_dingus.method1() + <Dingus ...> + >>> my_dingus.method2() + <Dingus ...> + >>> assertEqual(['method1', 'method2'], [call.name for call in my_dingus.calls]) + +:: + + >>> # fudge + >>> @fudge.test + ... def test(): + ... my_fake = (fudge.Fake() + ... .remember_order() + ... .expects('method1') + ... .expects('method2')) + ... my_fake.method2() + ... my_fake.method1() + ... + >>> test() + Traceback (most recent call last): + ... + AssertionError: Call #1 was fake:my_fake.method2(); Expected: #1 fake:my_fake.method1(), #2 fake:my_fake.method2(), end + + +Raising exceptions +~~~~~~~~~~~~~~~~~~ + +.. doctest:: + + >>> # mock + >>> my_mock = mock.Mock() + >>> my_mock.some_method.side_effect = SomeException("message") + >>> assertRaises(SomeException, my_mock.some_method) + +:: + + # Flexmock + mock = flexmock() + mock.should_receive("some_method").and_raise(SomeException("message")) + assertRaises(SomeException, mock.some_method) + + # Mox + mock = mox.MockAnything() + mock.some_method().AndRaise(SomeException("message")) + mox.Replay(mock) + assertRaises(SomeException, mock.some_method) + mox.Verify(mock) + + # Mocker + mock = mocker.mock() + mock.some_method() + mocker.throw(SomeException("message")) + mocker.replay() + assertRaises(SomeException, mock.some_method) + mocker.verify() + +:: + + >>> # Dingus + >>> my_dingus = dingus.Dingus() + >>> my_dingus.some_method = dingus.exception_raiser(SomeException) + >>> assertRaises(SomeException, my_dingus.some_method) + +:: + + >>> # fudge + >>> my_fake = (fudge.Fake() + ... .is_callable() + ... .raises(SomeException("message"))) + ... + >>> my_fake() + Traceback (most recent call last): + ... + SomeException: message + + +Override new instances of a class +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +.. doctest:: + + >>> # mock + >>> with mock.patch('somemodule.Someclass') as MockClass: + ... MockClass.return_value = some_other_object + ... assertEqual(some_other_object, somemodule.Someclass()) + ... + + +:: + + # Flexmock + flexmock(some_module.SomeClass, new_instances=some_other_object) + assertEqual(some_other_object, some_module.SomeClass()) + + # Mox + # (you will probably have mox.Mox() available as self.mox in a real test) + mox.Mox().StubOutWithMock(some_module, 'SomeClass', use_mock_anything=True) + some_module.SomeClass().AndReturn(some_other_object) + mox.ReplayAll() + assertEqual(some_other_object, some_module.SomeClass()) + + # Mocker + instance = mocker.mock() + klass = mocker.replace(SomeClass, spec=None) + klass('expected', 'args') + mocker.result(instance) + +:: + + >>> # Dingus + >>> MockClass = dingus.Dingus(return_value=some_other_object) + >>> with dingus.patch('somemodule.SomeClass', MockClass): + ... assertEqual(some_other_object, somemodule.SomeClass()) + ... + +:: + + >>> # fudge + >>> @fudge.patch('somemodule.SomeClass') + ... def test(FakeClass): + ... FakeClass.is_callable().returns(some_other_object) + ... assertEqual(some_other_object, somemodule.SomeClass()) + ... + >>> test() + + +Call the same method multiple times +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +.. note:: + + You don't need to do *any* configuration to call `mock.Mock()` methods + multiple times. Attributes like `call_count`, `call_args_list` and + `method_calls` provide various different ways of making assertions about + how the mock was used. + +.. doctest:: + + >>> # mock + >>> my_mock = mock.Mock() + >>> my_mock.some_method() + <Mock name='mock.some_method()' id='...'> + >>> my_mock.some_method() + <Mock name='mock.some_method()' id='...'> + >>> assert my_mock.some_method.call_count >= 2 + +:: + + # Flexmock # (verifies that the method gets called at least twice) + flexmock(some_object).should_receive('some_method').at_least.twice + + # Mox + # (does not support variable number of calls, so you need to create a new entry for each explicit call) + mock = mox.MockObject(some_object) + mock.some_method(mox.IgnoreArg(), mox.IgnoreArg()) + mock.some_method(mox.IgnoreArg(), mox.IgnoreArg()) + mox.Replay(mock) + mox.Verify(mock) + + # Mocker + # (TODO) + +:: + + >>> # Dingus + >>> my_dingus = dingus.Dingus() + >>> my_dingus.some_method() + <Dingus ...> + >>> my_dingus.some_method() + <Dingus ...> + >>> assert len(my_dingus.calls('some_method')) == 2 + +:: + + >>> # fudge + >>> @fudge.test + ... def test(): + ... my_fake = fudge.Fake().expects('some_method').times_called(2) + ... my_fake.some_method() + ... + >>> test() + Traceback (most recent call last): + ... + AssertionError: fake:my_fake.some_method() was called 1 time(s). Expected 2. + + +Mock chained methods +~~~~~~~~~~~~~~~~~~~~ + +.. doctest:: + + >>> # mock + >>> my_mock = mock.Mock() + >>> method3 = my_mock.method1.return_value.method2.return_value.method3 + >>> method3.return_value = 'some value' + >>> assertEqual('some value', my_mock.method1().method2().method3(1, 2)) + >>> method3.assert_called_once_with(1, 2) + +:: + + # Flexmock + # (intermediate method calls are automatically assigned to temporary fake objects + # and can be called with any arguments) + flexmock(some_object).should_receive( + 'method1.method2.method3' + ).with_args(arg1, arg2).and_return('some value') + assertEqual('some_value', some_object.method1().method2().method3(arg1, arg2)) + +:: + + # Mox + mock = mox.MockObject(some_object) + mock2 = mox.MockAnything() + mock3 = mox.MockAnything() + mock.method1().AndReturn(mock1) + mock2.method2().AndReturn(mock2) + mock3.method3(arg1, arg2).AndReturn('some_value') + self.mox.ReplayAll() + assertEqual("some_value", some_object.method1().method2().method3(arg1, arg2)) + self.mox.VerifyAll() + + # Mocker + # (TODO) + +:: + + >>> # Dingus + >>> my_dingus = dingus.Dingus() + >>> method3 = my_dingus.method1.return_value.method2.return_value.method3 + >>> method3.return_value = 'some value' + >>> assertEqual('some value', my_dingus.method1().method2().method3(1, 2)) + >>> assert method3.calls('()', 1, 2).once() + +:: + + >>> # fudge + >>> @fudge.test + ... def test(): + ... my_fake = fudge.Fake() + ... (my_fake + ... .expects('method1') + ... .returns_fake() + ... .expects('method2') + ... .returns_fake() + ... .expects('method3') + ... .with_args(1, 2) + ... .returns('some value')) + ... assertEqual('some value', my_fake.method1().method2().method3(1, 2)) + ... + >>> test() + + +Mocking a context manager +~~~~~~~~~~~~~~~~~~~~~~~~~ + +Examples for mock, Dingus and fudge only (so far): + +.. doctest:: + + >>> # mock + >>> my_mock = mock.MagicMock() + >>> with my_mock: + ... pass + ... + >>> my_mock.__enter__.assert_called_with() + >>> my_mock.__exit__.assert_called_with(None, None, None) + +:: + + + >>> # Dingus (nothing special here; all dinguses are "magic mocks") + >>> my_dingus = dingus.Dingus() + >>> with my_dingus: + ... pass + ... + >>> assert my_dingus.__enter__.calls() + >>> assert my_dingus.__exit__.calls('()', None, None, None) + +:: + + >>> # fudge + >>> my_fake = fudge.Fake().provides('__enter__').provides('__exit__') + >>> with my_fake: + ... pass + ... + + +Mocking the builtin open used as a context manager +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Example for mock only (so far): + +.. doctest:: + + >>> # mock + >>> my_mock = mock.MagicMock() + >>> with mock.patch('__builtin__.open', my_mock): + ... manager = my_mock.return_value.__enter__.return_value + ... manager.read.return_value = 'some data' + ... with open('foo') as h: + ... data = h.read() + ... + >>> data + 'some data' + >>> my_mock.assert_called_once_with('foo') + +*or*: + +.. doctest:: + + >>> # mock + >>> with mock.patch('__builtin__.open') as my_mock: + ... my_mock.return_value.__enter__ = lambda s: s + ... my_mock.return_value.__exit__ = mock.Mock() + ... my_mock.return_value.read.return_value = 'some data' + ... with open('foo') as h: + ... data = h.read() + ... + >>> data + 'some data' + >>> my_mock.assert_called_once_with('foo') + +:: + + >>> # Dingus + >>> my_dingus = dingus.Dingus() + >>> with dingus.patch('__builtin__.open', my_dingus): + ... file_ = open.return_value.__enter__.return_value + ... file_.read.return_value = 'some data' + ... with open('foo') as h: + ... data = f.read() + ... + >>> data + 'some data' + >>> assert my_dingus.calls('()', 'foo').once() + +:: + + >>> # fudge + >>> from contextlib import contextmanager + >>> from StringIO import StringIO + >>> @contextmanager + ... def fake_file(filename): + ... yield StringIO('sekrets') + ... + >>> with fudge.patch('__builtin__.open') as fake_open: + ... fake_open.is_callable().calls(fake_file) + ... with open('/etc/password') as f: + ... data = f.read() + ... + fake:__builtin__.open + >>> data + 'sekrets'
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