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diff --git a/third_party/py/mock/html/_sources/magicmock.txt b/third_party/py/mock/html/_sources/magicmock.txt new file mode 100644 index 0000000000..42b2ed9db1 --- /dev/null +++ b/third_party/py/mock/html/_sources/magicmock.txt @@ -0,0 +1,258 @@ + +.. currentmodule:: mock + + +.. _magic-methods: + +Mocking Magic Methods +===================== + +.. currentmodule:: mock + +:class:`Mock` supports mocking `magic methods +<http://www.ironpythoninaction.com/magic-methods.html>`_. This allows mock +objects to replace containers or other objects that implement Python +protocols. + +Because magic methods are looked up differently from normal methods [#]_, this +support has been specially implemented. This means that only specific magic +methods are supported. The supported list includes *almost* all of them. If +there are any missing that you need please let us know! + +You mock magic methods by setting the method you are interested in to a function +or a mock instance. If you are using a function then it *must* take ``self`` as +the first argument [#]_. + +.. doctest:: + + >>> def __str__(self): + ... return 'fooble' + ... + >>> mock = Mock() + >>> mock.__str__ = __str__ + >>> str(mock) + 'fooble' + + >>> mock = Mock() + >>> mock.__str__ = Mock() + >>> mock.__str__.return_value = 'fooble' + >>> str(mock) + 'fooble' + + >>> mock = Mock() + >>> mock.__iter__ = Mock(return_value=iter([])) + >>> list(mock) + [] + +One use case for this is for mocking objects used as context managers in a +`with` statement: + +.. doctest:: + + >>> mock = Mock() + >>> mock.__enter__ = Mock(return_value='foo') + >>> mock.__exit__ = Mock(return_value=False) + >>> with mock as m: + ... assert m == 'foo' + ... + >>> mock.__enter__.assert_called_with() + >>> mock.__exit__.assert_called_with(None, None, None) + +Calls to magic methods do not appear in :attr:`~Mock.method_calls`, but they +are recorded in :attr:`~Mock.mock_calls`. + +.. note:: + + If you use the `spec` keyword argument to create a mock then attempting to + set a magic method that isn't in the spec will raise an `AttributeError`. + +The full list of supported magic methods is: + +* ``__hash__``, ``__sizeof__``, ``__repr__`` and ``__str__`` +* ``__dir__``, ``__format__`` and ``__subclasses__`` +* ``__floor__``, ``__trunc__`` and ``__ceil__`` +* Comparisons: ``__cmp__``, ``__lt__``, ``__gt__``, ``__le__``, ``__ge__``, + ``__eq__`` and ``__ne__`` +* Container methods: ``__getitem__``, ``__setitem__``, ``__delitem__``, + ``__contains__``, ``__len__``, ``__iter__``, ``__getslice__``, + ``__setslice__``, ``__reversed__`` and ``__missing__`` +* Context manager: ``__enter__`` and ``__exit__`` +* Unary numeric methods: ``__neg__``, ``__pos__`` and ``__invert__`` +* The numeric methods (including right hand and in-place variants): + ``__add__``, ``__sub__``, ``__mul__``, ``__div__``, + ``__floordiv__``, ``__mod__``, ``__divmod__``, ``__lshift__``, + ``__rshift__``, ``__and__``, ``__xor__``, ``__or__``, and ``__pow__`` +* Numeric conversion methods: ``__complex__``, ``__int__``, ``__float__``, + ``__index__`` and ``__coerce__`` +* Descriptor methods: ``__get__``, ``__set__`` and ``__delete__`` +* Pickling: ``__reduce__``, ``__reduce_ex__``, ``__getinitargs__``, + ``__getnewargs__``, ``__getstate__`` and ``__setstate__`` + + +The following methods are supported in Python 2 but don't exist in Python 3: + +* ``__unicode__``, ``__long__``, ``__oct__``, ``__hex__`` and ``__nonzero__`` +* ``__truediv__`` and ``__rtruediv__`` + +The following methods are supported in Python 3 but don't exist in Python 2: + +* ``__bool__`` and ``__next__`` + +The following methods exist but are *not* supported as they are either in use by +mock, can't be set dynamically, or can cause problems: + +* ``__getattr__``, ``__setattr__``, ``__init__`` and ``__new__`` +* ``__prepare__``, ``__instancecheck__``, ``__subclasscheck__``, ``__del__`` + + + +Magic Mock +========== + +There are two `MagicMock` variants: `MagicMock` and `NonCallableMagicMock`. + + +.. class:: MagicMock(*args, **kw) + + ``MagicMock`` is a subclass of :class:`Mock` with default implementations + of most of the magic methods. You can use ``MagicMock`` without having to + configure the magic methods yourself. + + The constructor parameters have the same meaning as for :class:`Mock`. + + If you use the `spec` or `spec_set` arguments then *only* magic methods + that exist in the spec will be created. + + +.. class:: NonCallableMagicMock(*args, **kw) + + A non-callable version of `MagicMock`. + + The constructor parameters have the same meaning as for + :class:`MagicMock`, with the exception of `return_value` and + `side_effect` which have no meaning on a non-callable mock. + +The magic methods are setup with `MagicMock` objects, so you can configure them +and use them in the usual way: + +.. doctest:: + + >>> mock = MagicMock() + >>> mock[3] = 'fish' + >>> mock.__setitem__.assert_called_with(3, 'fish') + >>> mock.__getitem__.return_value = 'result' + >>> mock[2] + 'result' + +By default many of the protocol methods are required to return objects of a +specific type. These methods are preconfigured with a default return value, so +that they can be used without you having to do anything if you aren't interested +in the return value. You can still *set* the return value manually if you want +to change the default. + +Methods and their defaults: + +* ``__lt__``: NotImplemented +* ``__gt__``: NotImplemented +* ``__le__``: NotImplemented +* ``__ge__``: NotImplemented +* ``__int__`` : 1 +* ``__contains__`` : False +* ``__len__`` : 1 +* ``__iter__`` : iter([]) +* ``__exit__`` : False +* ``__complex__`` : 1j +* ``__float__`` : 1.0 +* ``__bool__`` : True +* ``__nonzero__`` : True +* ``__oct__`` : '1' +* ``__hex__`` : '0x1' +* ``__long__`` : long(1) +* ``__index__`` : 1 +* ``__hash__`` : default hash for the mock +* ``__str__`` : default str for the mock +* ``__unicode__`` : default unicode for the mock +* ``__sizeof__``: default sizeof for the mock + +For example: + +.. doctest:: + + >>> mock = MagicMock() + >>> int(mock) + 1 + >>> len(mock) + 0 + >>> hex(mock) + '0x1' + >>> list(mock) + [] + >>> object() in mock + False + +The two equality method, `__eq__` and `__ne__`, are special (changed in +0.7.2). They do the default equality comparison on identity, using a side +effect, unless you change their return value to return something else: + +.. doctest:: + + >>> MagicMock() == 3 + False + >>> MagicMock() != 3 + True + >>> mock = MagicMock() + >>> mock.__eq__.return_value = True + >>> mock == 3 + True + +In `0.8` the `__iter__` also gained special handling implemented with a +side effect. The return value of `MagicMock.__iter__` can be any iterable +object and isn't required to be an iterator: + +.. doctest:: + + >>> mock = MagicMock() + >>> mock.__iter__.return_value = ['a', 'b', 'c'] + >>> list(mock) + ['a', 'b', 'c'] + >>> list(mock) + ['a', 'b', 'c'] + +If the return value *is* an iterator, then iterating over it once will consume +it and subsequent iterations will result in an empty list: + +.. doctest:: + + >>> mock.__iter__.return_value = iter(['a', 'b', 'c']) + >>> list(mock) + ['a', 'b', 'c'] + >>> list(mock) + [] + +``MagicMock`` has all of the supported magic methods configured except for some +of the obscure and obsolete ones. You can still set these up if you want. + +Magic methods that are supported but not setup by default in ``MagicMock`` are: + +* ``__cmp__`` +* ``__getslice__`` and ``__setslice__`` +* ``__coerce__`` +* ``__subclasses__`` +* ``__dir__`` +* ``__format__`` +* ``__get__``, ``__set__`` and ``__delete__`` +* ``__reversed__`` and ``__missing__`` +* ``__reduce__``, ``__reduce_ex__``, ``__getinitargs__``, ``__getnewargs__``, + ``__getstate__`` and ``__setstate__`` +* ``__getformat__`` and ``__setformat__`` + + + +------------ + +.. [#] Magic methods *should* be looked up on the class rather than the + instance. Different versions of Python are inconsistent about applying this + rule. The supported protocol methods should work with all supported versions + of Python. +.. [#] The function is basically hooked up to the class, but each ``Mock`` + instance is kept isolated from the others. |