def mock_constructor(target, class_name):
if not _is_string(class_name):
raise ValueError(
"Second argument must be a string with the name of the class.")
if _is_string(target):
target = testslide._importer(target)
mocked_class_id = (id(target), class_name)
if mocked_class_id in _mocked_classes:
original_class, mocked_class = _mocked_classes[mocked_class_id]
if not getattr(target, class_name) is mocked_class:
raise AssertionError(
"The class {} at {} was changed after mock_constructor() mocked "
"it!".format(class_name, target))
callable_mock = getattr(mocked_class, "__new__")
else:
original_class = getattr(target, class_name)
if not inspect.isclass(original_class):
raise ValueError("Target must be a class.")
def unpatcher():
setattr(target, class_name, original_class)
del _mocked_classes[mocked_class_id]
_unpatchers.append(unpatcher)
callable_mock = _CallableMock(original_class, "__new__")
mocked_class = type(
str(original_class.__name__ + "Mock"),
(original_class, ),
{"__new__": callable_mock},
)
setattr(target, class_name, mocked_class)
_mocked_classes[mocked_class_id] = (original_class, mocked_class)
def original_callable(_, *args, **kwargs):
return original_class(*args, **kwargs)
return _MockCallableDSL(
mocked_class,
"__new__",
callable_mock=callable_mock,
original_callable=original_callable,
prepend_first_arg=ANY,
)
def mock_constructor(target, class_name, allow_private=False):
if not isinstance(class_name, str):
raise ValueError(
"Second argument must be a string with the name of the class.")
_bail_if_private(class_name, allow_private)
if isinstance(target, str):
target = testslide._importer(target)
target_class_id = (id(target), class_name)
if target_class_id in _mocked_target_classes:
original_class, mocked_class = _mocked_target_classes[target_class_id]
if not getattr(target, class_name) is mocked_class:
raise AssertionError(
"The class {} at {} was changed after mock_constructor() mocked "
"it!".format(class_name, target))
callable_mock = mocked_class.__new__
else:
original_class = getattr(target, class_name)
if "__new__" in original_class.__dict__:
raise NotImplementedError(
"Usage with classes that define __new__() is currently not supported."
)
gc.collect()
instances = [
obj for obj in gc.get_referrers(original_class)
if type(obj) is original_class
]
if instances:
raise RuntimeError(
"mock_constructor() can not be used after instances of {} were created: {}"
.format(class_name, instances))
if not inspect.isclass(original_class):
raise ValueError("Target must be a class.")
elif not issubclass(original_class, object):
raise ValueError("Old style classes are not supported.")
callable_mock = _CallableMock(original_class, "__new__")
mocked_class = _patch_and_return_mocked_class(target, class_name,
target_class_id,
original_class,
callable_mock)
def original_callable(cls, *args, **kwargs):
global _init_args_from_original_callable, _init_kwargs_from_original_callable
assert cls is mocked_class
# Python unconditionally calls __init__ with the same arguments as
# __new__ once it is invoked. We save the correct arguments here,
# so that __init__ can use them when invoked for the first time.
_init_args_from_original_callable = args
_init_kwargs_from_original_callable = kwargs
return object.__new__(cls)
return _MockConstructorDSL(
target=mocked_class,
method="__new__",
cls=mocked_class,
callable_mock=callable_mock,
original_callable=original_callable,
)
def mock_constructor(
target: str,
class_name: str,
allow_private: bool = False,
type_validation: bool = True,
) -> _MockConstructorDSL:
if not isinstance(class_name, str):
raise ValueError("Second argument must be a string with the name of the class.")
_bail_if_private(class_name, allow_private)
if isinstance(target, str):
target = testslide._importer(target)
target_class_id = (id(target), class_name)
if target_class_id in _mocked_target_classes:
original_class, mocked_class = _mocked_target_classes[target_class_id]
if not getattr(target, class_name) is mocked_class:
raise AssertionError(
"The class {} at {} was changed after mock_constructor() mocked "
"it!".format(class_name, target)
)
callable_mock = mocked_class.__new__
else:
original_class = getattr(target, class_name)
if "__new__" in original_class.__dict__:
raise NotImplementedError(
"Usage with classes that define __new__() is currently not supported."
)
gc.collect()
instances = [
obj
for obj in gc.get_referrers(original_class)
if type(obj) is original_class
]
if instances:
raise RuntimeError(
"mock_constructor() can not be used after instances of {} were created: {}".format(
class_name, instances
)
)
if not inspect.isclass(original_class):
raise ValueError("Target must be a class.")
elif not issubclass(original_class, object):
raise ValueError("Old style classes are not supported.")
caller_frame = inspect.currentframe().f_back # type: ignore
# loading the context ends up reading files from disk and that might block
# the event loop, so we don't do it.
caller_frame_info = inspect.getframeinfo(caller_frame, context=0) # type: ignore
callable_mock = _CallableMock(original_class, "__new__", caller_frame_info)
mocked_class = _patch_and_return_mocked_class(
target,
class_name,
target_class_id,
original_class,
callable_mock,
type_validation,
)
def original_callable(cls: type, *args: Any, **kwargs: Any) -> Any:
global _init_args_from_original_callable, _init_kwargs_from_original_callable
assert cls is mocked_class
# Python unconditionally calls __init__ with the same arguments as
# __new__ once it is invoked. We save the correct arguments here,
# so that __init__ can use them when invoked for the first time.
_init_args_from_original_callable = args
_init_kwargs_from_original_callable = kwargs
return object.__new__(cls)
return _MockConstructorDSL(
target=mocked_class,
method="__new__",
cls=mocked_class,
callable_mock=callable_mock,
original_callable=original_callable,
)