From 40ee551715c3a784ea6132dbf604b0e665ca2def Mon Sep 17 00:00:00 2001 From: temporal Date: Thu, 10 Jul 2008 02:12:20 +0000 Subject: Initial checkin. --- python/mox.py | 1401 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1401 insertions(+) create mode 100755 python/mox.py (limited to 'python/mox.py') diff --git a/python/mox.py b/python/mox.py new file mode 100755 index 00000000..ce80ba50 --- /dev/null +++ b/python/mox.py @@ -0,0 +1,1401 @@ +#!/usr/bin/python2.4 +# +# Copyright 2008 Google Inc. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +# This file is used for testing. The original is at: +# http://code.google.com/p/pymox/ + +"""Mox, an object-mocking framework for Python. + +Mox works in the record-replay-verify paradigm. When you first create +a mock object, it is in record mode. You then programmatically set +the expected behavior of the mock object (what methods are to be +called on it, with what parameters, what they should return, and in +what order). + +Once you have set up the expected mock behavior, you put it in replay +mode. Now the mock responds to method calls just as you told it to. +If an unexpected method (or an expected method with unexpected +parameters) is called, then an exception will be raised. + +Once you are done interacting with the mock, you need to verify that +all the expected interactions occured. (Maybe your code exited +prematurely without calling some cleanup method!) The verify phase +ensures that every expected method was called; otherwise, an exception +will be raised. + +Suggested usage / workflow: + + # Create Mox factory + my_mox = Mox() + + # Create a mock data access object + mock_dao = my_mox.CreateMock(DAOClass) + + # Set up expected behavior + mock_dao.RetrievePersonWithIdentifier('1').AndReturn(person) + mock_dao.DeletePerson(person) + + # Put mocks in replay mode + my_mox.ReplayAll() + + # Inject mock object and run test + controller.SetDao(mock_dao) + controller.DeletePersonById('1') + + # Verify all methods were called as expected + my_mox.VerifyAll() +""" + +from collections import deque +import re +import types +import unittest + +import stubout + +class Error(AssertionError): + """Base exception for this module.""" + + pass + + +class ExpectedMethodCallsError(Error): + """Raised when Verify() is called before all expected methods have been called + """ + + def __init__(self, expected_methods): + """Init exception. + + Args: + # expected_methods: A sequence of MockMethod objects that should have been + # called. + expected_methods: [MockMethod] + + Raises: + ValueError: if expected_methods contains no methods. + """ + + if not expected_methods: + raise ValueError("There must be at least one expected method") + Error.__init__(self) + self._expected_methods = expected_methods + + def __str__(self): + calls = "\n".join(["%3d. %s" % (i, m) + for i, m in enumerate(self._expected_methods)]) + return "Verify: Expected methods never called:\n%s" % (calls,) + + +class UnexpectedMethodCallError(Error): + """Raised when an unexpected method is called. + + This can occur if a method is called with incorrect parameters, or out of the + specified order. + """ + + def __init__(self, unexpected_method, expected): + """Init exception. + + Args: + # unexpected_method: MockMethod that was called but was not at the head of + # the expected_method queue. + # expected: MockMethod or UnorderedGroup the method should have + # been in. + unexpected_method: MockMethod + expected: MockMethod or UnorderedGroup + """ + + Error.__init__(self) + self._unexpected_method = unexpected_method + self._expected = expected + + def __str__(self): + return "Unexpected method call: %s. Expecting: %s" % \ + (self._unexpected_method, self._expected) + + +class UnknownMethodCallError(Error): + """Raised if an unknown method is requested of the mock object.""" + + def __init__(self, unknown_method_name): + """Init exception. + + Args: + # unknown_method_name: Method call that is not part of the mocked class's + # public interface. + unknown_method_name: str + """ + + Error.__init__(self) + self._unknown_method_name = unknown_method_name + + def __str__(self): + return "Method called is not a member of the object: %s" % \ + self._unknown_method_name + + +class Mox(object): + """Mox: a factory for creating mock objects.""" + + # A list of types that should be stubbed out with MockObjects (as + # opposed to MockAnythings). + _USE_MOCK_OBJECT = [types.ClassType, types.InstanceType, types.ModuleType, + types.ObjectType, types.TypeType] + + def __init__(self): + """Initialize a new Mox.""" + + self._mock_objects = [] + self.stubs = stubout.StubOutForTesting() + + def CreateMock(self, class_to_mock): + """Create a new mock object. + + Args: + # class_to_mock: the class to be mocked + class_to_mock: class + + Returns: + MockObject that can be used as the class_to_mock would be. + """ + + new_mock = MockObject(class_to_mock) + self._mock_objects.append(new_mock) + return new_mock + + def CreateMockAnything(self): + """Create a mock that will accept any method calls. + + This does not enforce an interface. + """ + + new_mock = MockAnything() + self._mock_objects.append(new_mock) + return new_mock + + def ReplayAll(self): + """Set all mock objects to replay mode.""" + + for mock_obj in self._mock_objects: + mock_obj._Replay() + + + def VerifyAll(self): + """Call verify on all mock objects created.""" + + for mock_obj in self._mock_objects: + mock_obj._Verify() + + def ResetAll(self): + """Call reset on all mock objects. This does not unset stubs.""" + + for mock_obj in self._mock_objects: + mock_obj._Reset() + + def StubOutWithMock(self, obj, attr_name, use_mock_anything=False): + """Replace a method, attribute, etc. with a Mock. + + This will replace a class or module with a MockObject, and everything else + (method, function, etc) with a MockAnything. This can be overridden to + always use a MockAnything by setting use_mock_anything to True. + + Args: + obj: A Python object (class, module, instance, callable). + attr_name: str. The name of the attribute to replace with a mock. + use_mock_anything: bool. True if a MockAnything should be used regardless + of the type of attribute. + """ + + attr_to_replace = getattr(obj, attr_name) + if type(attr_to_replace) in self._USE_MOCK_OBJECT and not use_mock_anything: + stub = self.CreateMock(attr_to_replace) + else: + stub = self.CreateMockAnything() + + self.stubs.Set(obj, attr_name, stub) + + def UnsetStubs(self): + """Restore stubs to their original state.""" + + self.stubs.UnsetAll() + +def Replay(*args): + """Put mocks into Replay mode. + + Args: + # args is any number of mocks to put into replay mode. + """ + + for mock in args: + mock._Replay() + + +def Verify(*args): + """Verify mocks. + + Args: + # args is any number of mocks to be verified. + """ + + for mock in args: + mock._Verify() + + +def Reset(*args): + """Reset mocks. + + Args: + # args is any number of mocks to be reset. + """ + + for mock in args: + mock._Reset() + + +class MockAnything: + """A mock that can be used to mock anything. + + This is helpful for mocking classes that do not provide a public interface. + """ + + def __init__(self): + """ """ + self._Reset() + + def __getattr__(self, method_name): + """Intercept method calls on this object. + + A new MockMethod is returned that is aware of the MockAnything's + state (record or replay). The call will be recorded or replayed + by the MockMethod's __call__. + + Args: + # method name: the name of the method being called. + method_name: str + + Returns: + A new MockMethod aware of MockAnything's state (record or replay). + """ + + return self._CreateMockMethod(method_name) + + def _CreateMockMethod(self, method_name): + """Create a new mock method call and return it. + + Args: + # method name: the name of the method being called. + method_name: str + + Returns: + A new MockMethod aware of MockAnything's state (record or replay). + """ + + return MockMethod(method_name, self._expected_calls_queue, + self._replay_mode) + + def __nonzero__(self): + """Return 1 for nonzero so the mock can be used as a conditional.""" + + return 1 + + def __eq__(self, rhs): + """Provide custom logic to compare objects.""" + + return (isinstance(rhs, MockAnything) and + self._replay_mode == rhs._replay_mode and + self._expected_calls_queue == rhs._expected_calls_queue) + + def __ne__(self, rhs): + """Provide custom logic to compare objects.""" + + return not self == rhs + + def _Replay(self): + """Start replaying expected method calls.""" + + self._replay_mode = True + + def _Verify(self): + """Verify that all of the expected calls have been made. + + Raises: + ExpectedMethodCallsError: if there are still more method calls in the + expected queue. + """ + + # If the list of expected calls is not empty, raise an exception + if self._expected_calls_queue: + # The last MultipleTimesGroup is not popped from the queue. + if (len(self._expected_calls_queue) == 1 and + isinstance(self._expected_calls_queue[0], MultipleTimesGroup) and + self._expected_calls_queue[0].IsSatisfied()): + pass + else: + raise ExpectedMethodCallsError(self._expected_calls_queue) + + def _Reset(self): + """Reset the state of this mock to record mode with an empty queue.""" + + # Maintain a list of method calls we are expecting + self._expected_calls_queue = deque() + + # Make sure we are in setup mode, not replay mode + self._replay_mode = False + + +class MockObject(MockAnything, object): + """A mock object that simulates the public/protected interface of a class.""" + + def __init__(self, class_to_mock): + """Initialize a mock object. + + This determines the methods and properties of the class and stores them. + + Args: + # class_to_mock: class to be mocked + class_to_mock: class + """ + + # This is used to hack around the mixin/inheritance of MockAnything, which + # is not a proper object (it can be anything. :-) + MockAnything.__dict__['__init__'](self) + + # Get a list of all the public and special methods we should mock. + self._known_methods = set() + self._known_vars = set() + self._class_to_mock = class_to_mock + for method in dir(class_to_mock): + if callable(getattr(class_to_mock, method)): + self._known_methods.add(method) + else: + self._known_vars.add(method) + + def __getattr__(self, name): + """Intercept attribute request on this object. + + If the attribute is a public class variable, it will be returned and not + recorded as a call. + + If the attribute is not a variable, it is handled like a method + call. The method name is checked against the set of mockable + methods, and a new MockMethod is returned that is aware of the + MockObject's state (record or replay). The call will be recorded + or replayed by the MockMethod's __call__. + + Args: + # name: the name of the attribute being requested. + name: str + + Returns: + Either a class variable or a new MockMethod that is aware of the state + of the mock (record or replay). + + Raises: + UnknownMethodCallError if the MockObject does not mock the requested + method. + """ + + if name in self._known_vars: + return getattr(self._class_to_mock, name) + + if name in self._known_methods: + return self._CreateMockMethod(name) + + raise UnknownMethodCallError(name) + + def __eq__(self, rhs): + """Provide custom logic to compare objects.""" + + return (isinstance(rhs, MockObject) and + self._class_to_mock == rhs._class_to_mock and + self._replay_mode == rhs._replay_mode and + self._expected_calls_queue == rhs._expected_calls_queue) + + def __setitem__(self, key, value): + """Provide custom logic for mocking classes that support item assignment. + + Args: + key: Key to set the value for. + value: Value to set. + + Returns: + Expected return value in replay mode. A MockMethod object for the + __setitem__ method that has already been called if not in replay mode. + + Raises: + TypeError if the underlying class does not support item assignment. + UnexpectedMethodCallError if the object does not expect the call to + __setitem__. + + """ + setitem = self._class_to_mock.__dict__.get('__setitem__', None) + + # Verify the class supports item assignment. + if setitem is None: + raise TypeError('object does not support item assignment') + + # If we are in replay mode then simply call the mock __setitem__ method. + if self._replay_mode: + return MockMethod('__setitem__', self._expected_calls_queue, + self._replay_mode)(key, value) + + + # Otherwise, create a mock method __setitem__. + return self._CreateMockMethod('__setitem__')(key, value) + + def __getitem__(self, key): + """Provide custom logic for mocking classes that are subscriptable. + + Args: + key: Key to return the value for. + + Returns: + Expected return value in replay mode. A MockMethod object for the + __getitem__ method that has already been called if not in replay mode. + + Raises: + TypeError if the underlying class is not subscriptable. + UnexpectedMethodCallError if the object does not expect the call to + __setitem__. + + """ + getitem = self._class_to_mock.__dict__.get('__getitem__', None) + + # Verify the class supports item assignment. + if getitem is None: + raise TypeError('unsubscriptable object') + + # If we are in replay mode then simply call the mock __getitem__ method. + if self._replay_mode: + return MockMethod('__getitem__', self._expected_calls_queue, + self._replay_mode)(key) + + + # Otherwise, create a mock method __getitem__. + return self._CreateMockMethod('__getitem__')(key) + + def __call__(self, *params, **named_params): + """Provide custom logic for mocking classes that are callable.""" + + # Verify the class we are mocking is callable + callable = self._class_to_mock.__dict__.get('__call__', None) + if callable is None: + raise TypeError('Not callable') + + # Because the call is happening directly on this object instead of a method, + # the call on the mock method is made right here + mock_method = self._CreateMockMethod('__call__') + return mock_method(*params, **named_params) + + @property + def __class__(self): + """Return the class that is being mocked.""" + + return self._class_to_mock + + +class MockMethod(object): + """Callable mock method. + + A MockMethod should act exactly like the method it mocks, accepting parameters + and returning a value, or throwing an exception (as specified). When this + method is called, it can optionally verify whether the called method (name and + signature) matches the expected method. + """ + + def __init__(self, method_name, call_queue, replay_mode): + """Construct a new mock method. + + Args: + # method_name: the name of the method + # call_queue: deque of calls, verify this call against the head, or add + # this call to the queue. + # replay_mode: False if we are recording, True if we are verifying calls + # against the call queue. + method_name: str + call_queue: list or deque + replay_mode: bool + """ + + self._name = method_name + self._call_queue = call_queue + if not isinstance(call_queue, deque): + self._call_queue = deque(self._call_queue) + self._replay_mode = replay_mode + + self._params = None + self._named_params = None + self._return_value = None + self._exception = None + self._side_effects = None + + def __call__(self, *params, **named_params): + """Log parameters and return the specified return value. + + If the Mock(Anything/Object) associated with this call is in record mode, + this MockMethod will be pushed onto the expected call queue. If the mock + is in replay mode, this will pop a MockMethod off the top of the queue and + verify this call is equal to the expected call. + + Raises: + UnexpectedMethodCall if this call is supposed to match an expected method + call and it does not. + """ + + self._params = params + self._named_params = named_params + + if not self._replay_mode: + self._call_queue.append(self) + return self + + expected_method = self._VerifyMethodCall() + + if expected_method._side_effects: + expected_method._side_effects(*params, **named_params) + + if expected_method._exception: + raise expected_method._exception + + return expected_method._return_value + + def __getattr__(self, name): + """Raise an AttributeError with a helpful message.""" + + raise AttributeError('MockMethod has no attribute "%s". ' + 'Did you remember to put your mocks in replay mode?' % name) + + def _PopNextMethod(self): + """Pop the next method from our call queue.""" + try: + return self._call_queue.popleft() + except IndexError: + raise UnexpectedMethodCallError(self, None) + + def _VerifyMethodCall(self): + """Verify the called method is expected. + + This can be an ordered method, or part of an unordered set. + + Returns: + The expected mock method. + + Raises: + UnexpectedMethodCall if the method called was not expected. + """ + + expected = self._PopNextMethod() + + # Loop here, because we might have a MethodGroup followed by another + # group. + while isinstance(expected, MethodGroup): + expected, method = expected.MethodCalled(self) + if method is not None: + return method + + # This is a mock method, so just check equality. + if expected != self: + raise UnexpectedMethodCallError(self, expected) + + return expected + + def __str__(self): + params = ', '.join( + [repr(p) for p in self._params or []] + + ['%s=%r' % x for x in sorted((self._named_params or {}).items())]) + desc = "%s(%s) -> %r" % (self._name, params, self._return_value) + return desc + + def __eq__(self, rhs): + """Test whether this MockMethod is equivalent to another MockMethod. + + Args: + # rhs: the right hand side of the test + rhs: MockMethod + """ + + return (isinstance(rhs, MockMethod) and + self._name == rhs._name and + self._params == rhs._params and + self._named_params == rhs._named_params) + + def __ne__(self, rhs): + """Test whether this MockMethod is not equivalent to another MockMethod. + + Args: + # rhs: the right hand side of the test + rhs: MockMethod + """ + + return not self == rhs + + def GetPossibleGroup(self): + """Returns a possible group from the end of the call queue or None if no + other methods are on the stack. + """ + + # Remove this method from the tail of the queue so we can add it to a group. + this_method = self._call_queue.pop() + assert this_method == self + + # Determine if the tail of the queue is a group, or just a regular ordered + # mock method. + group = None + try: + group = self._call_queue[-1] + except IndexError: + pass + + return group + + def _CheckAndCreateNewGroup(self, group_name, group_class): + """Checks if the last method (a possible group) is an instance of our + group_class. Adds the current method to this group or creates a new one. + + Args: + + group_name: the name of the group. + group_class: the class used to create instance of this new group + """ + group = self.GetPossibleGroup() + + # If this is a group, and it is the correct group, add the method. + if isinstance(group, group_class) and group.group_name() == group_name: + group.AddMethod(self) + return self + + # Create a new group and add the method. + new_group = group_class(group_name) + new_group.AddMethod(self) + self._call_queue.append(new_group) + return self + + def InAnyOrder(self, group_name="default"): + """Move this method into a group of unordered calls. + + A group of unordered calls must be defined together, and must be executed + in full before the next expected method can be called. There can be + multiple groups that are expected serially, if they are given + different group names. The same group name can be reused if there is a + standard method call, or a group with a different name, spliced between + usages. + + Args: + group_name: the name of the unordered group. + + Returns: + self + """ + return self._CheckAndCreateNewGroup(group_name, UnorderedGroup) + + def MultipleTimes(self, group_name="default"): + """Move this method into group of calls which may be called multiple times. + + A group of repeating calls must be defined together, and must be executed in + full before the next expected mehtod can be called. + + Args: + group_name: the name of the unordered group. + + Returns: + self + """ + return self._CheckAndCreateNewGroup(group_name, MultipleTimesGroup) + + def AndReturn(self, return_value): + """Set the value to return when this method is called. + + Args: + # return_value can be anything. + """ + + self._return_value = return_value + return return_value + + def AndRaise(self, exception): + """Set the exception to raise when this method is called. + + Args: + # exception: the exception to raise when this method is called. + exception: Exception + """ + + self._exception = exception + + def WithSideEffects(self, side_effects): + """Set the side effects that are simulated when this method is called. + + Args: + side_effects: A callable which modifies the parameters or other relevant + state which a given test case depends on. + + Returns: + Self for chaining with AndReturn and AndRaise. + """ + self._side_effects = side_effects + return self + +class Comparator: + """Base class for all Mox comparators. + + A Comparator can be used as a parameter to a mocked method when the exact + value is not known. For example, the code you are testing might build up a + long SQL string that is passed to your mock DAO. You're only interested that + the IN clause contains the proper primary keys, so you can set your mock + up as follows: + + mock_dao.RunQuery(StrContains('IN (1, 2, 4, 5)')).AndReturn(mock_result) + + Now whatever query is passed in must contain the string 'IN (1, 2, 4, 5)'. + + A Comparator may replace one or more parameters, for example: + # return at most 10 rows + mock_dao.RunQuery(StrContains('SELECT'), 10) + + or + + # Return some non-deterministic number of rows + mock_dao.RunQuery(StrContains('SELECT'), IsA(int)) + """ + + def equals(self, rhs): + """Special equals method that all comparators must implement. + + Args: + rhs: any python object + """ + + raise NotImplementedError, 'method must be implemented by a subclass.' + + def __eq__(self, rhs): + return self.equals(rhs) + + def __ne__(self, rhs): + return not self.equals(rhs) + + +class IsA(Comparator): + """This class wraps a basic Python type or class. It is used to verify + that a parameter is of the given type or class. + + Example: + mock_dao.Connect(IsA(DbConnectInfo)) + """ + + def __init__(self, class_name): + """Initialize IsA + + Args: + class_name: basic python type or a class + """ + + self._class_name = class_name + + def equals(self, rhs): + """Check to see if the RHS is an instance of class_name. + + Args: + # rhs: the right hand side of the test + rhs: object + + Returns: + bool + """ + + try: + return isinstance(rhs, self._class_name) + except TypeError: + # Check raw types if there was a type error. This is helpful for + # things like cStringIO.StringIO. + return type(rhs) == type(self._class_name) + + def __repr__(self): + return str(self._class_name) + +class IsAlmost(Comparator): + """Comparison class used to check whether a parameter is nearly equal + to a given value. Generally useful for floating point numbers. + + Example mock_dao.SetTimeout((IsAlmost(3.9))) + """ + + def __init__(self, float_value, places=7): + """Initialize IsAlmost. + + Args: + float_value: The value for making the comparison. + places: The number of decimal places to round to. + """ + + self._float_value = float_value + self._places = places + + def equals(self, rhs): + """Check to see if RHS is almost equal to float_value + + Args: + rhs: the value to compare to float_value + + Returns: + bool + """ + + try: + return round(rhs-self._float_value, self._places) == 0 + except TypeError: + # This is probably because either float_value or rhs is not a number. + return False + + def __repr__(self): + return str(self._float_value) + +class StrContains(Comparator): + """Comparison class used to check whether a substring exists in a + string parameter. This can be useful in mocking a database with SQL + passed in as a string parameter, for example. + + Example: + mock_dao.RunQuery(StrContains('IN (1, 2, 4, 5)')).AndReturn(mock_result) + """ + + def __init__(self, search_string): + """Initialize. + + Args: + # search_string: the string you are searching for + search_string: str + """ + + self._search_string = search_string + + def equals(self, rhs): + """Check to see if the search_string is contained in the rhs string. + + Args: + # rhs: the right hand side of the test + rhs: object + + Returns: + bool + """ + + try: + return rhs.find(self._search_string) > -1 + except Exception: + return False + + def __repr__(self): + return '' % self._search_string + + +class Regex(Comparator): + """Checks if a string matches a regular expression. + + This uses a given regular expression to determine equality. + """ + + def __init__(self, pattern, flags=0): + """Initialize. + + Args: + # pattern is the regular expression to search for + pattern: str + # flags passed to re.compile function as the second argument + flags: int + """ + + self.regex = re.compile(pattern, flags=flags) + + def equals(self, rhs): + """Check to see if rhs matches regular expression pattern. + + Returns: + bool + """ + + return self.regex.search(rhs) is not None + + def __repr__(self): + s = '' % self._key + + +class ContainsKeyValue(Comparator): + """Checks whether a key/value pair is in a dict parameter. + + Example: + mock_dao.UpdateUsers(ContainsKeyValue('stevepm', stevepm_user_info)) + """ + + def __init__(self, key, value): + """Initialize. + + Args: + # key: a key in a dict + # value: the corresponding value + """ + + self._key = key + self._value = value + + def equals(self, rhs): + """Check whether the given key/value pair is in the rhs dict. + + Returns: + bool + """ + + try: + return rhs[self._key] == self._value + except Exception: + return False + + def __repr__(self): + return '' % (self._key, self._value) + + +class SameElementsAs(Comparator): + """Checks whether iterables contain the same elements (ignoring order). + + Example: + mock_dao.ProcessUsers(SameElementsAs('stevepm', 'salomaki')) + """ + + def __init__(self, expected_seq): + """Initialize. + + Args: + expected_seq: a sequence + """ + + self._expected_seq = expected_seq + + def equals(self, actual_seq): + """Check to see whether actual_seq has same elements as expected_seq. + + Args: + actual_seq: sequence + + Returns: + bool + """ + + try: + expected = dict([(element, None) for element in self._expected_seq]) + actual = dict([(element, None) for element in actual_seq]) + except TypeError: + # Fall back to slower list-compare if any of the objects are unhashable. + expected = list(self._expected_seq) + actual = list(actual_seq) + expected.sort() + actual.sort() + return expected == actual + + def __repr__(self): + return '' % self._expected_seq + + +class And(Comparator): + """Evaluates one or more Comparators on RHS and returns an AND of the results. + """ + + def __init__(self, *args): + """Initialize. + + Args: + *args: One or more Comparator + """ + + self._comparators = args + + def equals(self, rhs): + """Checks whether all Comparators are equal to rhs. + + Args: + # rhs: can be anything + + Returns: + bool + """ + + for comparator in self._comparators: + if not comparator.equals(rhs): + return False + + return True + + def __repr__(self): + return '' % str(self._comparators) + + +class Or(Comparator): + """Evaluates one or more Comparators on RHS and returns an OR of the results. + """ + + def __init__(self, *args): + """Initialize. + + Args: + *args: One or more Mox comparators + """ + + self._comparators = args + + def equals(self, rhs): + """Checks whether any Comparator is equal to rhs. + + Args: + # rhs: can be anything + + Returns: + bool + """ + + for comparator in self._comparators: + if comparator.equals(rhs): + return True + + return False + + def __repr__(self): + return '' % str(self._comparators) + + +class Func(Comparator): + """Call a function that should verify the parameter passed in is correct. + + You may need the ability to perform more advanced operations on the parameter + in order to validate it. You can use this to have a callable validate any + parameter. The callable should return either True or False. + + + Example: + + def myParamValidator(param): + # Advanced logic here + return True + + mock_dao.DoSomething(Func(myParamValidator), true) + """ + + def __init__(self, func): + """Initialize. + + Args: + func: callable that takes one parameter and returns a bool + """ + + self._func = func + + def equals(self, rhs): + """Test whether rhs passes the function test. + + rhs is passed into func. + + Args: + rhs: any python object + + Returns: + the result of func(rhs) + """ + + return self._func(rhs) + + def __repr__(self): + return str(self._func) + + +class IgnoreArg(Comparator): + """Ignore an argument. + + This can be used when we don't care about an argument of a method call. + + Example: + # Check if CastMagic is called with 3 as first arg and 'disappear' as third. + mymock.CastMagic(3, IgnoreArg(), 'disappear') + """ + + def equals(self, unused_rhs): + """Ignores arguments and returns True. + + Args: + unused_rhs: any python object + + Returns: + always returns True + """ + + return True + + def __repr__(self): + return '' + + +class MethodGroup(object): + """Base class containing common behaviour for MethodGroups.""" + + def __init__(self, group_name): + self._group_name = group_name + + def group_name(self): + return self._group_name + + def __str__(self): + return '<%s "%s">' % (self.__class__.__name__, self._group_name) + + def AddMethod(self, mock_method): + raise NotImplementedError + + def MethodCalled(self, mock_method): + raise NotImplementedError + + def IsSatisfied(self): + raise NotImplementedError + +class UnorderedGroup(MethodGroup): + """UnorderedGroup holds a set of method calls that may occur in any order. + + This construct is helpful for non-deterministic events, such as iterating + over the keys of a dict. + """ + + def __init__(self, group_name): + super(UnorderedGroup, self).__init__(group_name) + self._methods = [] + + def AddMethod(self, mock_method): + """Add a method to this group. + + Args: + mock_method: A mock method to be added to this group. + """ + + self._methods.append(mock_method) + + def MethodCalled(self, mock_method): + """Remove a method call from the group. + + If the method is not in the set, an UnexpectedMethodCallError will be + raised. + + Args: + mock_method: a mock method that should be equal to a method in the group. + + Returns: + The mock method from the group + + Raises: + UnexpectedMethodCallError if the mock_method was not in the group. + """ + + # Check to see if this method exists, and if so, remove it from the set + # and return it. + for method in self._methods: + if method == mock_method: + # Remove the called mock_method instead of the method in the group. + # The called method will match any comparators when equality is checked + # during removal. The method in the group could pass a comparator to + # another comparator during the equality check. + self._methods.remove(mock_method) + + # If this group is not empty, put it back at the head of the queue. + if not self.IsSatisfied(): + mock_method._call_queue.appendleft(self) + + return self, method + + raise UnexpectedMethodCallError(mock_method, self) + + def IsSatisfied(self): + """Return True if there are not any methods in this group.""" + + return len(self._methods) == 0 + + +class MultipleTimesGroup(MethodGroup): + """MultipleTimesGroup holds methods that may be called any number of times. + + Note: Each method must be called at least once. + + This is helpful, if you don't know or care how many times a method is called. + """ + + def __init__(self, group_name): + super(MultipleTimesGroup, self).__init__(group_name) + self._methods = set() + self._methods_called = set() + + def AddMethod(self, mock_method): + """Add a method to this group. + + Args: + mock_method: A mock method to be added to this group. + """ + + self._methods.add(mock_method) + + def MethodCalled(self, mock_method): + """Remove a method call from the group. + + If the method is not in the set, an UnexpectedMethodCallError will be + raised. + + Args: + mock_method: a mock method that should be equal to a method in the group. + + Returns: + The mock method from the group + + Raises: + UnexpectedMethodCallError if the mock_method was not in the group. + """ + + # Check to see if this method exists, and if so add it to the set of + # called methods. + + for method in self._methods: + if method == mock_method: + self._methods_called.add(mock_method) + # Always put this group back on top of the queue, because we don't know + # when we are done. + mock_method._call_queue.appendleft(self) + return self, method + + if self.IsSatisfied(): + next_method = mock_method._PopNextMethod(); + return next_method, None + else: + raise UnexpectedMethodCallError(mock_method, self) + + def IsSatisfied(self): + """Return True if all methods in this group are called at least once.""" + # NOTE(psycho): We can't use the simple set difference here because we want + # to match different parameters which are considered the same e.g. IsA(str) + # and some string. This solution is O(n^2) but n should be small. + tmp = self._methods.copy() + for called in self._methods_called: + for expected in tmp: + if called == expected: + tmp.remove(expected) + if not tmp: + return True + break + return False + + +class MoxMetaTestBase(type): + """Metaclass to add mox cleanup and verification to every test. + + As the mox unit testing class is being constructed (MoxTestBase or a + subclass), this metaclass will modify all test functions to call the + CleanUpMox method of the test class after they finish. This means that + unstubbing and verifying will happen for every test with no additional code, + and any failures will result in test failures as opposed to errors. + """ + + def __init__(cls, name, bases, d): + type.__init__(cls, name, bases, d) + + # also get all the attributes from the base classes to account + # for a case when test class is not the immediate child of MoxTestBase + for base in bases: + for attr_name in dir(base): + d[attr_name] = getattr(base, attr_name) + + for func_name, func in d.items(): + if func_name.startswith('test') and callable(func): + setattr(cls, func_name, MoxMetaTestBase.CleanUpTest(cls, func)) + + @staticmethod + def CleanUpTest(cls, func): + """Adds Mox cleanup code to any MoxTestBase method. + + Always unsets stubs after a test. Will verify all mocks for tests that + otherwise pass. + + Args: + cls: MoxTestBase or subclass; the class whose test method we are altering. + func: method; the method of the MoxTestBase test class we wish to alter. + + Returns: + The modified method. + """ + def new_method(self, *args, **kwargs): + mox_obj = getattr(self, 'mox', None) + cleanup_mox = False + if mox_obj and isinstance(mox_obj, Mox): + cleanup_mox = True + try: + func(self, *args, **kwargs) + finally: + if cleanup_mox: + mox_obj.UnsetStubs() + if cleanup_mox: + mox_obj.VerifyAll() + new_method.__name__ = func.__name__ + new_method.__doc__ = func.__doc__ + new_method.__module__ = func.__module__ + return new_method + + +class MoxTestBase(unittest.TestCase): + """Convenience test class to make stubbing easier. + + Sets up a "mox" attribute which is an instance of Mox - any mox tests will + want this. Also automatically unsets any stubs and verifies that all mock + methods have been called at the end of each test, eliminating boilerplate + code. + """ + + __metaclass__ = MoxMetaTestBase + + def setUp(self): + self.mox = Mox() -- cgit v1.2.3