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+
+
+# Defining a Mock Class #
+
+## Mocking a Normal Class ##
+
+Given
+```
+class Foo {
+ ...
+ virtual ~Foo();
+ virtual int GetSize() const = 0;
+ virtual string Describe(const char* name) = 0;
+ virtual string Describe(int type) = 0;
+ virtual bool Process(Bar elem, int count) = 0;
+};
+```
+(note that `~Foo()` **must** be virtual) we can define its mock as
+```
+#include "gmock/gmock.h"
+
+class MockFoo : public Foo {
+ MOCK_CONST_METHOD0(GetSize, int());
+ MOCK_METHOD1(Describe, string(const char* name));
+ MOCK_METHOD1(Describe, string(int type));
+ MOCK_METHOD2(Process, bool(Bar elem, int count));
+};
+```
+
+To create a "nice" mock object which ignores all uninteresting calls,
+or a "strict" mock object, which treats them as failures:
+```
+NiceMock<MockFoo> nice_foo; // The type is a subclass of MockFoo.
+StrictMock<MockFoo> strict_foo; // The type is a subclass of MockFoo.
+```
+
+## Mocking a Class Template ##
+
+To mock
+```
+template <typename Elem>
+class StackInterface {
+ public:
+ ...
+ virtual ~StackInterface();
+ virtual int GetSize() const = 0;
+ virtual void Push(const Elem& x) = 0;
+};
+```
+(note that `~StackInterface()` **must** be virtual) just append `_T` to the `MOCK_*` macros:
+```
+template <typename Elem>
+class MockStack : public StackInterface<Elem> {
+ public:
+ ...
+ MOCK_CONST_METHOD0_T(GetSize, int());
+ MOCK_METHOD1_T(Push, void(const Elem& x));
+};
+```
+
+## Specifying Calling Conventions for Mock Functions ##
+
+If your mock function doesn't use the default calling convention, you
+can specify it by appending `_WITH_CALLTYPE` to any of the macros
+described in the previous two sections and supplying the calling
+convention as the first argument to the macro. For example,
+```
+ MOCK_METHOD_1_WITH_CALLTYPE(STDMETHODCALLTYPE, Foo, bool(int n));
+ MOCK_CONST_METHOD2_WITH_CALLTYPE(STDMETHODCALLTYPE, Bar, int(double x, double y));
+```
+where `STDMETHODCALLTYPE` is defined by `<objbase.h>` on Windows.
+
+# Using Mocks in Tests #
+
+The typical flow is:
+ 1. Import the Google Mock names you need to use. All Google Mock names are in the `testing` namespace unless they are macros or otherwise noted.
+ 1. Create the mock objects.
+ 1. Optionally, set the default actions of the mock objects.
+ 1. Set your expectations on the mock objects (How will they be called? What wil they do?).
+ 1. Exercise code that uses the mock objects; if necessary, check the result using [Google Test](../../googletest/) assertions.
+ 1. When a mock objects is destructed, Google Mock automatically verifies that all expectations on it have been satisfied.
+
+Here is an example:
+```
+using ::testing::Return; // #1
+
+TEST(BarTest, DoesThis) {
+ MockFoo foo; // #2
+
+ ON_CALL(foo, GetSize()) // #3
+ .WillByDefault(Return(1));
+ // ... other default actions ...
+
+ EXPECT_CALL(foo, Describe(5)) // #4
+ .Times(3)
+ .WillRepeatedly(Return("Category 5"));
+ // ... other expectations ...
+
+ EXPECT_EQ("good", MyProductionFunction(&foo)); // #5
+} // #6
+```
+
+# Setting Default Actions #
+
+Google Mock has a **built-in default action** for any function that
+returns `void`, `bool`, a numeric value, or a pointer.
+
+To customize the default action for functions with return type `T` globally:
+```
+using ::testing::DefaultValue;
+
+// Sets the default value to be returned. T must be CopyConstructible.
+DefaultValue<T>::Set(value);
+// Sets a factory. Will be invoked on demand. T must be MoveConstructible.
+// T MakeT();
+DefaultValue<T>::SetFactory(&MakeT);
+// ... use the mocks ...
+// Resets the default value.
+DefaultValue<T>::Clear();
+```
+
+To customize the default action for a particular method, use `ON_CALL()`:
+```
+ON_CALL(mock_object, method(matchers))
+ .With(multi_argument_matcher) ?
+ .WillByDefault(action);
+```
+
+# Setting Expectations #
+
+`EXPECT_CALL()` sets **expectations** on a mock method (How will it be
+called? What will it do?):
+```
+EXPECT_CALL(mock_object, method(matchers))
+ .With(multi_argument_matcher) ?
+ .Times(cardinality) ?
+ .InSequence(sequences) *
+ .After(expectations) *
+ .WillOnce(action) *
+ .WillRepeatedly(action) ?
+ .RetiresOnSaturation(); ?
+```
+
+If `Times()` is omitted, the cardinality is assumed to be:
+
+ * `Times(1)` when there is neither `WillOnce()` nor `WillRepeatedly()`;
+ * `Times(n)` when there are `n WillOnce()`s but no `WillRepeatedly()`, where `n` >= 1; or
+ * `Times(AtLeast(n))` when there are `n WillOnce()`s and a `WillRepeatedly()`, where `n` >= 0.
+
+A method with no `EXPECT_CALL()` is free to be invoked _any number of times_, and the default action will be taken each time.
+
+# Matchers #
+
+A **matcher** matches a _single_ argument. You can use it inside
+`ON_CALL()` or `EXPECT_CALL()`, or use it to validate a value
+directly:
+
+| `EXPECT_THAT(value, matcher)` | Asserts that `value` matches `matcher`. |
+|:------------------------------|:----------------------------------------|
+| `ASSERT_THAT(value, matcher)` | The same as `EXPECT_THAT(value, matcher)`, except that it generates a **fatal** failure. |
+
+Built-in matchers (where `argument` is the function argument) are
+divided into several categories:
+
+## Wildcard ##
+|`_`|`argument` can be any value of the correct type.|
+|:--|:-----------------------------------------------|
+|`A<type>()` or `An<type>()`|`argument` can be any value of type `type`. |
+
+## Generic Comparison ##
+
+|`Eq(value)` or `value`|`argument == value`|
+|:---------------------|:------------------|
+|`Ge(value)` |`argument >= value`|
+|`Gt(value)` |`argument > value` |
+|`Le(value)` |`argument <= value`|
+|`Lt(value)` |`argument < value` |
+|`Ne(value)` |`argument != value`|
+|`IsNull()` |`argument` is a `NULL` pointer (raw or smart).|
+|`NotNull()` |`argument` is a non-null pointer (raw or smart).|
+|`Ref(variable)` |`argument` is a reference to `variable`.|
+|`TypedEq<type>(value)`|`argument` has type `type` and is equal to `value`. You may need to use this instead of `Eq(value)` when the mock function is overloaded.|
+
+Except `Ref()`, these matchers make a _copy_ of `value` in case it's
+modified or destructed later. If the compiler complains that `value`
+doesn't have a public copy constructor, try wrap it in `ByRef()`,
+e.g. `Eq(ByRef(non_copyable_value))`. If you do that, make sure
+`non_copyable_value` is not changed afterwards, or the meaning of your
+matcher will be changed.
+
+## Floating-Point Matchers ##
+
+|`DoubleEq(a_double)`|`argument` is a `double` value approximately equal to `a_double`, treating two NaNs as unequal.|
+|:-------------------|:----------------------------------------------------------------------------------------------|
+|`FloatEq(a_float)` |`argument` is a `float` value approximately equal to `a_float`, treating two NaNs as unequal. |
+|`NanSensitiveDoubleEq(a_double)`|`argument` is a `double` value approximately equal to `a_double`, treating two NaNs as equal. |
+|`NanSensitiveFloatEq(a_float)`|`argument` is a `float` value approximately equal to `a_float`, treating two NaNs as equal. |
+
+The above matchers use ULP-based comparison (the same as used in
+[Google Test](../../googletest/)). They
+automatically pick a reasonable error bound based on the absolute
+value of the expected value. `DoubleEq()` and `FloatEq()` conform to
+the IEEE standard, which requires comparing two NaNs for equality to
+return false. The `NanSensitive*` version instead treats two NaNs as
+equal, which is often what a user wants.
+
+|`DoubleNear(a_double, max_abs_error)`|`argument` is a `double` value close to `a_double` (absolute error <= `max_abs_error`), treating two NaNs as unequal.|
+|:------------------------------------|:--------------------------------------------------------------------------------------------------------------------|
+|`FloatNear(a_float, max_abs_error)` |`argument` is a `float` value close to `a_float` (absolute error <= `max_abs_error`), treating two NaNs as unequal. |
+|`NanSensitiveDoubleNear(a_double, max_abs_error)`|`argument` is a `double` value close to `a_double` (absolute error <= `max_abs_error`), treating two NaNs as equal. |
+|`NanSensitiveFloatNear(a_float, max_abs_error)`|`argument` is a `float` value close to `a_float` (absolute error <= `max_abs_error`), treating two NaNs as equal. |
+
+## String Matchers ##
+
+The `argument` can be either a C string or a C++ string object:
+
+|`ContainsRegex(string)`|`argument` matches the given regular expression.|
+|:----------------------|:-----------------------------------------------|
+|`EndsWith(suffix)` |`argument` ends with string `suffix`. |
+|`HasSubstr(string)` |`argument` contains `string` as a sub-string. |
+|`MatchesRegex(string)` |`argument` matches the given regular expression with the match starting at the first character and ending at the last character.|
+|`StartsWith(prefix)` |`argument` starts with string `prefix`. |
+|`StrCaseEq(string)` |`argument` is equal to `string`, ignoring case. |
+|`StrCaseNe(string)` |`argument` is not equal to `string`, ignoring case.|
+|`StrEq(string)` |`argument` is equal to `string`. |
+|`StrNe(string)` |`argument` is not equal to `string`. |
+
+`ContainsRegex()` and `MatchesRegex()` use the regular expression
+syntax defined
+[here](../../googletest/docs/AdvancedGuide.md#regular-expression-syntax).
+`StrCaseEq()`, `StrCaseNe()`, `StrEq()`, and `StrNe()` work for wide
+strings as well.
+
+## Container Matchers ##
+
+Most STL-style containers support `==`, so you can use
+`Eq(expected_container)` or simply `expected_container` to match a
+container exactly. If you want to write the elements in-line,
+match them more flexibly, or get more informative messages, you can use:
+
+| `ContainerEq(container)` | The same as `Eq(container)` except that the failure message also includes which elements are in one container but not the other. |
+|:-------------------------|:---------------------------------------------------------------------------------------------------------------------------------|
+| `Contains(e)` | `argument` contains an element that matches `e`, which can be either a value or a matcher. |
+| `Each(e)` | `argument` is a container where _every_ element matches `e`, which can be either a value or a matcher. |
+| `ElementsAre(e0, e1, ..., en)` | `argument` has `n + 1` elements, where the i-th element matches `ei`, which can be a value or a matcher. 0 to 10 arguments are allowed. |
+| `ElementsAreArray({ e0, e1, ..., en })`, `ElementsAreArray(array)`, or `ElementsAreArray(array, count)` | The same as `ElementsAre()` except that the expected element values/matchers come from an initializer list, STL-style container, or C-style array. |
+| `IsEmpty()` | `argument` is an empty container (`container.empty()`). |
+| `Pointwise(m, container)` | `argument` contains the same number of elements as in `container`, and for all i, (the i-th element in `argument`, the i-th element in `container`) match `m`, which is a matcher on 2-tuples. E.g. `Pointwise(Le(), upper_bounds)` verifies that each element in `argument` doesn't exceed the corresponding element in `upper_bounds`. See more detail below. |
+| `SizeIs(m)` | `argument` is a container whose size matches `m`. E.g. `SizeIs(2)` or `SizeIs(Lt(2))`. |
+| `UnorderedElementsAre(e0, e1, ..., en)` | `argument` has `n + 1` elements, and under some permutation each element matches an `ei` (for a different `i`), which can be a value or a matcher. 0 to 10 arguments are allowed. |
+| `UnorderedElementsAreArray({ e0, e1, ..., en })`, `UnorderedElementsAreArray(array)`, or `UnorderedElementsAreArray(array, count)` | The same as `UnorderedElementsAre()` except that the expected element values/matchers come from an initializer list, STL-style container, or C-style array. |
+| `WhenSorted(m)` | When `argument` is sorted using the `<` operator, it matches container matcher `m`. E.g. `WhenSorted(UnorderedElementsAre(1, 2, 3))` verifies that `argument` contains elements `1`, `2`, and `3`, ignoring order. |
+| `WhenSortedBy(comparator, m)` | The same as `WhenSorted(m)`, except that the given comparator instead of `<` is used to sort `argument`. E.g. `WhenSortedBy(std::greater<int>(), ElementsAre(3, 2, 1))`. |
+
+Notes:
+
+ * These matchers can also match:
+ 1. a native array passed by reference (e.g. in `Foo(const int (&a)[5])`), and
+ 1. an array passed as a pointer and a count (e.g. in `Bar(const T* buffer, int len)` -- see [Multi-argument Matchers](#Multiargument_Matchers.md)).
+ * The array being matched may be multi-dimensional (i.e. its elements can be arrays).
+ * `m` in `Pointwise(m, ...)` should be a matcher for `::testing::tuple<T, U>` where `T` and `U` are the element type of the actual container and the expected container, respectively. For example, to compare two `Foo` containers where `Foo` doesn't support `operator==` but has an `Equals()` method, one might write:
+
+```
+using ::testing::get;
+MATCHER(FooEq, "") {
+ return get<0>(arg).Equals(get<1>(arg));
+}
+...
+EXPECT_THAT(actual_foos, Pointwise(FooEq(), expected_foos));
+```
+
+## Member Matchers ##
+
+|`Field(&class::field, m)`|`argument.field` (or `argument->field` when `argument` is a plain pointer) matches matcher `m`, where `argument` is an object of type _class_.|
+|:------------------------|:---------------------------------------------------------------------------------------------------------------------------------------------|
+|`Key(e)` |`argument.first` matches `e`, which can be either a value or a matcher. E.g. `Contains(Key(Le(5)))` can verify that a `map` contains a key `<= 5`.|
+|`Pair(m1, m2)` |`argument` is an `std::pair` whose `first` field matches `m1` and `second` field matches `m2`. |
+|`Property(&class::property, m)`|`argument.property()` (or `argument->property()` when `argument` is a plain pointer) matches matcher `m`, where `argument` is an object of type _class_.|
+
+## Matching the Result of a Function or Functor ##
+
+|`ResultOf(f, m)`|`f(argument)` matches matcher `m`, where `f` is a function or functor.|
+|:---------------|:---------------------------------------------------------------------|
+
+## Pointer Matchers ##
+
+|`Pointee(m)`|`argument` (either a smart pointer or a raw pointer) points to a value that matches matcher `m`.|
+|:-----------|:-----------------------------------------------------------------------------------------------|
+|`WhenDynamicCastTo<T>(m)`| when `argument` is passed through `dynamic_cast<T>()`, it matches matcher `m`. |
+
+## Multiargument Matchers ##
+
+Technically, all matchers match a _single_ value. A "multi-argument"
+matcher is just one that matches a _tuple_. The following matchers can
+be used to match a tuple `(x, y)`:
+
+|`Eq()`|`x == y`|
+|:-----|:-------|
+|`Ge()`|`x >= y`|
+|`Gt()`|`x > y` |
+|`Le()`|`x <= y`|
+|`Lt()`|`x < y` |
+|`Ne()`|`x != y`|
+
+You can use the following selectors to pick a subset of the arguments
+(or reorder them) to participate in the matching:
+
+|`AllArgs(m)`|Equivalent to `m`. Useful as syntactic sugar in `.With(AllArgs(m))`.|
+|:-----------|:-------------------------------------------------------------------|
+|`Args<N1, N2, ..., Nk>(m)`|The tuple of the `k` selected (using 0-based indices) arguments matches `m`, e.g. `Args<1, 2>(Eq())`.|
+
+## Composite Matchers ##
+
+You can make a matcher from one or more other matchers:
+
+|`AllOf(m1, m2, ..., mn)`|`argument` matches all of the matchers `m1` to `mn`.|
+|:-----------------------|:---------------------------------------------------|
+|`AnyOf(m1, m2, ..., mn)`|`argument` matches at least one of the matchers `m1` to `mn`.|
+|`Not(m)` |`argument` doesn't match matcher `m`. |
+
+## Adapters for Matchers ##
+
+|`MatcherCast<T>(m)`|casts matcher `m` to type `Matcher<T>`.|
+|:------------------|:--------------------------------------|
+|`SafeMatcherCast<T>(m)`| [safely casts](CookBook.md#casting-matchers) matcher `m` to type `Matcher<T>`. |
+|`Truly(predicate)` |`predicate(argument)` returns something considered by C++ to be true, where `predicate` is a function or functor.|
+
+## Matchers as Predicates ##
+
+|`Matches(m)(value)`|evaluates to `true` if `value` matches `m`. You can use `Matches(m)` alone as a unary functor.|
+|:------------------|:---------------------------------------------------------------------------------------------|
+|`ExplainMatchResult(m, value, result_listener)`|evaluates to `true` if `value` matches `m`, explaining the result to `result_listener`. |
+|`Value(value, m)` |evaluates to `true` if `value` matches `m`. |
+
+## Defining Matchers ##
+
+| `MATCHER(IsEven, "") { return (arg % 2) == 0; }` | Defines a matcher `IsEven()` to match an even number. |
+|:-------------------------------------------------|:------------------------------------------------------|
+| `MATCHER_P(IsDivisibleBy, n, "") { *result_listener << "where the remainder is " << (arg % n); return (arg % n) == 0; }` | Defines a macher `IsDivisibleBy(n)` to match a number divisible by `n`. |
+| `MATCHER_P2(IsBetween, a, b, std::string(negation ? "isn't" : "is") + " between " + PrintToString(a) + " and " + PrintToString(b)) { return a <= arg && arg <= b; }` | Defines a matcher `IsBetween(a, b)` to match a value in the range [`a`, `b`]. |
+
+**Notes:**
+
+ 1. The `MATCHER*` macros cannot be used inside a function or class.
+ 1. The matcher body must be _purely functional_ (i.e. it cannot have any side effect, and the result must not depend on anything other than the value being matched and the matcher parameters).
+ 1. You can use `PrintToString(x)` to convert a value `x` of any type to a string.
+
+## Matchers as Test Assertions ##
+
+|`ASSERT_THAT(expression, m)`|Generates a [fatal failure](../../googletest/docs/Primer.md#assertions) if the value of `expression` doesn't match matcher `m`.|
+|:---------------------------|:----------------------------------------------------------------------------------------------------------------------------------------------|
+|`EXPECT_THAT(expression, m)`|Generates a non-fatal failure if the value of `expression` doesn't match matcher `m`. |
+
+# Actions #
+
+**Actions** specify what a mock function should do when invoked.
+
+## Returning a Value ##
+
+|`Return()`|Return from a `void` mock function.|
+|:---------|:----------------------------------|
+|`Return(value)`|Return `value`. If the type of `value` is different to the mock function's return type, `value` is converted to the latter type <i>at the time the expectation is set</i>, not when the action is executed.|
+|`ReturnArg<N>()`|Return the `N`-th (0-based) argument.|
+|`ReturnNew<T>(a1, ..., ak)`|Return `new T(a1, ..., ak)`; a different object is created each time.|
+|`ReturnNull()`|Return a null pointer. |
+|`ReturnPointee(ptr)`|Return the value pointed to by `ptr`.|
+|`ReturnRef(variable)`|Return a reference to `variable`. |
+|`ReturnRefOfCopy(value)`|Return a reference to a copy of `value`; the copy lives as long as the action.|
+
+## Side Effects ##
+
+|`Assign(&variable, value)`|Assign `value` to variable.|
+|:-------------------------|:--------------------------|
+| `DeleteArg<N>()` | Delete the `N`-th (0-based) argument, which must be a pointer. |
+| `SaveArg<N>(pointer)` | Save the `N`-th (0-based) argument to `*pointer`. |
+| `SaveArgPointee<N>(pointer)` | Save the value pointed to by the `N`-th (0-based) argument to `*pointer`. |
+| `SetArgReferee<N>(value)` | Assign value to the variable referenced by the `N`-th (0-based) argument. |
+|`SetArgPointee<N>(value)` |Assign `value` to the variable pointed by the `N`-th (0-based) argument.|
+|`SetArgumentPointee<N>(value)`|Same as `SetArgPointee<N>(value)`. Deprecated. Will be removed in v1.7.0.|
+|`SetArrayArgument<N>(first, last)`|Copies the elements in source range [`first`, `last`) to the array pointed to by the `N`-th (0-based) argument, which can be either a pointer or an iterator. The action does not take ownership of the elements in the source range.|
+|`SetErrnoAndReturn(error, value)`|Set `errno` to `error` and return `value`.|
+|`Throw(exception)` |Throws the given exception, which can be any copyable value. Available since v1.1.0.|
+
+## Using a Function or a Functor as an Action ##
+
+|`Invoke(f)`|Invoke `f` with the arguments passed to the mock function, where `f` can be a global/static function or a functor.|
+|:----------|:-----------------------------------------------------------------------------------------------------------------|
+|`Invoke(object_pointer, &class::method)`|Invoke the {method on the object with the arguments passed to the mock function. |
+|`InvokeWithoutArgs(f)`|Invoke `f`, which can be a global/static function or a functor. `f` must take no arguments. |
+|`InvokeWithoutArgs(object_pointer, &class::method)`|Invoke the method on the object, which takes no arguments. |
+|`InvokeArgument<N>(arg1, arg2, ..., argk)`|Invoke the mock function's `N`-th (0-based) argument, which must be a function or a functor, with the `k` arguments.|
+
+The return value of the invoked function is used as the return value
+of the action.
+
+When defining a function or functor to be used with `Invoke*()`, you can declare any unused parameters as `Unused`:
+```
+ double Distance(Unused, double x, double y) { return sqrt(x*x + y*y); }
+ ...
+ EXPECT_CALL(mock, Foo("Hi", _, _)).WillOnce(Invoke(Distance));
+```
+
+In `InvokeArgument<N>(...)`, if an argument needs to be passed by reference, wrap it inside `ByRef()`. For example,
+```
+ InvokeArgument<2>(5, string("Hi"), ByRef(foo))
+```
+calls the mock function's #2 argument, passing to it `5` and `string("Hi")` by value, and `foo` by reference.
+
+## Default Action ##
+
+|`DoDefault()`|Do the default action (specified by `ON_CALL()` or the built-in one).|
+|:------------|:--------------------------------------------------------------------|
+
+**Note:** due to technical reasons, `DoDefault()` cannot be used inside a composite action - trying to do so will result in a run-time error.
+
+## Composite Actions ##
+
+|`DoAll(a1, a2, ..., an)`|Do all actions `a1` to `an` and return the result of `an` in each invocation. The first `n - 1` sub-actions must return void. |
+|:-----------------------|:-----------------------------------------------------------------------------------------------------------------------------|
+|`IgnoreResult(a)` |Perform action `a` and ignore its result. `a` must not return void. |
+|`WithArg<N>(a)` |Pass the `N`-th (0-based) argument of the mock function to action `a` and perform it. |
+|`WithArgs<N1, N2, ..., Nk>(a)`|Pass the selected (0-based) arguments of the mock function to action `a` and perform it. |
+|`WithoutArgs(a)` |Perform action `a` without any arguments. |
+
+## Defining Actions ##
+
+| `ACTION(Sum) { return arg0 + arg1; }` | Defines an action `Sum()` to return the sum of the mock function's argument #0 and #1. |
+|:--------------------------------------|:---------------------------------------------------------------------------------------|
+| `ACTION_P(Plus, n) { return arg0 + n; }` | Defines an action `Plus(n)` to return the sum of the mock function's argument #0 and `n`. |
+| `ACTION_Pk(Foo, p1, ..., pk) { statements; }` | Defines a parameterized action `Foo(p1, ..., pk)` to execute the given `statements`. |
+
+The `ACTION*` macros cannot be used inside a function or class.
+
+# Cardinalities #
+
+These are used in `Times()` to specify how many times a mock function will be called:
+
+|`AnyNumber()`|The function can be called any number of times.|
+|:------------|:----------------------------------------------|
+|`AtLeast(n)` |The call is expected at least `n` times. |
+|`AtMost(n)` |The call is expected at most `n` times. |
+|`Between(m, n)`|The call is expected between `m` and `n` (inclusive) times.|
+|`Exactly(n) or n`|The call is expected exactly `n` times. In particular, the call should never happen when `n` is 0.|
+
+# Expectation Order #
+
+By default, the expectations can be matched in _any_ order. If some
+or all expectations must be matched in a given order, there are two
+ways to specify it. They can be used either independently or
+together.
+
+## The After Clause ##
+
+```
+using ::testing::Expectation;
+...
+Expectation init_x = EXPECT_CALL(foo, InitX());
+Expectation init_y = EXPECT_CALL(foo, InitY());
+EXPECT_CALL(foo, Bar())
+ .After(init_x, init_y);
+```
+says that `Bar()` can be called only after both `InitX()` and
+`InitY()` have been called.
+
+If you don't know how many pre-requisites an expectation has when you
+write it, you can use an `ExpectationSet` to collect them:
+
+```
+using ::testing::ExpectationSet;
+...
+ExpectationSet all_inits;
+for (int i = 0; i < element_count; i++) {
+ all_inits += EXPECT_CALL(foo, InitElement(i));
+}
+EXPECT_CALL(foo, Bar())
+ .After(all_inits);
+```
+says that `Bar()` can be called only after all elements have been
+initialized (but we don't care about which elements get initialized
+before the others).
+
+Modifying an `ExpectationSet` after using it in an `.After()` doesn't
+affect the meaning of the `.After()`.
+
+## Sequences ##
+
+When you have a long chain of sequential expectations, it's easier to
+specify the order using **sequences**, which don't require you to given
+each expectation in the chain a different name. <i>All expected<br>
+calls</i> in the same sequence must occur in the order they are
+specified.
+
+```
+using ::testing::Sequence;
+Sequence s1, s2;
+...
+EXPECT_CALL(foo, Reset())
+ .InSequence(s1, s2)
+ .WillOnce(Return(true));
+EXPECT_CALL(foo, GetSize())
+ .InSequence(s1)
+ .WillOnce(Return(1));
+EXPECT_CALL(foo, Describe(A<const char*>()))
+ .InSequence(s2)
+ .WillOnce(Return("dummy"));
+```
+says that `Reset()` must be called before _both_ `GetSize()` _and_
+`Describe()`, and the latter two can occur in any order.
+
+To put many expectations in a sequence conveniently:
+```
+using ::testing::InSequence;
+{
+ InSequence dummy;
+
+ EXPECT_CALL(...)...;
+ EXPECT_CALL(...)...;
+ ...
+ EXPECT_CALL(...)...;
+}
+```
+says that all expected calls in the scope of `dummy` must occur in
+strict order. The name `dummy` is irrelevant.)
+
+# Verifying and Resetting a Mock #
+
+Google Mock will verify the expectations on a mock object when it is destructed, or you can do it earlier:
+```
+using ::testing::Mock;
+...
+// Verifies and removes the expectations on mock_obj;
+// returns true iff successful.
+Mock::VerifyAndClearExpectations(&mock_obj);
+...
+// Verifies and removes the expectations on mock_obj;
+// also removes the default actions set by ON_CALL();
+// returns true iff successful.
+Mock::VerifyAndClear(&mock_obj);
+```
+
+You can also tell Google Mock that a mock object can be leaked and doesn't
+need to be verified:
+```
+Mock::AllowLeak(&mock_obj);
+```
+
+# Mock Classes #
+
+Google Mock defines a convenient mock class template
+```
+class MockFunction<R(A1, ..., An)> {
+ public:
+ MOCK_METHODn(Call, R(A1, ..., An));
+};
+```
+See this [recipe](CookBook.md#using-check-points) for one application of it.
+
+# Flags #
+
+| `--gmock_catch_leaked_mocks=0` | Don't report leaked mock objects as failures. |
+|:-------------------------------|:----------------------------------------------|
+| `--gmock_verbose=LEVEL` | Sets the default verbosity level (`info`, `warning`, or `error`) of Google Mock messages. |