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17//
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27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30// Implements class templates NiceMock, NaggyMock, and StrictMock.
31//
32// Given a mock class MockFoo that is created using Google Mock,
33// NiceMock<MockFoo> is a subclass of MockFoo that allows
34// uninteresting calls (i.e. calls to mock methods that have no
35// EXPECT_CALL specs), NaggyMock<MockFoo> is a subclass of MockFoo
36// that prints a warning when an uninteresting call occurs, and
37// StrictMock<MockFoo> is a subclass of MockFoo that treats all
38// uninteresting calls as errors.
39//
40// Currently a mock is naggy by default, so MockFoo and
41// NaggyMock<MockFoo> behave like the same. However, we will soon
42// switch the default behavior of mocks to be nice, as that in general
43// leads to more maintainable tests. When that happens, MockFoo will
44// stop behaving like NaggyMock<MockFoo> and start behaving like
45// NiceMock<MockFoo>.
46//
47// NiceMock, NaggyMock, and StrictMock "inherit" the constructors of
48// their respective base class. Therefore you can write
49// NiceMock<MockFoo>(5, "a") to construct a nice mock where MockFoo
50// has a constructor that accepts (int, const char*), for example.
51//
52// A known limitation is that NiceMock<MockFoo>, NaggyMock<MockFoo>,
53// and StrictMock<MockFoo> only works for mock methods defined using
54// the MOCK_METHOD* family of macros DIRECTLY in the MockFoo class.
55// If a mock method is defined in a base class of MockFoo, the "nice"
56// or "strict" modifier may not affect it, depending on the compiler.
57// In particular, nesting NiceMock, NaggyMock, and StrictMock is NOT
58// supported.
59
60// IWYU pragma: private, include "gmock/gmock.h"
61// IWYU pragma: friend gmock/.*
62
63#ifndef GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_NICE_STRICT_H_
64#define GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_NICE_STRICT_H_
65
66#include <cstdint>
67#include <type_traits>
68
69#include "gmock/gmock-spec-builders.h"
70#include "gmock/internal/gmock-port.h"
71
72namespace testing {
73template <class MockClass>
74class NiceMock;
75template <class MockClass>
76class NaggyMock;
77template <class MockClass>
78class StrictMock;
79
80namespace internal {
81template <typename T>
82std::true_type StrictnessModifierProbe(const NiceMock<T>&);
83template <typename T>
84std::true_type StrictnessModifierProbe(const NaggyMock<T>&);
85template <typename T>
86std::true_type StrictnessModifierProbe(const StrictMock<T>&);
87std::false_type StrictnessModifierProbe(...);
88
89template <typename T>
90constexpr bool HasStrictnessModifier() {
91 return decltype(StrictnessModifierProbe(std::declval<const T&>()))::value;
92}
93
94// Base classes that register and deregister with testing::Mock to alter the
95// default behavior around uninteresting calls. Inheriting from one of these
96// classes first and then MockClass ensures the MockClass constructor is run
97// after registration, and that the MockClass destructor runs before
98// deregistration. This guarantees that MockClass's constructor and destructor
99// run with the same level of strictness as its instance methods.
100
101#if GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_MINGW && \
102 (defined(_MSC_VER) || defined(__clang__))
103// We need to mark these classes with this declspec to ensure that
104// the empty base class optimization is performed.
105#define GTEST_INTERNAL_EMPTY_BASE_CLASS __declspec(empty_bases)
106#else
107#define GTEST_INTERNAL_EMPTY_BASE_CLASS
108#endif
109
110template <typename Base>
111class NiceMockImpl {
112 public:
113 NiceMockImpl() {
114 ::testing::Mock::AllowUninterestingCalls(mock_obj: reinterpret_cast<uintptr_t>(this));
115 }
116
117 ~NiceMockImpl() {
118 ::testing::Mock::UnregisterCallReaction(mock_obj: reinterpret_cast<uintptr_t>(this));
119 }
120};
121
122template <typename Base>
123class NaggyMockImpl {
124 public:
125 NaggyMockImpl() {
126 ::testing::Mock::WarnUninterestingCalls(mock_obj: reinterpret_cast<uintptr_t>(this));
127 }
128
129 ~NaggyMockImpl() {
130 ::testing::Mock::UnregisterCallReaction(mock_obj: reinterpret_cast<uintptr_t>(this));
131 }
132};
133
134template <typename Base>
135class StrictMockImpl {
136 public:
137 StrictMockImpl() {
138 ::testing::Mock::FailUninterestingCalls(mock_obj: reinterpret_cast<uintptr_t>(this));
139 }
140
141 ~StrictMockImpl() {
142 ::testing::Mock::UnregisterCallReaction(mock_obj: reinterpret_cast<uintptr_t>(this));
143 }
144};
145
146} // namespace internal
147
148template <class MockClass>
149class GTEST_INTERNAL_EMPTY_BASE_CLASS NiceMock
150 : private internal::NiceMockImpl<MockClass>,
151 public MockClass {
152 public:
153 static_assert(!internal::HasStrictnessModifier<MockClass>(),
154 "Can't apply NiceMock to a class hierarchy that already has a "
155 "strictness modifier. See "
156 "https://google.github.io/googletest/"
157 "gmock_cook_book.html#NiceStrictNaggy");
158 NiceMock() : MockClass() {
159 static_assert(sizeof(*this) == sizeof(MockClass),
160 "The impl subclass shouldn't introduce any padding");
161 }
162
163 // Ideally, we would inherit base class's constructors through a using
164 // declaration, which would preserve their visibility. However, many existing
165 // tests rely on the fact that current implementation reexports protected
166 // constructors as public. These tests would need to be cleaned up first.
167
168 // Single argument constructor is special-cased so that it can be
169 // made explicit.
170 template <typename A>
171 explicit NiceMock(A&& arg) : MockClass(std::forward<A>(arg)) {
172 static_assert(sizeof(*this) == sizeof(MockClass),
173 "The impl subclass shouldn't introduce any padding");
174 }
175
176 template <typename TArg1, typename TArg2, typename... An>
177 NiceMock(TArg1&& arg1, TArg2&& arg2, An&&... args)
178 : MockClass(std::forward<TArg1>(arg1), std::forward<TArg2>(arg2),
179 std::forward<An>(args)...) {
180 static_assert(sizeof(*this) == sizeof(MockClass),
181 "The impl subclass shouldn't introduce any padding");
182 }
183
184 private:
185 NiceMock(const NiceMock&) = delete;
186 NiceMock& operator=(const NiceMock&) = delete;
187};
188
189template <class MockClass>
190class GTEST_INTERNAL_EMPTY_BASE_CLASS NaggyMock
191 : private internal::NaggyMockImpl<MockClass>,
192 public MockClass {
193 static_assert(!internal::HasStrictnessModifier<MockClass>(),
194 "Can't apply NaggyMock to a class hierarchy that already has a "
195 "strictness modifier. See "
196 "https://google.github.io/googletest/"
197 "gmock_cook_book.html#NiceStrictNaggy");
198
199 public:
200 NaggyMock() : MockClass() {
201 static_assert(sizeof(*this) == sizeof(MockClass),
202 "The impl subclass shouldn't introduce any padding");
203 }
204
205 // Ideally, we would inherit base class's constructors through a using
206 // declaration, which would preserve their visibility. However, many existing
207 // tests rely on the fact that current implementation reexports protected
208 // constructors as public. These tests would need to be cleaned up first.
209
210 // Single argument constructor is special-cased so that it can be
211 // made explicit.
212 template <typename A>
213 explicit NaggyMock(A&& arg) : MockClass(std::forward<A>(arg)) {
214 static_assert(sizeof(*this) == sizeof(MockClass),
215 "The impl subclass shouldn't introduce any padding");
216 }
217
218 template <typename TArg1, typename TArg2, typename... An>
219 NaggyMock(TArg1&& arg1, TArg2&& arg2, An&&... args)
220 : MockClass(std::forward<TArg1>(arg1), std::forward<TArg2>(arg2),
221 std::forward<An>(args)...) {
222 static_assert(sizeof(*this) == sizeof(MockClass),
223 "The impl subclass shouldn't introduce any padding");
224 }
225
226 private:
227 NaggyMock(const NaggyMock&) = delete;
228 NaggyMock& operator=(const NaggyMock&) = delete;
229};
230
231template <class MockClass>
232class GTEST_INTERNAL_EMPTY_BASE_CLASS StrictMock
233 : private internal::StrictMockImpl<MockClass>,
234 public MockClass {
235 public:
236 static_assert(
237 !internal::HasStrictnessModifier<MockClass>(),
238 "Can't apply StrictMock to a class hierarchy that already has a "
239 "strictness modifier. See "
240 "https://google.github.io/googletest/"
241 "gmock_cook_book.html#NiceStrictNaggy");
242 StrictMock() : MockClass() {
243 static_assert(sizeof(*this) == sizeof(MockClass),
244 "The impl subclass shouldn't introduce any padding");
245 }
246
247 // Ideally, we would inherit base class's constructors through a using
248 // declaration, which would preserve their visibility. However, many existing
249 // tests rely on the fact that current implementation reexports protected
250 // constructors as public. These tests would need to be cleaned up first.
251
252 // Single argument constructor is special-cased so that it can be
253 // made explicit.
254 template <typename A>
255 explicit StrictMock(A&& arg) : MockClass(std::forward<A>(arg)) {
256 static_assert(sizeof(*this) == sizeof(MockClass),
257 "The impl subclass shouldn't introduce any padding");
258 }
259
260 template <typename TArg1, typename TArg2, typename... An>
261 StrictMock(TArg1&& arg1, TArg2&& arg2, An&&... args)
262 : MockClass(std::forward<TArg1>(arg1), std::forward<TArg2>(arg2),
263 std::forward<An>(args)...) {
264 static_assert(sizeof(*this) == sizeof(MockClass),
265 "The impl subclass shouldn't introduce any padding");
266 }
267
268 private:
269 StrictMock(const StrictMock&) = delete;
270 StrictMock& operator=(const StrictMock&) = delete;
271};
272
273#undef GTEST_INTERNAL_EMPTY_BASE_CLASS
274
275} // namespace testing
276
277#endif // GOOGLEMOCK_INCLUDE_GMOCK_GMOCK_NICE_STRICT_H_
278