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1// Copyright 2005, Google Inc.2// All rights reserved.3//4// Redistribution and use in source and binary forms, with or without5// modification, are permitted provided that the following conditions are6// met:7//8// * Redistributions of source code must retain the above copyright9// notice, this list of conditions and the following disclaimer.10// * Redistributions in binary form must reproduce the above11// copyright notice, this list of conditions and the following disclaimer12// in the documentation and/or other materials provided with the13// distribution.14// * Neither the name of Google Inc. nor the names of its15// contributors may be used to endorse or promote products derived from16// this software without specific prior written permission.17//18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.29 30// The Google C++ Testing and Mocking Framework (Google Test)31//32// This file implements the AssertionResult type.33 34// IWYU pragma: private, include "gtest/gtest.h"35// IWYU pragma: friend gtest/.*36// IWYU pragma: friend gmock/.*37 38#ifndef GOOGLETEST_INCLUDE_GTEST_GTEST_ASSERTION_RESULT_H_39#define GOOGLETEST_INCLUDE_GTEST_GTEST_ASSERTION_RESULT_H_40 41#include <memory>42#include <ostream>43#include <string>44#include <type_traits>45 46#include "gtest/gtest-message.h"47#include "gtest/internal/gtest-port.h"48 49GTEST_DISABLE_MSC_WARNINGS_PUSH_(4251 \50/* class A needs to have dll-interface to be used by clients of class B */)51 52namespace testing {53 54// A class for indicating whether an assertion was successful. When55// the assertion wasn't successful, the AssertionResult object56// remembers a non-empty message that describes how it failed.57//58// To create an instance of this class, use one of the factory functions59// (AssertionSuccess() and AssertionFailure()).60//61// This class is useful for two purposes:62// 1. Defining predicate functions to be used with Boolean test assertions63// EXPECT_TRUE/EXPECT_FALSE and their ASSERT_ counterparts64// 2. Defining predicate-format functions to be65// used with predicate assertions (ASSERT_PRED_FORMAT*, etc).66//67// For example, if you define IsEven predicate:68//69// testing::AssertionResult IsEven(int n) {70// if ((n % 2) == 0)71// return testing::AssertionSuccess();72// else73// return testing::AssertionFailure() << n << " is odd";74// }75//76// Then the failed expectation EXPECT_TRUE(IsEven(Fib(5)))77// will print the message78//79// Value of: IsEven(Fib(5))80// Actual: false (5 is odd)81// Expected: true82//83// instead of a more opaque84//85// Value of: IsEven(Fib(5))86// Actual: false87// Expected: true88//89// in case IsEven is a simple Boolean predicate.90//91// If you expect your predicate to be reused and want to support informative92// messages in EXPECT_FALSE and ASSERT_FALSE (negative assertions show up93// about half as often as positive ones in our tests), supply messages for94// both success and failure cases:95//96// testing::AssertionResult IsEven(int n) {97// if ((n % 2) == 0)98// return testing::AssertionSuccess() << n << " is even";99// else100// return testing::AssertionFailure() << n << " is odd";101// }102//103// Then a statement EXPECT_FALSE(IsEven(Fib(6))) will print104//105// Value of: IsEven(Fib(6))106// Actual: true (8 is even)107// Expected: false108//109// NB: Predicates that support negative Boolean assertions have reduced110// performance in positive ones so be careful not to use them in tests111// that have lots (tens of thousands) of positive Boolean assertions.112//113// To use this class with EXPECT_PRED_FORMAT assertions such as:114//115// // Verifies that Foo() returns an even number.116// EXPECT_PRED_FORMAT1(IsEven, Foo());117//118// you need to define:119//120// testing::AssertionResult IsEven(const char* expr, int n) {121// if ((n % 2) == 0)122// return testing::AssertionSuccess();123// else124// return testing::AssertionFailure()125// << "Expected: " << expr << " is even\n Actual: it's " << n;126// }127//128// If Foo() returns 5, you will see the following message:129//130// Expected: Foo() is even131// Actual: it's 5132//133class GTEST_API_ AssertionResult {134 public:135 // Copy constructor.136 // Used in EXPECT_TRUE/FALSE(assertion_result).137 AssertionResult(const AssertionResult& other);138 139// C4800 is a level 3 warning in Visual Studio 2015 and earlier.140// This warning is not emitted in Visual Studio 2017.141// This warning is off by default starting in Visual Studio 2019 but can be142// enabled with command-line options.143#if defined(_MSC_VER) && (_MSC_VER < 1910 || _MSC_VER >= 1920)144 GTEST_DISABLE_MSC_WARNINGS_PUSH_(4800 /* forcing value to bool */)145#endif146 147 // Used in the EXPECT_TRUE/FALSE(bool_expression).148 //149 // T must be contextually convertible to bool.150 //151 // The second parameter prevents this overload from being considered if152 // the argument is implicitly convertible to AssertionResult. In that case153 // we want AssertionResult's copy constructor to be used.154 template <typename T>155 explicit AssertionResult(156 const T& success,157 typename std::enable_if<158 !std::is_convertible<T, AssertionResult>::value>::type*159 /*enabler*/160 = nullptr)161 : success_(success) {}162 163#if defined(_MSC_VER) && (_MSC_VER < 1910 || _MSC_VER >= 1920)164 GTEST_DISABLE_MSC_WARNINGS_POP_()165#endif166 167 // Assignment operator.168 AssertionResult& operator=(AssertionResult other) {169 swap(other);170 return *this;171 }172 173 // Returns true if and only if the assertion succeeded.174 operator bool() const { return success_; } // NOLINT175 176 // Returns the assertion's negation. Used with EXPECT/ASSERT_FALSE.177 AssertionResult operator!() const;178 179 // Returns the text streamed into this AssertionResult. Test assertions180 // use it when they fail (i.e., the predicate's outcome doesn't match the181 // assertion's expectation). When nothing has been streamed into the182 // object, returns an empty string.183 const char* message() const {184 return message_ != nullptr ? message_->c_str() : "";185 }186 // Deprecated; please use message() instead.187 const char* failure_message() const { return message(); }188 189 // Streams a custom failure message into this object.190 template <typename T>191 AssertionResult& operator<<(const T& value) {192 AppendMessage(Message() << value);193 return *this;194 }195 196 // Allows streaming basic output manipulators such as endl or flush into197 // this object.198 AssertionResult& operator<<(199 ::std::ostream& (*basic_manipulator)(::std::ostream& stream)) {200 AppendMessage(Message() << basic_manipulator);201 return *this;202 }203 204 private:205 // Appends the contents of message to message_.206 void AppendMessage(const Message& a_message) {207 if (message_ == nullptr) message_ = ::std::make_unique<::std::string>();208 message_->append(a_message.GetString().c_str());209 }210 211 // Swap the contents of this AssertionResult with other.212 void swap(AssertionResult& other);213 214 // Stores result of the assertion predicate.215 bool success_;216 // Stores the message describing the condition in case the expectation217 // construct is not satisfied with the predicate's outcome.218 // Referenced via a pointer to avoid taking too much stack frame space219 // with test assertions.220 std::unique_ptr< ::std::string> message_;221};222 223// Makes a successful assertion result.224GTEST_API_ AssertionResult AssertionSuccess();225 226// Makes a failed assertion result.227GTEST_API_ AssertionResult AssertionFailure();228 229// Makes a failed assertion result with the given failure message.230// Deprecated; use AssertionFailure() << msg.231GTEST_API_ AssertionResult AssertionFailure(const Message& msg);232 233} // namespace testing234 235GTEST_DISABLE_MSC_WARNINGS_POP_() // 4251236 237#endif // GOOGLETEST_INCLUDE_GTEST_GTEST_ASSERTION_RESULT_H_238