1// Copyright 2009 Google Inc. All Rights Reserved. 2// 3// Redistribution and use in source and binary forms, with or without 4// modification, are permitted provided that the following conditions are 5// met: 6// 7// * Redistributions of source code must retain the above copyright 8// notice, this list of conditions and the following disclaimer. 9// * Redistributions in binary form must reproduce the above 10// copyright notice, this list of conditions and the following disclaimer 11// in the documentation and/or other materials provided with the 12// distribution. 13// * Neither the name of Google Inc. nor the names of its 14// contributors may be used to endorse or promote products derived from 15// this software without specific prior written permission. 16// 17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 21// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 29 30// This sample shows how to use Google Test listener API to implement 31// a primitive leak checker. 32 33#include <stdio.h> 34#include <stdlib.h> 35 36#include "gtest/gtest.h" 37using ::testing::EmptyTestEventListener; 38using ::testing::InitGoogleTest; 39using ::testing::Test; 40using ::testing::TestEventListeners; 41using ::testing::TestInfo; 42using ::testing::TestPartResult; 43using ::testing::UnitTest; 44 45namespace { 46// We will track memory used by this class. 47class Water { 48 public: 49 // Normal Water declarations go here. 50 51 // operator new and operator delete help us control water allocation. 52 void* operator new(size_t allocation_size) { 53 allocated_++; 54 return malloc(allocation_size); 55 } 56 57 void operator delete(void* block, size_t /* allocation_size */) { 58 allocated_--; 59 free(block); 60 } 61 62 static int allocated() { return allocated_; } 63 64 private: 65 static int allocated_; 66}; 67 68int Water::allocated_ = 0; 69 70// This event listener monitors how many Water objects are created and 71// destroyed by each test, and reports a failure if a test leaks some Water 72// objects. It does this by comparing the number of live Water objects at 73// the beginning of a test and at the end of a test. 74class LeakChecker : public EmptyTestEventListener { 75 private: 76 // Called before a test starts. 77 virtual void OnTestStart(const TestInfo& /* test_info */) { 78 initially_allocated_ = Water::allocated(); 79 } 80 81 // Called after a test ends. 82 virtual void OnTestEnd(const TestInfo& /* test_info */) { 83 int difference = Water::allocated() - initially_allocated_; 84 85 // You can generate a failure in any event handler except 86 // OnTestPartResult. Just use an appropriate Google Test assertion to do 87 // it. 88 EXPECT_LE(difference, 0) << "Leaked " << difference << " unit(s) of Water!"; 89 } 90 91 int initially_allocated_; 92}; 93 94TEST(ListenersTest, DoesNotLeak) { 95 Water* water = new Water; 96 delete water; 97} 98 99// This should fail when the --check_for_leaks command line flag is 100// specified. 101TEST(ListenersTest, LeaksWater) { 102 Water* water = new Water; 103 EXPECT_TRUE(water != NULL); 104} 105} // namespace 106 107int main(int argc, char **argv) { 108 InitGoogleTest(&argc, argv); 109 110 bool check_for_leaks = false; 111 if (argc > 1 && strcmp(argv[1], "--check_for_leaks") == 0 ) 112 check_for_leaks = true; 113 else 114 printf("%s\n", "Run this program with --check_for_leaks to enable " 115 "custom leak checking in the tests."); 116 117 // If we are given the --check_for_leaks command line flag, installs the 118 // leak checker. 119 if (check_for_leaks) { 120 TestEventListeners& listeners = UnitTest::GetInstance()->listeners(); 121 122 // Adds the leak checker to the end of the test event listener list, 123 // after the default text output printer and the default XML report 124 // generator. 125 // 126 // The order is important - it ensures that failures generated in the 127 // leak checker's OnTestEnd() method are processed by the text and XML 128 // printers *before* their OnTestEnd() methods are called, such that 129 // they are attributed to the right test. Remember that a listener 130 // receives an OnXyzStart event *after* listeners preceding it in the 131 // list received that event, and receives an OnXyzEnd event *before* 132 // listeners preceding it. 133 // 134 // We don't need to worry about deleting the new listener later, as 135 // Google Test will do it. 136 listeners.Append(new LeakChecker); 137 } 138 return RUN_ALL_TESTS(); 139} 140