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 // Author: vladl (at) google.com (Vlad Losev) 30 31 // This sample shows how to use Google Test listener API to implement 32 // a primitive leak checker. 33 34 #include <stdio.h> 35 #include <stdlib.h> 36 37 #include "gtest/gtest.h" 38 39 using ::testing::EmptyTestEventListener; 40 using ::testing::InitGoogleTest; 41 using ::testing::Test; 42 using ::testing::TestCase; 43 using ::testing::TestEventListeners; 44 using ::testing::TestInfo; 45 using ::testing::TestPartResult; 46 using ::testing::UnitTest; 47 48 namespace { 49 50 // We will track memory used by this class. 51 class Water { 52 public: 53 // Normal Water declarations go here. 54 55 // operator new and operator delete help us control water allocation. 56 void* operator new(size_t allocation_size) { 57 allocated_++; 58 return malloc(allocation_size); 59 } 60 61 void operator delete(void* block, size_t /* allocation_size */) { 62 allocated_--; 63 free(block); 64 } 65 66 static int allocated() { return allocated_; } 67 68 private: 69 static int allocated_; 70 }; 71 72 int Water::allocated_ = 0; 73 74 // This event listener monitors how many Water objects are created and 75 // destroyed by each test, and reports a failure if a test leaks some Water 76 // objects. It does this by comparing the number of live Water objects at 77 // the beginning of a test and at the end of a test. 78 class LeakChecker : public EmptyTestEventListener { 79 private: 80 // Called before a test starts. 81 virtual void OnTestStart(const TestInfo& /* test_info */) { 82 initially_allocated_ = Water::allocated(); 83 } 84 85 // Called after a test ends. 86 virtual void OnTestEnd(const TestInfo& /* test_info */) { 87 int difference = Water::allocated() - initially_allocated_; 88 89 // You can generate a failure in any event handler except 90 // OnTestPartResult. Just use an appropriate Google Test assertion to do 91 // it. 92 EXPECT_LE(difference, 0) << "Leaked " << difference << " unit(s) of Water!"; 93 } 94 95 int initially_allocated_; 96 }; 97 98 TEST(ListenersTest, DoesNotLeak) { 99 Water* water = new Water; 100 delete water; 101 } 102 103 // This should fail when the --check_for_leaks command line flag is 104 // specified. 105 TEST(ListenersTest, LeaksWater) { 106 Water* water = new Water; 107 EXPECT_TRUE(water != NULL); 108 } 109 110 } // namespace 111 112 int main(int argc, char **argv) { 113 InitGoogleTest(&argc, argv); 114 115 bool check_for_leaks = false; 116 if (argc > 1 && strcmp(argv[1], "--check_for_leaks") == 0 ) 117 check_for_leaks = true; 118 else 119 printf("%s\n", "Run this program with --check_for_leaks to enable " 120 "custom leak checking in the tests."); 121 122 // If we are given the --check_for_leaks command line flag, installs the 123 // leak checker. 124 if (check_for_leaks) { 125 TestEventListeners& listeners = UnitTest::GetInstance()->listeners(); 126 127 // Adds the leak checker to the end of the test event listener list, 128 // after the default text output printer and the default XML report 129 // generator. 130 // 131 // The order is important - it ensures that failures generated in the 132 // leak checker's OnTestEnd() method are processed by the text and XML 133 // printers *before* their OnTestEnd() methods are called, such that 134 // they are attributed to the right test. Remember that a listener 135 // receives an OnXyzStart event *after* listeners preceding it in the 136 // list received that event, and receives an OnXyzEnd event *before* 137 // listeners preceding it. 138 // 139 // We don't need to worry about deleting the new listener later, as 140 // Google Test will do it. 141 listeners.Append(new LeakChecker); 142 } 143 return RUN_ALL_TESTS(); 144 } 145
