TestBinarySearch.cpp (5619B)
1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */ 3 /* This Source Code Form is subject to the terms of the Mozilla Public 4 * License, v. 2.0. If a copy of the MPL was not distributed with this file, 5 * You can obtain one at http://mozilla.org/MPL/2.0/. */ 6 7 #include "mozilla/Assertions.h" 8 #include "mozilla/BinarySearch.h" 9 #include "mozilla/Vector.h" 10 11 #include <cstdlib> 12 13 using mozilla::BinarySearch; 14 using mozilla::BinarySearchIf; 15 using mozilla::Vector; 16 17 #define A(a) MOZ_RELEASE_ASSERT(a) 18 19 struct Person { 20 int mAge; 21 int mId; 22 Person(int aAge, int aId) : mAge(aAge), mId(aId) {} 23 }; 24 25 struct GetAge { 26 Vector<Person>& mV; 27 explicit GetAge(Vector<Person>& aV) : mV(aV) {} 28 int operator[](size_t index) const { return mV[index].mAge; } 29 }; 30 31 struct RangeFinder { 32 const int mLower, mUpper; 33 RangeFinder(int lower, int upper) : mLower(lower), mUpper(upper) {} 34 int operator()(int val) const { 35 if (val >= mUpper) return -1; 36 if (val < mLower) return 1; 37 return 0; 38 } 39 }; 40 41 static void TestBinarySearch() { 42 size_t m; 43 44 Vector<int> v1; 45 MOZ_RELEASE_ASSERT(v1.append(2)); 46 MOZ_RELEASE_ASSERT(v1.append(4)); 47 MOZ_RELEASE_ASSERT(v1.append(6)); 48 MOZ_RELEASE_ASSERT(v1.append(8)); 49 50 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 1, &m) && m == 0); 51 MOZ_RELEASE_ASSERT(BinarySearch(v1, 0, v1.length(), 2, &m) && m == 0); 52 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 3, &m) && m == 1); 53 MOZ_RELEASE_ASSERT(BinarySearch(v1, 0, v1.length(), 4, &m) && m == 1); 54 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 5, &m) && m == 2); 55 MOZ_RELEASE_ASSERT(BinarySearch(v1, 0, v1.length(), 6, &m) && m == 2); 56 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 7, &m) && m == 3); 57 MOZ_RELEASE_ASSERT(BinarySearch(v1, 0, v1.length(), 8, &m) && m == 3); 58 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 9, &m) && m == 4); 59 60 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 1, &m) && m == 1); 61 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 2, &m) && m == 1); 62 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 3, &m) && m == 1); 63 MOZ_RELEASE_ASSERT(BinarySearch(v1, 1, 3, 4, &m) && m == 1); 64 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 5, &m) && m == 2); 65 MOZ_RELEASE_ASSERT(BinarySearch(v1, 1, 3, 6, &m) && m == 2); 66 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 7, &m) && m == 3); 67 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 8, &m) && m == 3); 68 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 9, &m) && m == 3); 69 70 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, 0, 0, &m) && m == 0); 71 MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, 0, 9, &m) && m == 0); 72 73 Vector<int> v2; 74 MOZ_RELEASE_ASSERT(!BinarySearch(v2, 0, 0, 0, &m) && m == 0); 75 MOZ_RELEASE_ASSERT(!BinarySearch(v2, 0, 0, 9, &m) && m == 0); 76 77 Vector<Person> v3; 78 MOZ_RELEASE_ASSERT(v3.append(Person(2, 42))); 79 MOZ_RELEASE_ASSERT(v3.append(Person(4, 13))); 80 MOZ_RELEASE_ASSERT(v3.append(Person(6, 360))); 81 82 A(!BinarySearch(GetAge(v3), 0, v3.length(), 1, &m) && m == 0); 83 A(BinarySearch(GetAge(v3), 0, v3.length(), 2, &m) && m == 0); 84 A(!BinarySearch(GetAge(v3), 0, v3.length(), 3, &m) && m == 1); 85 A(BinarySearch(GetAge(v3), 0, v3.length(), 4, &m) && m == 1); 86 A(!BinarySearch(GetAge(v3), 0, v3.length(), 5, &m) && m == 2); 87 A(BinarySearch(GetAge(v3), 0, v3.length(), 6, &m) && m == 2); 88 A(!BinarySearch(GetAge(v3), 0, v3.length(), 7, &m) && m == 3); 89 } 90 91 static void TestBinarySearchIf() { 92 const int v1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; 93 const size_t len = std::size(v1); 94 size_t m; 95 96 A(BinarySearchIf(v1, 0, len, RangeFinder(2, 3), &m) && m == 2); 97 A(!BinarySearchIf(v1, 0, len, RangeFinder(-5, -2), &m) && m == 0); 98 A(BinarySearchIf(v1, 0, len, RangeFinder(3, 5), &m) && m >= 3 && m < 5); 99 A(!BinarySearchIf(v1, 0, len, RangeFinder(10, 12), &m) && m == 10); 100 } 101 102 static void TestEqualRange() { 103 struct CompareN { 104 int mVal; 105 explicit CompareN(int n) : mVal(n) {} 106 int operator()(int aVal) const { return mVal - aVal; } 107 }; 108 109 constexpr int kMaxNumber = 100; 110 constexpr int kMaxRepeat = 2; 111 112 Vector<int> sortedArray; 113 MOZ_RELEASE_ASSERT(sortedArray.reserve(kMaxNumber * kMaxRepeat)); 114 115 // Make a sorted array by appending the loop counter [0, kMaxRepeat] times 116 // in each iteration. The array will be something like: 117 // [0, 0, 1, 1, 2, 2, 8, 9, ..., kMaxNumber] 118 for (int i = 0; i <= kMaxNumber; ++i) { 119 int repeat = rand() % (kMaxRepeat + 1); 120 for (int j = 0; j < repeat; ++j) { 121 MOZ_RELEASE_ASSERT(sortedArray.emplaceBack(i)); 122 } 123 } 124 125 for (int i = -1; i < kMaxNumber + 1; ++i) { 126 auto bounds = EqualRange(sortedArray, 0, sortedArray.length(), CompareN(i)); 127 128 MOZ_RELEASE_ASSERT(bounds.first <= sortedArray.length()); 129 MOZ_RELEASE_ASSERT(bounds.second <= sortedArray.length()); 130 MOZ_RELEASE_ASSERT(bounds.first <= bounds.second); 131 132 if (bounds.first == 0) { 133 MOZ_RELEASE_ASSERT(sortedArray[0] >= i); 134 } else if (bounds.first == sortedArray.length()) { 135 MOZ_RELEASE_ASSERT(sortedArray[sortedArray.length() - 1] < i); 136 } else { 137 MOZ_RELEASE_ASSERT(sortedArray[bounds.first - 1] < i); 138 MOZ_RELEASE_ASSERT(sortedArray[bounds.first] >= i); 139 } 140 141 if (bounds.second == 0) { 142 MOZ_RELEASE_ASSERT(sortedArray[0] > i); 143 } else if (bounds.second == sortedArray.length()) { 144 MOZ_RELEASE_ASSERT(sortedArray[sortedArray.length() - 1] <= i); 145 } else { 146 MOZ_RELEASE_ASSERT(sortedArray[bounds.second - 1] <= i); 147 MOZ_RELEASE_ASSERT(sortedArray[bounds.second] > i); 148 } 149 } 150 } 151 152 int main() { 153 TestBinarySearch(); 154 TestBinarySearchIf(); 155 TestEqualRange(); 156 return 0; 157 }