170 lines · cpp
1//===-- Unittests for strncmp ---------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "src/string/strncmp.h"10#include "test/UnitTest/Test.h"11 12// This group is just copies of the strcmp tests, since all the same cases still13// need to be tested.14 15TEST(LlvmLibcStrNCmpTest, EmptyStringsShouldReturnZeroWithSufficientLength) {16 const char *s1 = "";17 const char *s2 = "";18 int result = LIBC_NAMESPACE::strncmp(s1, s2, 1);19 ASSERT_EQ(result, 0);20 21 // Verify operands reversed.22 result = LIBC_NAMESPACE::strncmp(s2, s1, 1);23 ASSERT_EQ(result, 0);24}25 26TEST(LlvmLibcStrNCmpTest,27 EmptyStringShouldNotEqualNonEmptyStringWithSufficientLength) {28 const char *empty = "";29 const char *s2 = "abc";30 int result = LIBC_NAMESPACE::strncmp(empty, s2, 3);31 // This should be '\0' - 'a' = -9732 ASSERT_EQ(result, -97);33 34 // Similar case if empty string is second argument.35 const char *s3 = "123";36 result = LIBC_NAMESPACE::strncmp(s3, empty, 3);37 // This should be '1' - '\0' = 4938 ASSERT_EQ(result, 49);39}40 41TEST(LlvmLibcStrNCmpTest, EqualStringsShouldReturnZeroWithSufficientLength) {42 const char *s1 = "abc";43 const char *s2 = "abc";44 int result = LIBC_NAMESPACE::strncmp(s1, s2, 3);45 ASSERT_EQ(result, 0);46 47 // Verify operands reversed.48 result = LIBC_NAMESPACE::strncmp(s2, s1, 3);49 ASSERT_EQ(result, 0);50}51 52TEST(LlvmLibcStrNCmpTest,53 ShouldReturnResultOfFirstDifferenceWithSufficientLength) {54 const char *s1 = "___B42__";55 const char *s2 = "___C55__";56 int result = LIBC_NAMESPACE::strncmp(s1, s2, 8);57 // This should return 'B' - 'C' = -1.58 ASSERT_EQ(result, -1);59 60 // Verify operands reversed.61 result = LIBC_NAMESPACE::strncmp(s2, s1, 8);62 // This should return 'C' - 'B' = 1.63 ASSERT_EQ(result, 1);64}65 66TEST(LlvmLibcStrNCmpTest,67 CapitalizedLetterShouldNotBeEqualWithSufficientLength) {68 const char *s1 = "abcd";69 const char *s2 = "abCd";70 int result = LIBC_NAMESPACE::strncmp(s1, s2, 4);71 // 'c' - 'C' = 32.72 ASSERT_EQ(result, 32);73 74 // Verify operands reversed.75 result = LIBC_NAMESPACE::strncmp(s2, s1, 4);76 // 'C' - 'c' = -32.77 ASSERT_EQ(result, -32);78}79 80TEST(LlvmLibcStrNCmpTest,81 UnequalLengthStringsShouldNotReturnZeroWithSufficientLength) {82 const char *s1 = "abc";83 const char *s2 = "abcd";84 int result = LIBC_NAMESPACE::strncmp(s1, s2, 4);85 // '\0' - 'd' = -100.86 ASSERT_EQ(result, -100);87 88 // Verify operands reversed.89 result = LIBC_NAMESPACE::strncmp(s2, s1, 4);90 // 'd' - '\0' = 100.91 ASSERT_EQ(result, 100);92}93 94TEST(LlvmLibcStrNCmpTest, StringArgumentSwapChangesSignWithSufficientLength) {95 const char *a = "a";96 const char *b = "b";97 int result = LIBC_NAMESPACE::strncmp(b, a, 1);98 // 'b' - 'a' = 1.99 ASSERT_EQ(result, 1);100 101 result = LIBC_NAMESPACE::strncmp(a, b, 1);102 // 'a' - 'b' = -1.103 ASSERT_EQ(result, -1);104}105 106// This group is actually testing strncmp functionality107 108TEST(LlvmLibcStrNCmpTest, NonEqualStringsEqualWithLengthZero) {109 const char *s1 = "abc";110 const char *s2 = "def";111 int result = LIBC_NAMESPACE::strncmp(s1, s2, 0);112 ASSERT_EQ(result, 0);113 114 // Verify operands reversed.115 result = LIBC_NAMESPACE::strncmp(s2, s1, 0);116 ASSERT_EQ(result, 0);117}118 119TEST(LlvmLibcStrNCmpTest, NonEqualStringsNotEqualWithLengthOne) {120 const char *s1 = "abc";121 const char *s2 = "def";122 int result = LIBC_NAMESPACE::strncmp(s1, s2, 1);123 ASSERT_EQ(result, -3);124 125 // Verify operands reversed.126 result = LIBC_NAMESPACE::strncmp(s2, s1, 1);127 ASSERT_EQ(result, 3);128}129 130TEST(LlvmLibcStrNCmpTest, NonEqualStringsEqualWithShorterLength) {131 const char *s1 = "___B42__";132 const char *s2 = "___C55__";133 int result = LIBC_NAMESPACE::strncmp(s1, s2, 3);134 ASSERT_EQ(result, 0);135 136 // This should return 'B' - 'C' = -1.137 result = LIBC_NAMESPACE::strncmp(s1, s2, 4);138 ASSERT_EQ(result, -1);139 140 // Verify operands reversed.141 result = LIBC_NAMESPACE::strncmp(s2, s1, 3);142 ASSERT_EQ(result, 0);143 144 // This should return 'C' - 'B' = 1.145 result = LIBC_NAMESPACE::strncmp(s2, s1, 4);146 ASSERT_EQ(result, 1);147}148 149TEST(LlvmLibcStrNCmpTest, StringComparisonEndsOnNullByteEvenWithLongerLength) {150 const char *s1 = "abc\0def";151 const char *s2 = "abc\0abc";152 int result = LIBC_NAMESPACE::strncmp(s1, s2, 7);153 ASSERT_EQ(result, 0);154 155 // Verify operands reversed.156 result = LIBC_NAMESPACE::strncmp(s2, s1, 7);157 ASSERT_EQ(result, 0);158}159 160TEST(LlvmLibcStrNCmpTest, Case) {161 const char *s1 = "aB";162 const char *s2 = "ab";163 int result = LIBC_NAMESPACE::strncmp(s1, s2, 2);164 ASSERT_LT(result, 0);165 166 // Verify operands reversed.167 result = LIBC_NAMESPACE::strncmp(s2, s1, 2);168 ASSERT_GT(result, 0);169}170