ladybird/AK/Tests/TestMemMem.cpp
AnotherTest 036b39cdfd AK: Implement memmem() for iterator haystacks
This uses the KMP algorithm to implement the search.
Also replaces the slow route of the normal memmem() with KMP, which
should be fairly faster (O(n + m) as opposed to O(n * m)) :^)
2020-12-08 23:34:38 +01:00

90 lines
3.8 KiB
C++

/*
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#include <AK/TestSuite.h>
#include <AK/MemMem.h>
TEST_CASE(bitap)
{
Array<u8, 8> haystack { 1, 0, 1, 2, 3, 4, 5, 0 };
Array<u8, 4> needle_0 { 2, 3, 4, 5 };
Array<u8, 4> needle_1 { 1, 2, 3, 4 };
Array<u8, 4> needle_2 { 3, 4, 5, 0 };
Array<u8, 4> needle_3 { 3, 4, 5, 6 };
auto result_0 = AK::memmem(haystack.data(), haystack.size(), needle_0.data(), needle_0.size());
auto result_1 = AK::memmem(haystack.data(), haystack.size(), needle_1.data(), needle_1.size());
auto result_2 = AK::memmem(haystack.data(), haystack.size(), needle_2.data(), needle_2.size());
auto result_3 = AK::memmem(haystack.data(), haystack.size(), needle_3.data(), needle_3.size());
EXPECT_EQ(result_0, &haystack[3]);
EXPECT_EQ(result_1, &haystack[2]);
EXPECT_EQ(result_2, &haystack[4]);
EXPECT_EQ(result_3, nullptr);
}
TEST_CASE(kmp_one_chunk)
{
Array<u8, 8> haystack { 1, 0, 1, 2, 3, 4, 5, 0 };
Array<Array<u8, 8>, 1> haystack_arr { haystack };
Array<u8, 4> needle_0 { 2, 3, 4, 5 };
Array<u8, 4> needle_1 { 1, 2, 3, 4 };
Array<u8, 4> needle_2 { 3, 4, 5, 0 };
Array<u8, 4> needle_3 { 3, 4, 5, 6 };
auto result_0 = AK::memmem(haystack_arr.begin(), haystack_arr.end(), needle_0);
auto result_1 = AK::memmem(haystack_arr.begin(), haystack_arr.end(), needle_1);
auto result_2 = AK::memmem(haystack_arr.begin(), haystack_arr.end(), needle_2);
auto result_3 = AK::memmem(haystack_arr.begin(), haystack_arr.end(), needle_3);
EXPECT_EQ(result_0.value_or(9), 3u);
EXPECT_EQ(result_1.value_or(9), 2u);
EXPECT_EQ(result_2.value_or(9), 4u);
EXPECT(!result_3.has_value());
}
TEST_CASE(kmp_two_chunks)
{
Array<u8, 4> haystack_first_half { 1, 0, 1, 2 }, haystack_second_half { 3, 4, 5, 0 };
Array<Array<u8, 4>, 2> haystack { haystack_first_half, haystack_second_half };
Array<u8, 4> needle_0 { 2, 3, 4, 5 };
Array<u8, 4> needle_1 { 1, 2, 3, 4 };
Array<u8, 4> needle_2 { 3, 4, 5, 0 };
Array<u8, 4> needle_3 { 3, 4, 5, 6 };
auto result_0 = AK::memmem(haystack.begin(), haystack.end(), needle_0);
auto result_1 = AK::memmem(haystack.begin(), haystack.end(), needle_1);
auto result_2 = AK::memmem(haystack.begin(), haystack.end(), needle_2);
auto result_3 = AK::memmem(haystack.begin(), haystack.end(), needle_3);
EXPECT_EQ(result_0.value_or(9), 3u);
EXPECT_EQ(result_1.value_or(9), 2u);
EXPECT_EQ(result_2.value_or(9), 4u);
EXPECT(!result_3.has_value());
}
TEST_MAIN(MemMem)