ladybird/Tests/LibC/TestWchar.cpp

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/*
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* Copyright (c) 2021-2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibTest/TestCase.h>
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#include <errno.h>
#include <limits.h>
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#include <string.h>
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#include <time.h>
#include <wchar.h>
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TEST_CASE(wcspbrk)
{
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wchar_t const* input;
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wchar_t* ret;
// Test empty haystack.
ret = wcspbrk(L"", L"ab");
EXPECT_EQ(ret, nullptr);
// Test empty needle.
ret = wcspbrk(L"ab", L"");
EXPECT_EQ(ret, nullptr);
// Test search for a single character.
input = L"abcd";
ret = wcspbrk(input, L"a");
EXPECT_EQ(ret, input);
// Test search for multiple characters, none matches.
ret = wcspbrk(input, L"zxy");
EXPECT_EQ(ret, nullptr);
// Test search for multiple characters, last matches.
ret = wcspbrk(input, L"zxyc");
EXPECT_EQ(ret, input + 2);
}
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TEST_CASE(wcsstr)
{
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wchar_t const* input = L"abcde";
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wchar_t* ret;
// Empty needle should return haystack.
ret = wcsstr(input, L"");
EXPECT_EQ(ret, input);
// Test exact match.
ret = wcsstr(input, input);
EXPECT_EQ(ret, input);
// Test match at string start.
ret = wcsstr(input, L"ab");
EXPECT_EQ(ret, input);
// Test match at string end.
ret = wcsstr(input, L"de");
EXPECT_EQ(ret, input + 3);
// Test no match.
ret = wcsstr(input, L"z");
EXPECT_EQ(ret, nullptr);
// Test needle that is longer than the haystack.
ret = wcsstr(input, L"abcdef");
EXPECT_EQ(ret, nullptr);
}
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TEST_CASE(wmemchr)
{
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wchar_t const* input = L"abcde";
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wchar_t* ret;
// Empty haystack returns nothing.
ret = wmemchr(L"", L'c', 0);
EXPECT_EQ(ret, nullptr);
// Not included character returns nothing.
ret = wmemchr(input, L'z', 5);
EXPECT_EQ(ret, nullptr);
// Match at string start.
ret = wmemchr(input, L'a', 5);
EXPECT_EQ(ret, input);
// Match at string end.
ret = wmemchr(input, L'e', 5);
EXPECT_EQ(ret, input + 4);
input = L"abcde\0fg";
// Handle finding null characters.
ret = wmemchr(input, L'\0', 8);
EXPECT_EQ(ret, input + 5);
// Don't stop at null characters.
ret = wmemchr(input, L'f', 8);
EXPECT_EQ(ret, input + 6);
}
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TEST_CASE(wmemcpy)
{
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wchar_t const* input = L"abc\0def";
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auto buf = static_cast<wchar_t*>(malloc(8 * sizeof(wchar_t)));
if (!buf) {
FAIL("Could not allocate space for copy target");
return;
}
wchar_t* ret = wmemcpy(buf, input, 8);
EXPECT_EQ(ret, buf);
EXPECT_EQ(memcmp(buf, input, 8 * sizeof(wchar_t)), 0);
}
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TEST_CASE(wmemset)
{
auto buf_length = 8;
auto buf = static_cast<wchar_t*>(calloc(buf_length, sizeof(wchar_t)));
if (!buf) {
FAIL("Could not allocate memory for target buffer");
return;
}
wchar_t* ret = wmemset(buf, L'\U0001f41e', buf_length - 1);
EXPECT_EQ(ret, buf);
for (int i = 0; i < buf_length - 1; i++) {
EXPECT_EQ(buf[i], L'\U0001f41e');
}
EXPECT_EQ(buf[buf_length - 1], L'\0');
free(buf);
}
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TEST_CASE(wmemmove)
{
wchar_t* ret;
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wchar_t const* string = L"abc\0def";
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auto buf = static_cast<wchar_t*>(calloc(32, sizeof(wchar_t)));
if (!buf) {
FAIL("Could not allocate memory for target buffer");
return;
}
// Test moving to smaller addresses.
wmemcpy(buf + 3, string, 8);
ret = wmemmove(buf + 1, buf + 3, 8);
EXPECT_EQ(ret, buf + 1);
EXPECT_EQ(memcmp(string, buf + 1, 8 * sizeof(wchar_t)), 0);
// Test moving to larger addresses.
wmemcpy(buf + 16, string, 8);
ret = wmemmove(buf + 18, buf + 16, 8);
EXPECT_EQ(ret, buf + 18);
EXPECT_EQ(memcmp(string, buf + 18, 8 * sizeof(wchar_t)), 0);
free(buf);
}
TEST_CASE(wcscoll)
{
// Check if wcscoll is sorting correctly. At the moment we are doing raw char comparisons,
// so it's digits, then uppercase letters, then lowercase letters.
// Equalness between equal strings.
EXPECT(wcscoll(L"", L"") == 0);
EXPECT(wcscoll(L"0", L"0") == 0);
// Shorter strings before longer strings.
EXPECT(wcscoll(L"", L"0") < 0);
EXPECT(wcscoll(L"0", L"") > 0);
EXPECT(wcscoll(L"123", L"1234") < 0);
EXPECT(wcscoll(L"1234", L"123") > 0);
// Order within digits.
EXPECT(wcscoll(L"0", L"9") < 0);
EXPECT(wcscoll(L"9", L"0") > 0);
// Digits before uppercase letters.
EXPECT(wcscoll(L"9", L"A") < 0);
EXPECT(wcscoll(L"A", L"9") > 0);
// Order within uppercase letters.
EXPECT(wcscoll(L"A", L"Z") < 0);
EXPECT(wcscoll(L"Z", L"A") > 0);
// Uppercase letters before lowercase letters.
EXPECT(wcscoll(L"Z", L"a") < 0);
EXPECT(wcscoll(L"a", L"Z") > 0);
// Uppercase letters before lowercase letters.
EXPECT(wcscoll(L"a", L"z") < 0);
EXPECT(wcscoll(L"z", L"a") > 0);
}
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TEST_CASE(mbsinit)
{
// Ensure that nullptr is considered an initial state.
EXPECT(mbsinit(nullptr) != 0);
// Ensure that a zero-initialized state is recognized as initial state.
mbstate_t state = {};
EXPECT(mbsinit(&state) != 0);
// Read a partial multibyte sequence (0b11011111 / 0xdf).
size_t ret = mbrtowc(nullptr, "\xdf", 1, &state);
if (ret != -2ul)
FAIL(DeprecatedString::formatted("mbrtowc accepted partial multibyte sequence with return code {} (expected -2)", static_cast<ssize_t>(ret)));
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// Ensure that we are not in an initial state.
EXPECT(mbsinit(&state) == 0);
// Read the remaining multibyte sequence (0b10111111 / 0xbf).
ret = mbrtowc(nullptr, "\xbf", 1, &state);
if (ret != 1ul)
FAIL(DeprecatedString::formatted("mbrtowc did not consume the expected number of bytes (1), returned {} instead", static_cast<ssize_t>(ret)));
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// Ensure that we are in an initial state again.
EXPECT(mbsinit(&state) != 0);
}
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TEST_CASE(mbrtowc)
{
size_t ret = 0;
mbstate_t state = {};
wchar_t wc = 0;
// Ensure that we can parse normal ASCII characters.
ret = mbrtowc(&wc, "Hello", 5, &state);
EXPECT_EQ(ret, 1ul);
EXPECT_EQ(wc, static_cast<wchar_t>('H'));
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// Try two three-byte codepoints (™™), only one of which should be consumed.
ret = mbrtowc(&wc, "\xe2\x84\xa2\xe2\x84\xa2", 6, &state);
EXPECT_EQ(ret, 3ul);
EXPECT_EQ(wc, static_cast<wchar_t>(0x2122));
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// Try a null character, which should return 0 and reset the state to the initial state.
ret = mbrtowc(&wc, "\x00\x00", 2, &state);
EXPECT_EQ(ret, 0ul);
EXPECT_EQ(wc, static_cast<wchar_t>(0));
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EXPECT_NE(mbsinit(&state), 0);
// Try an incomplete multibyte character.
ret = mbrtowc(&wc, "\xe2\x84", 2, &state);
EXPECT_EQ(ret, -2ul);
EXPECT_EQ(mbsinit(&state), 0);
mbstate_t incomplete_state = state;
// Finish the previous multibyte character.
ret = mbrtowc(&wc, "\xa2", 1, &state);
EXPECT_EQ(ret, 1ul);
EXPECT_EQ(wc, static_cast<wchar_t>(0x2122));
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// Try an invalid multibyte sequence.
// Reset the state afterwards because the effects are undefined.
ret = mbrtowc(&wc, "\xff", 1, &state);
EXPECT_EQ(ret, -1ul);
EXPECT_EQ(errno, EILSEQ);
state = {};
// Try a successful conversion, but without target address.
ret = mbrtowc(nullptr, "\xe2\x84\xa2\xe2\x84\xa2", 6, &state);
EXPECT_EQ(ret, 3ul);
// Test the "null byte shorthand". Ensure that wc is ignored.
state = {};
wchar_t old_wc = wc;
ret = mbrtowc(&wc, nullptr, 0, &state);
EXPECT_EQ(ret, 0ul);
EXPECT_EQ(wc, old_wc);
// Test recognition of incomplete multibyte sequences.
ret = mbrtowc(nullptr, nullptr, 0, &incomplete_state);
EXPECT_EQ(ret, -1ul);
EXPECT_EQ(errno, EILSEQ);
}
TEST_CASE(wcrtomb)
{
char buf[MB_LEN_MAX];
size_t ret = 0;
// Ensure that `wc` is ignored when buf is a nullptr.
ret = wcrtomb(nullptr, L'a', nullptr);
EXPECT_EQ(ret, 1ul);
ret = wcrtomb(nullptr, L'\U0001F41E', nullptr);
EXPECT_EQ(ret, 1ul);
// When the buffer is non-null, the multibyte representation is written into it.
ret = wcrtomb(buf, L'a', nullptr);
EXPECT_EQ(ret, 1ul);
EXPECT_EQ(memcmp(buf, "a", ret), 0);
ret = wcrtomb(buf, L'\U0001F41E', nullptr);
EXPECT_EQ(ret, 4ul);
EXPECT_EQ(memcmp(buf, "\xf0\x9f\x90\x9e", ret), 0);
// When the wide character is invalid, -1 is returned and errno is set to EILSEQ.
ret = wcrtomb(buf, 0x110000, nullptr);
EXPECT_EQ(ret, (size_t)-1);
EXPECT_EQ(errno, EILSEQ);
// Replacement characters and conversion errors are not confused.
ret = wcrtomb(buf, L'\uFFFD', nullptr);
EXPECT_NE(ret, (size_t)-1);
}
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TEST_CASE(wcsrtombs)
{
mbstate_t state = {};
char buf[MB_LEN_MAX * 4];
const wchar_t good_chars[] = { L'\U0001F41E', L'\U0001F41E', L'\0' };
const wchar_t bad_chars[] = { L'\U0001F41E', static_cast<wchar_t>(0x1111F41E), L'\0' };
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wchar_t const* src;
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size_t ret = 0;
// Convert normal and valid wchar_t values.
src = good_chars;
ret = wcsrtombs(buf, &src, 9, &state);
EXPECT_EQ(ret, 8ul);
EXPECT_EQ(memcmp(buf, "\xf0\x9f\x90\x9e\xf0\x9f\x90\x9e", 9), 0);
EXPECT_EQ(src, nullptr);
EXPECT_NE(mbsinit(&state), 0);
// Stop on invalid wchar values.
src = bad_chars;
ret = wcsrtombs(buf, &src, 9, &state);
EXPECT_EQ(ret, -1ul);
EXPECT_EQ(memcmp(buf, "\xf0\x9f\x90\x9e", 4), 0);
EXPECT_EQ(errno, EILSEQ);
EXPECT_EQ(src, bad_chars + 1);
// Valid characters but not enough space.
src = good_chars;
ret = wcsrtombs(buf, &src, 7, &state);
EXPECT_EQ(ret, 4ul);
EXPECT_EQ(memcmp(buf, "\xf0\x9f\x90\x9e", 4), 0);
EXPECT_EQ(src, good_chars + 1);
// Try a conversion with no destination and too short length.
src = good_chars;
ret = wcsrtombs(nullptr, &src, 2, &state);
EXPECT_EQ(ret, 8ul);
EXPECT_EQ(src, nullptr);
EXPECT_NE(mbsinit(&state), 0);
// Try a conversion using the internal anonymous state.
src = good_chars;
ret = wcsrtombs(buf, &src, 9, nullptr);
EXPECT_EQ(ret, 8ul);
EXPECT_EQ(memcmp(buf, "\xf0\x9f\x90\x9e\xf0\x9f\x90\x9e", 9), 0);
EXPECT_EQ(src, nullptr);
}
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TEST_CASE(wcsnrtombs)
{
mbstate_t state = {};
const wchar_t good_chars[] = { L'\U0001F41E', L'\U0001F41E', L'\0' };
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wchar_t const* src;
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size_t ret = 0;
// Convert nothing.
src = good_chars;
ret = wcsnrtombs(nullptr, &src, 0, 0, &state);
EXPECT_EQ(ret, 0ul);
EXPECT_EQ(src, good_chars);
// Convert one wide char.
src = good_chars;
ret = wcsnrtombs(nullptr, &src, 1, 0, &state);
EXPECT_EQ(ret, 4ul);
EXPECT_EQ(src, good_chars + 1);
// Encounter a null character.
src = good_chars;
ret = wcsnrtombs(nullptr, &src, 4, 0, &state);
EXPECT_EQ(ret, 8ul);
EXPECT_EQ(src, nullptr);
}
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TEST_CASE(mbsrtowcs)
{
mbstate_t state = {};
wchar_t buf[4];
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char const good_chars[] = "\xf0\x9f\x90\x9e\xf0\x9f\x90\x9e";
char const bad_chars[] = "\xf0\x9f\x90\x9e\xf0\xff\x90\x9e";
char const* src;
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size_t ret = 0;
// Convert normal and valid multibyte sequences.
src = good_chars;
ret = mbsrtowcs(buf, &src, 3, &state);
EXPECT_EQ(ret, 2ul);
EXPECT_EQ(buf[0], L'\U0001F41E');
EXPECT_EQ(buf[1], L'\U0001F41E');
EXPECT_EQ(buf[2], L'\0');
EXPECT_EQ(src, nullptr);
EXPECT_NE(mbsinit(&state), 0);
// Stop on invalid multibyte sequences.
src = bad_chars;
ret = mbsrtowcs(buf, &src, 3, &state);
EXPECT_EQ(ret, -1ul);
EXPECT_EQ(buf[0], L'\U0001F41E');
EXPECT_EQ(errno, EILSEQ);
EXPECT_EQ(src, bad_chars + 4);
// Valid sequence but not enough space.
src = good_chars;
ret = mbsrtowcs(buf, &src, 1, &state);
EXPECT_EQ(ret, 1ul);
EXPECT_EQ(buf[0], L'\U0001F41E');
EXPECT_EQ(src, good_chars + 4);
// Try a conversion with no destination and too short length.
src = good_chars;
ret = mbsrtowcs(nullptr, &src, 1, &state);
EXPECT_EQ(ret, 2ul);
EXPECT_EQ(src, nullptr);
EXPECT_NE(mbsinit(&state), 0);
// Try a conversion using the internal anonymous state.
src = good_chars;
ret = mbsrtowcs(buf, &src, 3, nullptr);
EXPECT_EQ(ret, 2ul);
EXPECT_EQ(buf[0], L'\U0001F41E');
EXPECT_EQ(buf[1], L'\U0001F41E');
EXPECT_EQ(buf[2], L'\0');
EXPECT_EQ(src, nullptr);
}
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TEST_CASE(mbsnrtowcs)
{
mbstate_t state = {};
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char const good_chars[] = "\xf0\x9f\x90\x9e\xf0\x9f\x90\x9e";
char const* src;
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size_t ret = 0;
// Convert nothing.
src = good_chars;
ret = mbsnrtowcs(nullptr, &src, 0, 0, &state);
EXPECT_EQ(ret, 0ul);
EXPECT_EQ(src, good_chars);
// Convert one full wide character.
src = good_chars;
ret = mbsnrtowcs(nullptr, &src, 4, 0, &state);
EXPECT_EQ(ret, 1ul);
EXPECT_EQ(src, good_chars + 4);
// Encounter a null character.
src = good_chars;
ret = mbsnrtowcs(nullptr, &src, 10, 0, &state);
EXPECT_EQ(ret, 2ul);
EXPECT_EQ(src, nullptr);
// Convert an incomplete character.
// Make sure that we point past the last processed byte.
src = good_chars;
ret = mbsnrtowcs(nullptr, &src, 6, 0, &state);
EXPECT_EQ(ret, 1ul);
EXPECT_EQ(src, good_chars + 6);
EXPECT_EQ(mbsinit(&state), 0);
// Finish converting the incomplete character.
ret = mbsnrtowcs(nullptr, &src, 2, 0, &state);
EXPECT_EQ(ret, 1ul);
EXPECT_EQ(src, good_chars + 8);
}
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TEST_CASE(wcslcpy)
{
auto buf = static_cast<wchar_t*>(malloc(8 * sizeof(wchar_t)));
if (!buf) {
FAIL("Could not allocate space for copy target");
return;
}
size_t ret;
// If buffer is long enough, a straight-forward string copy is performed.
ret = wcslcpy(buf, L"abc", 8);
EXPECT_EQ(ret, 3ul);
EXPECT_EQ(wmemcmp(L"abc", buf, 4), 0);
// If buffer is (supposedly) too small, the string will be truncated.
ret = wcslcpy(buf, L"1234", 4);
EXPECT_EQ(ret, 4ul);
EXPECT_EQ(wmemcmp(L"123", buf, 4), 0);
// If the buffer is null, the length of the input is returned.
ret = wcslcpy(nullptr, L"abc", 0);
EXPECT_EQ(ret, 3ul);
}
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TEST_CASE(mbrlen)
{
size_t ret = 0;
mbstate_t state = {};
// Ensure that we can parse normal ASCII characters.
ret = mbrlen("Hello", 5, &state);
EXPECT_EQ(ret, 1ul);
// Try two three-byte codepoints (™™), only one of which should be consumed.
ret = mbrlen("\xe2\x84\xa2\xe2\x84\xa2", 6, &state);
EXPECT_EQ(ret, 3ul);
// Try a null character, which should return 0 and reset the state to the initial state.
ret = mbrlen("\x00\x00", 2, &state);
EXPECT_EQ(ret, 0ul);
EXPECT_NE(mbsinit(&state), 0);
// Try an incomplete multibyte character.
ret = mbrlen("\xe2\x84", 2, &state);
EXPECT_EQ(ret, -2ul);
EXPECT_EQ(mbsinit(&state), 0);
// Finish the previous multibyte character.
ret = mbrlen("\xa2", 1, &state);
EXPECT_EQ(ret, 1ul);
// Try an invalid multibyte sequence.
// Reset the state afterwards because the effects are undefined.
ret = mbrlen("\xff", 1, &state);
EXPECT_EQ(ret, -1ul);
EXPECT_EQ(errno, EILSEQ);
state = {};
}
TEST_CASE(mbtowc)
{
int ret = 0;
wchar_t wc = 0;
// Ensure that we can parse normal ASCII characters.
ret = mbtowc(&wc, "Hello", 5);
EXPECT_EQ(ret, 1);
EXPECT_EQ(wc, static_cast<wchar_t>('H'));
// Try two three-byte codepoints (™™), only one of which should be consumed.
ret = mbtowc(&wc, "\xe2\x84\xa2\xe2\x84\xa2", 6);
EXPECT_EQ(ret, 3);
EXPECT_EQ(wc, static_cast<wchar_t>(0x2122));
// Try a null character, which should return 0.
ret = mbtowc(&wc, "\x00\x00", 2);
EXPECT_EQ(ret, 0);
EXPECT_EQ(wc, static_cast<wchar_t>(0));
// Try an incomplete multibyte character.
ret = mbtowc(&wc, "\xe2\x84", 2);
EXPECT_EQ(ret, -1);
EXPECT_EQ(errno, EILSEQ);
// Ask if we support shift states and reset the internal state in the process.
ret = mbtowc(nullptr, nullptr, 2);
EXPECT_EQ(ret, 0); // We don't support shift states.
ret = mbtowc(nullptr, "\x00", 1);
EXPECT_EQ(ret, 0); // No error likely means that the state is working again.
// Try an invalid multibyte sequence.
ret = mbtowc(&wc, "\xff", 1);
EXPECT_EQ(ret, -1);
EXPECT_EQ(errno, EILSEQ);
// Try a successful conversion, but without target address.
ret = mbtowc(nullptr, "\xe2\x84\xa2\xe2\x84\xa2", 6);
EXPECT_EQ(ret, 3);
}
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TEST_CASE(mblen)
{
int ret = 0;
// Ensure that we can parse normal ASCII characters.
ret = mblen("Hello", 5);
EXPECT_EQ(ret, 1);
// Try two three-byte codepoints (™™), only one of which should be consumed.
ret = mblen("\xe2\x84\xa2\xe2\x84\xa2", 6);
EXPECT_EQ(ret, 3);
// Try a null character, which should return 0.
ret = mblen("\x00\x00", 2);
EXPECT_EQ(ret, 0);
// Try an incomplete multibyte character.
ret = mblen("\xe2\x84", 2);
EXPECT_EQ(ret, -1);
EXPECT_EQ(errno, EILSEQ);
// Ask if we support shift states and reset the internal state in the process.
ret = mblen(nullptr, 2);
EXPECT_EQ(ret, 0); // We don't support shift states.
ret = mblen("\x00", 1);
EXPECT_EQ(ret, 0); // No error likely means that the state is working again.
// Try an invalid multibyte sequence.
ret = mblen("\xff", 1);
EXPECT_EQ(ret, -1);
EXPECT_EQ(errno, EILSEQ);
}
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TEST_CASE(wcsftime)
{
// FIXME: Test actual wide char inputs once those are implemented.
auto* buf = static_cast<wchar_t*>(malloc(32 * sizeof(wchar_t)));
if (!buf) {
FAIL("Could not allocate space for copy target");
return;
}
struct tm time = {
.tm_sec = 54,
.tm_min = 44,
.tm_hour = 12,
.tm_mday = 27,
.tm_mon = 4,
.tm_year = 121,
.tm_wday = 4,
.tm_yday = 0,
.tm_isdst = 0,
};
size_t ret;
// Normal behavior.
ret = wcsftime(buf, 32, L"%a, %d %b %Y %H:%M:%S", &time);
EXPECT_EQ(ret, 25ul);
EXPECT_EQ(wcscmp(buf, L"Thu, 27 May 2021 12:44:54"), 0);
// String fits exactly.
ret = wcsftime(buf, 26, L"%a, %d %b %Y %H:%M:%S", &time);
EXPECT_EQ(ret, 25ul);
EXPECT_EQ(wcscmp(buf, L"Thu, 27 May 2021 12:44:54"), 0);
// Buffer is too small.
ret = wcsftime(buf, 25, L"%a, %d %b %Y %H:%M:%S", &time);
EXPECT_EQ(ret, 0ul);
ret = wcsftime(buf, 1, L"%a, %d %b %Y %H:%M:%S", &time);
EXPECT_EQ(ret, 0ul);
ret = wcsftime(nullptr, 0, L"%a, %d %b %Y %H:%M:%S", &time);
EXPECT_EQ(ret, 0ul);
}