Tools/TestWebKitAPI/Tests/WTF/cf/StringCF.cpp

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#include "config.h"

#include "Helpers/Test.h"
#include <CoreFoundation/CoreFoundation.h>
#include <wtf/RetainPtr.h>
#include <wtf/Vector.h>
#include <wtf/text/WTFString.h>

namespace TestWebKitAPI {

TEST(StringCF, ConstructFromNull)
{
    String string(static_cast<CFStringRef>(nullptr));
    EXPECT_TRUE(string.isNull());
}

TEST(StringCF, ConstructFromEmpty)
{
    String string(CFSTR(""));
    EXPECT_FALSE(string.isNull());
    EXPECT_TRUE(string.isEmpty());
    EXPECT_TRUE(string.is8Bit());
}

TEST(StringCF, ConstructFromLatin1)
{
    String string(CFSTR("Hello, world!"));
    EXPECT_EQ(string.length(), 13u);
    EXPECT_TRUE(string.is8Bit());
    EXPECT_EQ(string, "Hello, world!"_s);
}

TEST(StringCF, ConstructFromLatin1WithHighBytes)
{
    // Create a CFString with Latin-1 characters above ASCII range (e.g. U+00E9 = é).
    const uint8_t latin1Bytes[] = { 'r', 0xE9, 's', 'u', 'm', 0xE9 }; // "résumé" in Latin-1
    RetainPtr cfString = adoptCF(CFStringCreateWithBytes(kCFAllocatorDefault, latin1Bytes, sizeof(latin1Bytes), kCFStringEncodingISOLatin1, false));

    String string(cfString.get());
    EXPECT_EQ(string.length(), 6u);
    EXPECT_FALSE(string.isNull());
    EXPECT_EQ(string, String::fromUTF8("résumé"));
}

TEST(StringCF, ConstructFromUTF16WithLatin1Characters)
{
    // Create a long CFString from UTF-16 characters that are all in the Latin-1 range.
    // Use a long string so CF is likely to expose its internal UTF-16 buffer via
    // CFStringGetCharactersSpan, exercising the create8BitIfPossible narrowing path.
    Vector<char16_t> characters(FillWith { }, 4096, 'A');
    RetainPtr cfString = adoptCF(CFStringCreateWithCharacters(kCFAllocatorDefault, reinterpret_cast<const UniChar*>(characters.span().data()), characters.size()));

    String string(cfString.get());
    EXPECT_EQ(string.length(), 4096u);
    EXPECT_TRUE(string.is8Bit());
    EXPECT_EQ(string, String(Vector<Latin1Character>(FillWith { }, 4096, 'A')));
}

TEST(StringCF, ConstructFromUTF16WithHighLatin1Characters)
{
    // Create a CFString from UTF-16 characters that include high Latin-1 chars (U+00E9).
    const char16_t characters[] = { 'r', 0x00E9, 's', 'u', 'm', 0x00E9 }; // "résumé"
    RetainPtr cfString = adoptCF(CFStringCreateWithCharacters(kCFAllocatorDefault, reinterpret_cast<const UniChar*>(characters), std::size(characters)));

    String string(cfString.get());
    EXPECT_EQ(string.length(), 6u);
    EXPECT_FALSE(string.isNull());
    EXPECT_EQ(string, String::fromUTF8("résumé"));
}

TEST(StringCF, ConstructFromUTF16WithNonLatin1Characters)
{
    // Create a CFString with characters outside Latin-1 range (e.g. U+4E16 = 世, U+754C = 界).
    const char16_t characters[] = { 0x4E16, 0x754C }; // "世界"
    RetainPtr cfString = adoptCF(CFStringCreateWithCharacters(kCFAllocatorDefault, reinterpret_cast<const UniChar*>(characters), std::size(characters)));

    String string(cfString.get());
    EXPECT_EQ(string.length(), 2u);
    EXPECT_FALSE(string.is8Bit());
    EXPECT_EQ(string[0], 0x4E16);
    EXPECT_EQ(string[1], 0x754C);
}

TEST(StringCF, ConstructFromUTF16MixedLatin1AndNonLatin1)
{
    // Mix of Latin-1 and non-Latin-1 characters — should stay 16-bit.
    const char16_t characters[] = { 'H', 'i', 0x4E16 }; // "Hi世"
    RetainPtr cfString = adoptCF(CFStringCreateWithCharacters(kCFAllocatorDefault, reinterpret_cast<const UniChar*>(characters), std::size(characters)));

    String string(cfString.get());
    EXPECT_EQ(string.length(), 3u);
    EXPECT_FALSE(string.is8Bit());
    EXPECT_EQ(string[0], 'H');
    EXPECT_EQ(string[1], 'i');
    EXPECT_EQ(string[2], 0x4E16);
}

TEST(StringCF, RoundTrip)
{
    String original("WebKit"_s);
    auto cfString = original.createCFString();
    String roundTripped(cfString.get());
    EXPECT_EQ(original, roundTripped);
    EXPECT_TRUE(roundTripped.is8Bit());
}

} // namespace TestWebKitAPI