Tools/TestWebKitAPI/Tests/WTF/CStringView.cpp

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#include "config.h"
#include <wtf/text/CStringView.h>

#include <wtf/text/ASCIILiteral.h>
#include <wtf/text/WTFString.h>

namespace TestWebKitAPI {

TEST(WTF, CStringViewNullAndEmpty)
{
    CStringView string;
    EXPECT_TRUE(string.isNull());
    EXPECT_TRUE(string.isEmpty());
    EXPECT_EQ(string.utf8(), nullptr);
    EXPECT_TRUE(!string);
    EXPECT_FALSE(string);

    string = CStringView(nullptr);
    EXPECT_TRUE(string.isNull());
    EXPECT_TRUE(string.isEmpty());
    EXPECT_EQ(string.utf8(), nullptr);
    EXPECT_TRUE(!string);
    EXPECT_FALSE(string);

    string = CStringView(""_s);
    EXPECT_FALSE(string.isNull());
    EXPECT_TRUE(string.isEmpty());
    EXPECT_TRUE(string.utf8());
    EXPECT_TRUE(!string);
    EXPECT_FALSE(string);

    string = CStringView("test"_s);
    EXPECT_FALSE(string.isNull());
    EXPECT_FALSE(string.isEmpty());
    EXPECT_TRUE(string.utf8());
    EXPECT_FALSE(!string);
    EXPECT_TRUE(string);
}

TEST(WTF, CStringViewSize)
{
    CStringView string;
    EXPECT_EQ(string.lengthInBytes(), 0UZ);
    EXPECT_EQ(string.span().size(), 0UZ);
    EXPECT_EQ(string.spanIncludingNullTerminator().size(), 0UZ);

    string = CStringView(""_s);
    EXPECT_EQ(string.lengthInBytes(), 0UZ);
    EXPECT_EQ(string.span().size(), 0UZ);
    EXPECT_EQ(string.spanIncludingNullTerminator().size(), 1UZ);

    string = CStringView("test"_s);
    EXPECT_EQ(string.lengthInBytes(), 4UZ);
    EXPECT_EQ(string.span().size(), 4UZ);
    EXPECT_EQ(string.spanIncludingNullTerminator().size(), 5UZ);

    string = CStringView::unsafeFromUTF8("water🍉melon");
    EXPECT_EQ(string.lengthInBytes(), 14UZ);
    EXPECT_EQ(string.span().size(), 14UZ);
    EXPECT_EQ(string.spanIncludingNullTerminator().size(), 15UZ);
}

TEST(WTF, CStringViewFrom)
{
    const char* stringPtr = "test";
    CStringView string = CStringView::unsafeFromUTF8(stringPtr);
    EXPECT_EQ(string.lengthInBytes(), 4UZ);
    EXPECT_TRUE(string);
    EXPECT_EQ(string.utf8(), stringPtr);
    string = CStringView::fromUTF8(byteCast<char8_t>(unsafeSpanIncludingNullTerminator(stringPtr)));
    EXPECT_EQ(string.lengthInBytes(), 4UZ);
    EXPECT_TRUE(string);
    EXPECT_EQ(string.utf8(), stringPtr);

    stringPtr = nullptr;
    string = CStringView::unsafeFromUTF8(stringPtr);
    EXPECT_EQ(string.lengthInBytes(), 0UZ);
    EXPECT_FALSE(string);
    EXPECT_EQ(string.utf8(), stringPtr);
    string = CStringView::fromUTF8(byteCast<char8_t>(unsafeSpanIncludingNullTerminator(stringPtr)));
    EXPECT_EQ(string.lengthInBytes(), 0UZ);
    EXPECT_FALSE(string);
    EXPECT_EQ(string.utf8(), stringPtr);

    stringPtr = "";
    string = CStringView::unsafeFromUTF8(stringPtr);
    EXPECT_EQ(string.lengthInBytes(), 0UZ);
    EXPECT_FALSE(string.isNull());
    EXPECT_FALSE(string);
    EXPECT_EQ(string.utf8(), stringPtr);
    string = CStringView::fromUTF8(byteCast<char8_t>(unsafeSpanIncludingNullTerminator(stringPtr)));
    EXPECT_EQ(string.lengthInBytes(), 0UZ);
    EXPECT_FALSE(string.isNull());
    EXPECT_FALSE(string);
    EXPECT_EQ(string.utf8(), stringPtr);

    stringPtr = "water🍉melon";
    string = CStringView::unsafeFromUTF8(stringPtr);
    EXPECT_EQ(string.lengthInBytes(), 14UZ);
    EXPECT_TRUE(string);
    EXPECT_EQ(string.utf8(), stringPtr);
    string = CStringView::fromUTF8(byteCast<char8_t>(unsafeSpanIncludingNullTerminator(stringPtr)));
    EXPECT_EQ(string.lengthInBytes(), 14UZ);
    EXPECT_TRUE(string);
    EXPECT_EQ(string.utf8(), stringPtr);
}

TEST(WTF, CStringViewEquality)
{
    CStringView string("Test"_s);
    CStringView sameString("Test"_s);
    CStringView anotherString("another test"_s);
    CStringView nullString;
    CStringView nullString2(nullptr);
    CStringView emptyLiteral(""_s);

    EXPECT_EQ(string, string);
    EXPECT_EQ(string, sameString);
    EXPECT_TRUE(string != anotherString);
    EXPECT_TRUE(string != nullString);

    // Null vs null.
    EXPECT_EQ(nullString, nullString2);

    // Null vs empty (both have zero lengthInBytes).
    EXPECT_EQ(nullString, emptyLiteral);

    // Empty from unsafeFromUTF8 vs null and vs empty literal.
    char* bareEmptyString = strdup("");
    char* bareEmptyString2 = strdup("");
    auto emptyFromUTF8 = CStringView::unsafeFromUTF8(bareEmptyString);
    auto emptyFromUTF8_2 = CStringView::unsafeFromUTF8(bareEmptyString2);
    EXPECT_EQ(emptyFromUTF8, emptyFromUTF8_2);
    EXPECT_EQ(emptyFromUTF8, nullString);
    EXPECT_EQ(emptyFromUTF8, emptyLiteral);
    free(bareEmptyString);
    free(bareEmptyString2);

    // CStringView vs ASCIILiteral.
    EXPECT_EQ(string, "Test"_s);
    EXPECT_EQ("Test"_s, string);
    EXPECT_TRUE(string != "Other"_s);
    EXPECT_EQ(nullString, ""_s);
    EXPECT_EQ(emptyLiteral, ""_s);
}

} // namespace TestWebKitAPI