Tools/TestWebKitAPI/Tests/WTF/LEBEncoder.cpp

/*
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#include "config.h"
#include <wtf/LEBEncoder.h>

#include <wtf/LEBDecoder.h>
#include <wtf/Vector.h>

namespace TestWebKitAPI {

static void testUInt32LEBEncode(uint32_t value, std::initializer_list<uint8_t> expected)
{
    Vector<uint8_t> bytes;
    WTF::LEBEncoder::encodeUInt32(bytes, value);
    EXPECT_EQ(Vector<uint8_t>(expected), bytes) << value;

    size_t offset = 0;
    EXPECT_EQ(value, WTF::LEBDecoder::decodeUInt32OrCrash(bytes, offset));
    EXPECT_EQ(bytes.size(), offset);
}

static void testInt32LEBEncode(int32_t value, std::initializer_list<uint8_t> expected)
{
    Vector<uint8_t> bytes;
    WTF::LEBEncoder::encodeInt32(bytes, value);
    EXPECT_EQ(Vector<uint8_t>(expected), bytes) << value;

    size_t offset = 0;
    EXPECT_EQ(value, WTF::LEBDecoder::decodeInt32OrCrash(bytes, offset));
    EXPECT_EQ(bytes.size(), offset);
}

TEST(WTF, LEBEncoderUInt32)
{
    testUInt32LEBEncode(0, { 0x00 });
    testUInt32LEBEncode(0x7f, { 0x7f });
    testUInt32LEBEncode(0x80, { 0x80, 0x01 });
    testUInt32LEBEncode(0x380, { 0x80, 0x07 });
    testUInt32LEBEncode(0x82f3, { 0xf3, 0x85, 0x02 });
    testUInt32LEBEncode(0xe9fc2f3, { 0xf3, 0x85, 0xff, 0x74 });
    testUInt32LEBEncode(0xffffffff, { 0xff, 0xff, 0xff, 0xff, 0x0f });
}

TEST(WTF, LEBEncoderInt32)
{
    testInt32LEBEncode(0, { 0x00 });
    testInt32LEBEncode(1, { 0x01 });
    testInt32LEBEncode(-1, { 0x7f });
    testInt32LEBEncode(63, { 0x3f });
    testInt32LEBEncode(64, { 0xc0, 0x00 });
    testInt32LEBEncode(-64, { 0x40 });
    testInt32LEBEncode(-65, { 0xbf, 0x7f });
    testInt32LEBEncode(-128, { 0x80, 0x7f });
    testInt32LEBEncode(8191, { 0xff, 0x3f });
    testInt32LEBEncode(-8192, { 0x80, 0x40 });
    testInt32LEBEncode(std::numeric_limits<int32_t>::max(), { 0xff, 0xff, 0xff, 0xff, 0x07 });
    testInt32LEBEncode(std::numeric_limits<int32_t>::min(), { 0x80, 0x80, 0x80, 0x80, 0x78 });
}

TEST(WTF, LEBEncoderRoundTrip64)
{
    for (uint64_t value : std::initializer_list<uint64_t> { 0, 0x7f, 0x80, 0xffffffff, 0x100000000, std::numeric_limits<uint64_t>::max() }) {
        Vector<uint8_t> bytes;
        WTF::LEBEncoder::encodeUInt64(bytes, value);
        size_t offset = 0;
        EXPECT_EQ(value, WTF::LEBDecoder::decodeUInt64OrCrash(bytes, offset));
        EXPECT_EQ(bytes.size(), offset);
    }
    for (int64_t value : std::initializer_list<int64_t> { 0, -1, 63, -64, 64, -65, 0x7fffffff, -0x80000000, std::numeric_limits<int64_t>::max(), std::numeric_limits<int64_t>::min() }) {
        Vector<uint8_t> bytes;
        WTF::LEBEncoder::encodeInt64(bytes, value);
        size_t offset = 0;
        EXPECT_EQ(value, WTF::LEBDecoder::decodeInt64OrCrash(bytes, offset));
        EXPECT_EQ(bytes.size(), offset);
    }
}

} // namespace TestWebKitAPI