intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 134 insertions, 0 deletions

diff --git a/library/cpp/yt/coding/unittests/varint_ut.cpp b/library/cpp/yt/coding/unittests/varint_ut.cpp
new file mode 100644
index 0000000000..ed83ab5c92
--- /dev/null
+++ b/library/cpp/yt/coding/unittests/varint_ut.cpp
@@ -0,0 +1,134 @@
+#include <library/cpp/testing/gtest/gtest.h>
+
+#include <library/cpp/yt/coding/varint.h>
+
+#include <util/random/random.h>
+
+#include <util/string/escape.h>
+
+#include <tuple>
+
+namespace NYT {
+namespace {
+
+using ::testing::Values;
+
+////////////////////////////////////////////////////////////////////////////////
+
+class TWriteVarIntTest: public ::testing::TestWithParam<std::tuple<ui64, TString> >
+{ };
+
+TEST_P(TWriteVarIntTest, Serialization)
+{
+    ui64 value = std::get<0>(GetParam());
+    TString rightAnswer = std::get<1>(GetParam());
+
+    TStringStream outputStream;
+    WriteVarUint64(&outputStream, value);
+    EXPECT_EQ(rightAnswer, outputStream.Str());
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+class TReadVarIntTest: public ::testing::TestWithParam<std::tuple<ui64, TString> >
+{ };
+
+TEST_P(TReadVarIntTest, Serialization)
+{
+    ui64 rightAnswer = std::get<0>(GetParam());
+    TString input = std::get<1>(GetParam());
+
+    TStringInput inputStream(input);
+    ui64 value;
+    ReadVarUint64(&inputStream, &value);
+    EXPECT_EQ(rightAnswer, value);
+}
+
+TEST(TReadVarIntTest, Overflow)
+{
+    TString input("\x80\x80\x80\x80\x80\x80\x80\x80\x80\x80\x01", 11);
+    TStringInput inputStream(input);
+    ui64 value;
+    EXPECT_ANY_THROW(ReadVarUint64(&inputStream, &value));
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+auto ValuesForVarIntTests = Values(
+    // Simple cases.
+    std::make_tuple(0x0ull,                TString("\x00", 1)),
+    std::make_tuple(0x1ull,                TString("\x01", 1)),
+    std::make_tuple(0x2ull,                TString("\x02", 1)),
+    std::make_tuple(0x3ull,                TString("\x03", 1)),
+    std::make_tuple(0x4ull,                TString("\x04", 1)),
+
+    // The following "magic numbers" are critical points for varint encoding.
+    std::make_tuple((1ull << 7) - 1,       TString("\x7f", 1)),
+    std::make_tuple((1ull << 7),           TString("\x80\x01", 2)),
+    std::make_tuple((1ull << 14) - 1,      TString("\xff\x7f", 2)),
+    std::make_tuple((1ull << 14),          TString("\x80\x80\x01", 3)),
+    std::make_tuple((1ull << 21) - 1,      TString("\xff\xff\x7f", 3)),
+    std::make_tuple((1ull << 21),          TString("\x80\x80\x80\x01", 4)),
+    std::make_tuple((1ull << 28) - 1,      TString("\xff\xff\xff\x7f", 4)),
+    std::make_tuple((1ull << 28),          TString("\x80\x80\x80\x80\x01", 5)),
+    std::make_tuple((1ull << 35) - 1,      TString("\xff\xff\xff\xff\x7f", 5)),
+    std::make_tuple((1ull << 35),          TString("\x80\x80\x80\x80\x80\x01", 6)),
+    std::make_tuple((1ull << 42) - 1,      TString("\xff\xff\xff\xff\xff\x7f", 6)),
+    std::make_tuple((1ull << 42),          TString("\x80\x80\x80\x80\x80\x80\x01", 7)),
+    std::make_tuple((1ull << 49) - 1,      TString("\xff\xff\xff\xff\xff\xff\x7f", 7)),
+    std::make_tuple((1ull << 49),          TString("\x80\x80\x80\x80\x80\x80\x80\x01", 8)),
+    std::make_tuple((1ull << 56) - 1,      TString("\xff\xff\xff\xff\xff\xff\xff\x7f", 8)),
+    std::make_tuple((1ull << 56),          TString("\x80\x80\x80\x80\x80\x80\x80\x80\x01", 9)),
+    std::make_tuple((1ull << 63) - 1,      TString("\xff\xff\xff\xff\xff\xff\xff\xff\x7f", 9)),
+    std::make_tuple((1ull << 63),          TString("\x80\x80\x80\x80\x80\x80\x80\x80\x80\x01", 10)),
+
+    // Boundary case.
+    std::make_tuple(static_cast<ui64>(-1), TString("\xff\xff\xff\xff\xff\xff\xff\xff\xff\x01", 10))
+);
+
+INSTANTIATE_TEST_SUITE_P(ValueParametrized, TWriteVarIntTest,
+    ValuesForVarIntTests);
+
+INSTANTIATE_TEST_SUITE_P(ValueParametrized, TReadVarIntTest,
+    ValuesForVarIntTests);
+
+////////////////////////////////////////////////////////////////////////////////
+
+TEST(TVarInt32Test, RandomValues)
+{
+    srand(100500); // Set seed
+    const int numberOfValues = 10000;
+
+    TStringStream stream;
+    for (int i = 0; i < numberOfValues; ++i) {
+        i32 expected = static_cast<i32>(RandomNumber<ui32>());
+        WriteVarInt32(&stream, expected);
+        i32 actual;
+        ReadVarInt32(&stream, &actual);
+        EXPECT_EQ(expected, actual)
+            << "Encoded Variant: " << EscapeC(stream.Str());
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+TEST(TVarInt64Test, RandomValues)
+{
+    srand(100500); // Set seed
+    const int numberOfValues = 10000;
+
+    TStringStream stream;
+    for (int i = 0; i < numberOfValues; ++i) {
+        i64 expected = static_cast<i64>(RandomNumber<ui64>());
+        WriteVarInt64(&stream, expected);
+        i64 actual;
+        ReadVarInt64(&stream, &actual);
+        EXPECT_EQ(expected, actual)
+            << "Encoded Variant: " << EscapeC(stream.Str());
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+} // namespace
+} // namespace NYT