//===- unittest/Support/YAMLIOTest.cpp ------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "llvm/ADT/BitmaskEnum.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/YAMLTraits.h"
#include "gmock/gmock.h"
#include "gtest/gtest.h"

using llvm::yaml::Hex16;
using llvm::yaml::Hex32;
using llvm::yaml::Hex64;
using llvm::yaml::Hex8;
using llvm::yaml::Input;
using llvm::yaml::isNumeric;
using llvm::yaml::MappingNormalization;
using llvm::yaml::MappingTraits;
using llvm::yaml::Output;
using llvm::yaml::ScalarTraits;
using ::testing::StartsWith;


static void suppressErrorMessages(const llvm::SMDiagnostic &, void *) {
}


//===----------------------------------------------------------------------===//
//  Test MappingTraits
//===----------------------------------------------------------------------===//

struct FooBar {
  int foo;
  int bar;
};
typedef std::vector<FooBar> FooBarSequence;

LLVM_YAML_IS_SEQUENCE_VECTOR(FooBar)

struct FooBarContainer {
  FooBarSequence fbs;
};

namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<FooBar> {
    static void mapping(IO &io, FooBar& fb) {
      io.mapRequired("foo",    fb.foo);
      io.mapRequired("bar",    fb.bar);
    }
  };

  template <> struct MappingTraits<FooBarContainer> {
    static void mapping(IO &io, FooBarContainer &fb) {
      io.mapRequired("fbs", fb.fbs);
    }
  };
}
}


//
// Test the reading of a yaml mapping
//
TEST(YAMLIO, TestMapRead) {
  FooBar doc;
  {
    Input yin("---\nfoo:  3\nbar:  5\n...\n");
    yin >> doc;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(doc.foo, 3);
    EXPECT_EQ(doc.bar, 5);
  }

  {
    Input yin("{foo: 3, bar: 5}");
    yin >> doc;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(doc.foo, 3);
    EXPECT_EQ(doc.bar, 5);
  }

  {
    Input yin("{\"foo\": 3\n, \"bar\": 5}");
    yin >> doc;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(doc.foo, 3);
    EXPECT_EQ(doc.bar, 5);
  }
}

TEST(YAMLIO, TestMalformedMapRead) {
  FooBar doc;
  Input yin("{foo: 3; bar: 5}", nullptr, suppressErrorMessages);
  yin >> doc;
  EXPECT_TRUE(!!yin.error());
}

TEST(YAMLIO, TestMapDuplicatedKeysRead) {
  auto testDiagnostic = [](const llvm::SMDiagnostic &Error, void *) {
    EXPECT_EQ(Error.getMessage(), "duplicated mapping key 'foo'");
  };
  FooBar doc;
  Input yin("{foo: 3, bar: 5, foo: 4}", nullptr, testDiagnostic);
  yin >> doc;
  EXPECT_TRUE(!!yin.error());
}

//
// Test the reading of a yaml sequence of mappings
//
TEST(YAMLIO, TestSequenceMapRead) {
  FooBarSequence seq;
  Input yin("---\n - foo:  3\n   bar:  5\n - foo:  7\n   bar:  9\n...\n");
  yin >> seq;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(seq.size(), 2UL);
  FooBar& map1 = seq[0];
  FooBar& map2 = seq[1];
  EXPECT_EQ(map1.foo, 3);
  EXPECT_EQ(map1.bar, 5);
  EXPECT_EQ(map2.foo, 7);
  EXPECT_EQ(map2.bar, 9);
}

//
// Test the reading of a map containing a yaml sequence of mappings
//
TEST(YAMLIO, TestContainerSequenceMapRead) {
  {
    FooBarContainer cont;
    Input yin2("---\nfbs:\n - foo: 3\n   bar: 5\n - foo: 7\n   bar: 9\n...\n");
    yin2 >> cont;

    EXPECT_FALSE(yin2.error());
    EXPECT_EQ(cont.fbs.size(), 2UL);
    EXPECT_EQ(cont.fbs[0].foo, 3);
    EXPECT_EQ(cont.fbs[0].bar, 5);
    EXPECT_EQ(cont.fbs[1].foo, 7);
    EXPECT_EQ(cont.fbs[1].bar, 9);
  }

  {
    FooBarContainer cont;
    Input yin("---\nfbs:\n...\n");
    yin >> cont;
    // Okay: Empty node represents an empty array.
    EXPECT_FALSE(yin.error());
    EXPECT_EQ(cont.fbs.size(), 0UL);
  }

  {
    FooBarContainer cont;
    Input yin("---\nfbs: !!null null\n...\n");
    yin >> cont;
    // Okay: null represents an empty array.
    EXPECT_FALSE(yin.error());
    EXPECT_EQ(cont.fbs.size(), 0UL);
  }

  {
    FooBarContainer cont;
    Input yin("---\nfbs: ~\n...\n");
    yin >> cont;
    // Okay: null represents an empty array.
    EXPECT_FALSE(yin.error());
    EXPECT_EQ(cont.fbs.size(), 0UL);
  }

  {
    FooBarContainer cont;
    Input yin("---\nfbs: null\n...\n");
    yin >> cont;
    // Okay: null represents an empty array.
    EXPECT_FALSE(yin.error());
    EXPECT_EQ(cont.fbs.size(), 0UL);
  }
}

//
// Test the reading of a map containing a malformed yaml sequence
//
TEST(YAMLIO, TestMalformedContainerSequenceMapRead) {
  {
    FooBarContainer cont;
    Input yin("---\nfbs:\n   foo: 3\n   bar: 5\n...\n", nullptr,
              suppressErrorMessages);
    yin >> cont;
    // Error: fbs is not a sequence.
    EXPECT_TRUE(!!yin.error());
    EXPECT_EQ(cont.fbs.size(), 0UL);
  }

  {
    FooBarContainer cont;
    Input yin("---\nfbs: 'scalar'\n...\n", nullptr, suppressErrorMessages);
    yin >> cont;
    // This should be an error.
    EXPECT_TRUE(!!yin.error());
    EXPECT_EQ(cont.fbs.size(), 0UL);
  }
}

//
// Test writing then reading back a sequence of mappings
//
TEST(YAMLIO, TestSequenceMapWriteAndRead) {
  std::string intermediate;
  {
    FooBar entry1;
    entry1.foo = 10;
    entry1.bar = -3;
    FooBar entry2;
    entry2.foo = 257;
    entry2.bar = 0;
    FooBarSequence seq;
    seq.push_back(entry1);
    seq.push_back(entry2);

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << seq;
  }

  {
    Input yin(intermediate);
    FooBarSequence seq2;
    yin >> seq2;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(seq2.size(), 2UL);
    FooBar& map1 = seq2[0];
    FooBar& map2 = seq2[1];
    EXPECT_EQ(map1.foo, 10);
    EXPECT_EQ(map1.bar, -3);
    EXPECT_EQ(map2.foo, 257);
    EXPECT_EQ(map2.bar, 0);
  }
}

//
// Test reading the entire struct as an enum.
//

struct FooBarEnum {
  int Foo;
  int Bar;
  bool operator==(const FooBarEnum &R) const {
    return Foo == R.Foo && Bar == R.Bar;
  }
};

namespace llvm {
namespace yaml {
template <> struct MappingTraits<FooBarEnum> {
  static void enumInput(IO &io, FooBarEnum &Val) {
    io.enumCase(Val, "OnlyFoo", FooBarEnum({1, 0}));
    io.enumCase(Val, "OnlyBar", FooBarEnum({0, 1}));
  }
  static void mapping(IO &io, FooBarEnum &Val) {
    io.mapOptional("Foo", Val.Foo);
    io.mapOptional("Bar", Val.Bar);
  }
};
} // namespace yaml
} // namespace llvm

TEST(YAMLIO, TestMapEnumRead) {
  FooBarEnum Doc;
  {
    Input Yin("OnlyFoo");
    Yin >> Doc;
    EXPECT_FALSE(Yin.error());
    EXPECT_EQ(Doc.Foo, 1);
    EXPECT_EQ(Doc.Bar, 0);
  }
  {
    Input Yin("OnlyBar");
    Yin >> Doc;
    EXPECT_FALSE(Yin.error());
    EXPECT_EQ(Doc.Foo, 0);
    EXPECT_EQ(Doc.Bar, 1);
  }
  {
    Input Yin("{Foo: 3, Bar: 5}");
    Yin >> Doc;
    EXPECT_FALSE(Yin.error());
    EXPECT_EQ(Doc.Foo, 3);
    EXPECT_EQ(Doc.Bar, 5);
  }
}

//
// Test YAML filename handling.
//
static void testErrorFilename(const llvm::SMDiagnostic &Error, void *) {
  EXPECT_EQ(Error.getFilename(), "foo.yaml");
}

TEST(YAMLIO, TestGivenFilename) {
  auto Buffer = llvm::MemoryBuffer::getMemBuffer("{ x: 42 }", "foo.yaml");
  Input yin(*Buffer, nullptr, testErrorFilename);
  FooBar Value;
  yin >> Value;

  EXPECT_TRUE(!!yin.error());
}

struct WithStringField {
  std::string str1;
  std::string str2;
  std::string str3;
};

namespace llvm {
namespace yaml {
template <> struct MappingTraits<WithStringField> {
  static void mapping(IO &io, WithStringField &fb) {
    io.mapRequired("str1", fb.str1);
    io.mapRequired("str2", fb.str2);
    io.mapRequired("str3", fb.str3);
  }
};
} // namespace yaml
} // namespace llvm

TEST(YAMLIO, MultilineStrings) {
  WithStringField Original;
  Original.str1 = "a multiline string\nfoobarbaz";
  Original.str2 = "another one\rfoobarbaz";
  Original.str3 = "a one-line string";

  std::string Serialized;
  {
    llvm::raw_string_ostream OS(Serialized);
    Output YOut(OS);
    YOut << Original;
  }
  auto Expected = "---\n"
                  "str1:            \"a multiline string\\nfoobarbaz\"\n"
                  "str2:            \"another one\\rfoobarbaz\"\n"
                  "str3:            a one-line string\n"
                  "...\n";
  ASSERT_EQ(Serialized, Expected);

  // Also check it parses back without the errors.
  WithStringField Deserialized;
  {
    Input YIn(Serialized);
    YIn >> Deserialized;
    ASSERT_FALSE(YIn.error())
        << "Parsing error occurred during deserialization. Serialized string:\n"
        << Serialized;
  }
  EXPECT_EQ(Original.str1, Deserialized.str1);
  EXPECT_EQ(Original.str2, Deserialized.str2);
  EXPECT_EQ(Original.str3, Deserialized.str3);
}

TEST(YAMLIO, NoQuotesForTab) {
  WithStringField WithTab;
  WithTab.str1 = "aba\tcaba";
  std::string Serialized;
  {
    llvm::raw_string_ostream OS(Serialized);
    Output YOut(OS);
    YOut << WithTab;
  }
  auto ExpectedPrefix = "---\n"
                        "str1:            aba\tcaba\n";
  EXPECT_THAT(Serialized, StartsWith(ExpectedPrefix));
}

//===----------------------------------------------------------------------===//
//  Test built-in types
//===----------------------------------------------------------------------===//

struct BuiltInTypes {
  llvm::StringRef str;
  std::string stdstr;
  uint64_t        u64;
  uint32_t        u32;
  uint16_t        u16;
  uint8_t         u8;
  bool            b;
  int64_t         s64;
  int32_t         s32;
  int16_t         s16;
  int8_t          s8;
  float           f;
  double          d;
  Hex8            h8;
  Hex16           h16;
  Hex32           h32;
  Hex64           h64;
};

namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<BuiltInTypes> {
    static void mapping(IO &io, BuiltInTypes& bt) {
      io.mapRequired("str",      bt.str);
      io.mapRequired("stdstr",   bt.stdstr);
      io.mapRequired("u64",      bt.u64);
      io.mapRequired("u32",      bt.u32);
      io.mapRequired("u16",      bt.u16);
      io.mapRequired("u8",       bt.u8);
      io.mapRequired("b",        bt.b);
      io.mapRequired("s64",      bt.s64);
      io.mapRequired("s32",      bt.s32);
      io.mapRequired("s16",      bt.s16);
      io.mapRequired("s8",       bt.s8);
      io.mapRequired("f",        bt.f);
      io.mapRequired("d",        bt.d);
      io.mapRequired("h8",       bt.h8);
      io.mapRequired("h16",      bt.h16);
      io.mapRequired("h32",      bt.h32);
      io.mapRequired("h64",      bt.h64);
    }
  };
}
}


//
// Test the reading of all built-in scalar conversions
//
TEST(YAMLIO, TestReadBuiltInTypes) {
  BuiltInTypes map;
  Input yin("---\n"
            "str:      hello there\n"
            "stdstr:   hello where?\n"
            "u64:      5000000000\n"
            "u32:      4000000000\n"
            "u16:      65000\n"
            "u8:       255\n"
            "b:        false\n"
            "s64:      -5000000000\n"
            "s32:      -2000000000\n"
            "s16:      -32000\n"
            "s8:       -127\n"
            "f:        137.125\n"
            "d:        -2.8625\n"
            "h8:       0xFF\n"
            "h16:      0x8765\n"
            "h32:      0xFEDCBA98\n"
            "h64:      0xFEDCBA9876543210\n"
           "...\n");
  yin >> map;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(map.str, "hello there");
  EXPECT_EQ(map.stdstr, "hello where?");
  EXPECT_EQ(map.u64, 5000000000ULL);
  EXPECT_EQ(map.u32, 4000000000U);
  EXPECT_EQ(map.u16, 65000);
  EXPECT_EQ(map.u8,  255);
  EXPECT_EQ(map.b,   false);
  EXPECT_EQ(map.s64, -5000000000LL);
  EXPECT_EQ(map.s32, -2000000000L);
  EXPECT_EQ(map.s16, -32000);
  EXPECT_EQ(map.s8,  -127);
  EXPECT_EQ(map.f,   137.125);
  EXPECT_EQ(map.d,   -2.8625);
  EXPECT_EQ(map.h8,  Hex8(255));
  EXPECT_EQ(map.h16, Hex16(0x8765));
  EXPECT_EQ(map.h32, Hex32(0xFEDCBA98));
  EXPECT_EQ(map.h64, Hex64(0xFEDCBA9876543210LL));
}


//
// Test writing then reading back all built-in scalar types
//
TEST(YAMLIO, TestReadWriteBuiltInTypes) {
  std::string intermediate;
  {
    BuiltInTypes map;
    map.str = "one two";
    map.stdstr = "three four";
    map.u64 = 6000000000ULL;
    map.u32 = 3000000000U;
    map.u16 = 50000;
    map.u8  = 254;
    map.b   = true;
    map.s64 = -6000000000LL;
    map.s32 = -2000000000;
    map.s16 = -32000;
    map.s8  = -128;
    map.f   = 3.25;
    map.d   = -2.8625;
    map.h8  = 254;
    map.h16 = 50000;
    map.h32 = 3000000000U;
    map.h64 = 6000000000LL;

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << map;
  }

  {
    Input yin(intermediate);
    BuiltInTypes map;
    yin >> map;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(map.str, "one two");
    EXPECT_EQ(map.stdstr, "three four");
    EXPECT_EQ(map.u64, 6000000000ULL);
    EXPECT_EQ(map.u32, 3000000000U);
    EXPECT_EQ(map.u16, 50000);
    EXPECT_EQ(map.u8, 254);
    EXPECT_EQ(map.b, true);
    EXPECT_EQ(map.s64, -6000000000LL);
    EXPECT_EQ(map.s32, -2000000000L);
    EXPECT_EQ(map.s16, -32000);
    EXPECT_EQ(map.s8, -128);
    EXPECT_EQ(map.f, 3.25);
    EXPECT_EQ(map.d, -2.8625);
    EXPECT_EQ(map.h8, Hex8(254));
    EXPECT_EQ(map.h16, Hex16(50000));
    EXPECT_EQ(map.h32, Hex32(3000000000U));
    EXPECT_EQ(map.h64, Hex64(6000000000LL));
  }
}

//===----------------------------------------------------------------------===//
//  Test endian-aware types
//===----------------------------------------------------------------------===//

struct EndianTypes {
  typedef llvm::support::detail::packed_endian_specific_integral<
      float, llvm::endianness::little, llvm::support::unaligned>
      ulittle_float;
  typedef llvm::support::detail::packed_endian_specific_integral<
      double, llvm::endianness::little, llvm::support::unaligned>
      ulittle_double;

  llvm::support::ulittle64_t u64;
  llvm::support::ulittle32_t u32;
  llvm::support::ulittle16_t u16;
  llvm::support::little64_t s64;
  llvm::support::little32_t s32;
  llvm::support::little16_t s16;
  ulittle_float f;
  ulittle_double d;
};

namespace llvm {
namespace yaml {
template <> struct MappingTraits<EndianTypes> {
  static void mapping(IO &io, EndianTypes &et) {
    io.mapRequired("u64", et.u64);
    io.mapRequired("u32", et.u32);
    io.mapRequired("u16", et.u16);
    io.mapRequired("s64", et.s64);
    io.mapRequired("s32", et.s32);
    io.mapRequired("s16", et.s16);
    io.mapRequired("f", et.f);
    io.mapRequired("d", et.d);
  }
};
}
}

//
// Test the reading of all endian scalar conversions
//
TEST(YAMLIO, TestReadEndianTypes) {
  EndianTypes map;
  Input yin("---\n"
            "u64:      5000000000\n"
            "u32:      4000000000\n"
            "u16:      65000\n"
            "s64:      -5000000000\n"
            "s32:      -2000000000\n"
            "s16:      -32000\n"
            "f:        3.25\n"
            "d:        -2.8625\n"
            "...\n");
  yin >> map;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(map.u64, 5000000000ULL);
  EXPECT_EQ(map.u32, 4000000000U);
  EXPECT_EQ(map.u16, 65000);
  EXPECT_EQ(map.s64, -5000000000LL);
  EXPECT_EQ(map.s32, -2000000000L);
  EXPECT_EQ(map.s16, -32000);
  EXPECT_EQ(map.f, 3.25f);
  EXPECT_EQ(map.d, -2.8625);
}

//
// Test writing then reading back all endian-aware scalar types
//
TEST(YAMLIO, TestReadWriteEndianTypes) {
  std::string intermediate;
  {
    EndianTypes map;
    map.u64 = 6000000000ULL;
    map.u32 = 3000000000U;
    map.u16 = 50000;
    map.s64 = -6000000000LL;
    map.s32 = -2000000000;
    map.s16 = -32000;
    map.f = 3.25f;
    map.d = -2.8625;

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << map;
  }

  {
    Input yin(intermediate);
    EndianTypes map;
    yin >> map;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(map.u64, 6000000000ULL);
    EXPECT_EQ(map.u32, 3000000000U);
    EXPECT_EQ(map.u16, 50000);
    EXPECT_EQ(map.s64, -6000000000LL);
    EXPECT_EQ(map.s32, -2000000000L);
    EXPECT_EQ(map.s16, -32000);
    EXPECT_EQ(map.f, 3.25f);
    EXPECT_EQ(map.d, -2.8625);
  }
}

enum class Enum : uint16_t { One, Two };
enum class BitsetEnum : uint16_t {
  ZeroOne = 0x01,
  OneZero = 0x10,
  LLVM_MARK_AS_BITMASK_ENUM(/*LargestValue*/ OneZero),
};
LLVM_ENABLE_BITMASK_ENUMS_IN_NAMESPACE();
struct EndianEnums {
  llvm::support::little_t<Enum> LittleEnum;
  llvm::support::big_t<Enum> BigEnum;
  llvm::support::little_t<BitsetEnum> LittleBitset;
  llvm::support::big_t<BitsetEnum> BigBitset;
};
namespace llvm {
namespace yaml {
template <> struct ScalarEnumerationTraits<Enum> {
  static void enumeration(IO &io, Enum &E) {
    io.enumCase(E, "One", Enum::One);
    io.enumCase(E, "Two", Enum::Two);
  }
};

template <> struct ScalarBitSetTraits<BitsetEnum> {
  static void bitset(IO &io, BitsetEnum &E) {
    io.bitSetCase(E, "ZeroOne", BitsetEnum::ZeroOne);
    io.bitSetCase(E, "OneZero", BitsetEnum::OneZero);
  }
};

template <> struct MappingTraits<EndianEnums> {
  static void mapping(IO &io, EndianEnums &EE) {
    io.mapRequired("LittleEnum", EE.LittleEnum);
    io.mapRequired("BigEnum", EE.BigEnum);
    io.mapRequired("LittleBitset", EE.LittleBitset);
    io.mapRequired("BigBitset", EE.BigBitset);
  }
};
} // namespace yaml
} // namespace llvm

TEST(YAMLIO, TestReadEndianEnums) {
  EndianEnums map;
  Input yin("---\n"
            "LittleEnum:   One\n"
            "BigEnum:      Two\n"
            "LittleBitset: [ ZeroOne ]\n"
            "BigBitset:    [ ZeroOne, OneZero ]\n"
            "...\n");
  yin >> map;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(Enum::One, map.LittleEnum);
  EXPECT_EQ(Enum::Two, map.BigEnum);
  EXPECT_EQ(BitsetEnum::ZeroOne, map.LittleBitset);
  EXPECT_EQ(BitsetEnum::ZeroOne | BitsetEnum::OneZero, map.BigBitset);
}

TEST(YAMLIO, TestReadWriteEndianEnums) {
  std::string intermediate;
  {
    EndianEnums map;
    map.LittleEnum = Enum::Two;
    map.BigEnum = Enum::One;
    map.LittleBitset = BitsetEnum::OneZero | BitsetEnum::ZeroOne;
    map.BigBitset = BitsetEnum::OneZero;

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << map;
  }

  {
    Input yin(intermediate);
    EndianEnums map;
    yin >> map;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(Enum::Two, map.LittleEnum);
    EXPECT_EQ(Enum::One, map.BigEnum);
    EXPECT_EQ(BitsetEnum::OneZero | BitsetEnum::ZeroOne, map.LittleBitset);
    EXPECT_EQ(BitsetEnum::OneZero, map.BigBitset);
  }
}

struct StringTypes {
  llvm::StringRef str1;
  llvm::StringRef str2;
  llvm::StringRef str3;
  llvm::StringRef str4;
  llvm::StringRef str5;
  llvm::StringRef str6;
  llvm::StringRef str7;
  llvm::StringRef str8;
  llvm::StringRef str9;
  llvm::StringRef str10;
  llvm::StringRef str11;
  std::string stdstr1;
  std::string stdstr2;
  std::string stdstr3;
  std::string stdstr4;
  std::string stdstr5;
  std::string stdstr6;
  std::string stdstr7;
  std::string stdstr8;
  std::string stdstr9;
  std::string stdstr10;
  std::string stdstr11;
  std::string stdstr12;
  std::string stdstr13;
};

namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<StringTypes> {
    static void mapping(IO &io, StringTypes& st) {
      io.mapRequired("str1",      st.str1);
      io.mapRequired("str2",      st.str2);
      io.mapRequired("str3",      st.str3);
      io.mapRequired("str4",      st.str4);
      io.mapRequired("str5",      st.str5);
      io.mapRequired("str6",      st.str6);
      io.mapRequired("str7",      st.str7);
      io.mapRequired("str8",      st.str8);
      io.mapRequired("str9",      st.str9);
      io.mapRequired("str10",     st.str10);
      io.mapRequired("str11",     st.str11);
      io.mapRequired("stdstr1",   st.stdstr1);
      io.mapRequired("stdstr2",   st.stdstr2);
      io.mapRequired("stdstr3",   st.stdstr3);
      io.mapRequired("stdstr4",   st.stdstr4);
      io.mapRequired("stdstr5",   st.stdstr5);
      io.mapRequired("stdstr6",   st.stdstr6);
      io.mapRequired("stdstr7",   st.stdstr7);
      io.mapRequired("stdstr8",   st.stdstr8);
      io.mapRequired("stdstr9",   st.stdstr9);
      io.mapRequired("stdstr10",  st.stdstr10);
      io.mapRequired("stdstr11",  st.stdstr11);
      io.mapRequired("stdstr12",  st.stdstr12);
      io.mapRequired("stdstr13",  st.stdstr13);
    }
  };
}
}

TEST(YAMLIO, TestReadWriteStringTypes) {
  std::string intermediate;
  {
    StringTypes map;
    map.str1 = "'aaa";
    map.str2 = "\"bbb";
    map.str3 = "`ccc";
    map.str4 = "@ddd";
    map.str5 = "";
    map.str6 = "0000000004000000";
    map.str7 = "true";
    map.str8 = "FALSE";
    map.str9 = "~";
    map.str10 = "0.2e20";
    map.str11 = "0x30";
    map.stdstr1 = "'eee";
    map.stdstr2 = "\"fff";
    map.stdstr3 = "`ggg";
    map.stdstr4 = "@hhh";
    map.stdstr5 = "";
    map.stdstr6 = "0000000004000000";
    map.stdstr7 = "true";
    map.stdstr8 = "FALSE";
    map.stdstr9 = "~";
    map.stdstr10 = "0.2e20";
    map.stdstr11 = "0x30";
    map.stdstr12 = "- match";
    map.stdstr13.assign("\0a\0b\0", 5);

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << map;
  }

  llvm::StringRef flowOut(intermediate);
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'''aaa"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'\"bbb'"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'`ccc'"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'@ddd'"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("''\n"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'0000000004000000'\n"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'true'\n"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'FALSE'\n"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'~'\n"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'0.2e20'\n"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'0x30'\n"));
  EXPECT_NE(llvm::StringRef::npos, flowOut.find("'- match'\n"));
  EXPECT_NE(std::string::npos, flowOut.find("'''eee"));
  EXPECT_NE(std::string::npos, flowOut.find("'\"fff'"));
  EXPECT_NE(std::string::npos, flowOut.find("'`ggg'"));
  EXPECT_NE(std::string::npos, flowOut.find("'@hhh'"));
  EXPECT_NE(std::string::npos, flowOut.find("''\n"));
  EXPECT_NE(std::string::npos, flowOut.find("'0000000004000000'\n"));
  EXPECT_NE(std::string::npos, flowOut.find("\"\\0a\\0b\\0\""));

  {
    Input yin(intermediate);
    StringTypes map;
    yin >> map;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(map.str1, "'aaa");
    EXPECT_EQ(map.str2, "\"bbb");
    EXPECT_EQ(map.str3, "`ccc");
    EXPECT_EQ(map.str4, "@ddd");
    EXPECT_EQ(map.str5, "");
    EXPECT_EQ(map.str6, "0000000004000000");
    EXPECT_EQ(map.stdstr1, "'eee");
    EXPECT_EQ(map.stdstr2, "\"fff");
    EXPECT_EQ(map.stdstr3, "`ggg");
    EXPECT_EQ(map.stdstr4, "@hhh");
    EXPECT_EQ(map.stdstr5, "");
    EXPECT_EQ(map.stdstr6, "0000000004000000");
    EXPECT_EQ(std::string("\0a\0b\0", 5), map.stdstr13);
  }
}

//===----------------------------------------------------------------------===//
//  Test ScalarEnumerationTraits
//===----------------------------------------------------------------------===//

enum Colors {
    cRed,
    cBlue,
    cGreen,
    cYellow
};

struct ColorMap {
  Colors      c1;
  Colors      c2;
  Colors      c3;
  Colors      c4;
  Colors      c5;
  Colors      c6;
};

namespace llvm {
namespace yaml {
  template <>
  struct ScalarEnumerationTraits<Colors> {
    static void enumeration(IO &io, Colors &value) {
      io.enumCase(value, "red",   cRed);
      io.enumCase(value, "blue",  cBlue);
      io.enumCase(value, "green", cGreen);
      io.enumCase(value, "yellow",cYellow);
    }
  };
  template <>
  struct MappingTraits<ColorMap> {
    static void mapping(IO &io, ColorMap& c) {
      io.mapRequired("c1", c.c1);
      io.mapRequired("c2", c.c2);
      io.mapRequired("c3", c.c3);
      io.mapOptional("c4", c.c4, cBlue);   // supplies default
      io.mapOptional("c5", c.c5, cYellow); // supplies default
      io.mapOptional("c6", c.c6, cRed);    // supplies default
    }
  };
}
}


//
// Test reading enumerated scalars
//
TEST(YAMLIO, TestEnumRead) {
  ColorMap map;
  Input yin("---\n"
            "c1:  blue\n"
            "c2:  red\n"
            "c3:  green\n"
            "c5:  yellow\n"
            "...\n");
  yin >> map;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(cBlue,  map.c1);
  EXPECT_EQ(cRed,   map.c2);
  EXPECT_EQ(cGreen, map.c3);
  EXPECT_EQ(cBlue,  map.c4);  // tests default
  EXPECT_EQ(cYellow,map.c5);  // tests overridden
  EXPECT_EQ(cRed,   map.c6);  // tests default
}


//===----------------------------------------------------------------------===//
//  Test ScalarBitSetTraits
//===----------------------------------------------------------------------===//

enum MyFlags {
  flagNone    = 0,
  flagBig     = 1 << 0,
  flagFlat    = 1 << 1,
  flagRound   = 1 << 2,
  flagPointy  = 1 << 3
};
inline MyFlags operator|(MyFlags a, MyFlags b) {
  return static_cast<MyFlags>(
                      static_cast<uint32_t>(a) | static_cast<uint32_t>(b));
}

struct FlagsMap {
  MyFlags     f1;
  MyFlags     f2;
  MyFlags     f3;
  MyFlags     f4;
};


namespace llvm {
namespace yaml {
  template <>
  struct ScalarBitSetTraits<MyFlags> {
    static void bitset(IO &io, MyFlags &value) {
      io.bitSetCase(value, "big",   flagBig);
      io.bitSetCase(value, "flat",  flagFlat);
      io.bitSetCase(value, "round", flagRound);
      io.bitSetCase(value, "pointy",flagPointy);
    }
  };
  template <>
  struct MappingTraits<FlagsMap> {
    static void mapping(IO &io, FlagsMap& c) {
      io.mapRequired("f1", c.f1);
      io.mapRequired("f2", c.f2);
      io.mapRequired("f3", c.f3);
      io.mapOptional("f4", c.f4, flagRound);
     }
  };
}
}


//
// Test reading flow sequence representing bit-mask values
//
TEST(YAMLIO, TestFlagsRead) {
  FlagsMap map;
  Input yin("---\n"
            "f1:  [ big ]\n"
            "f2:  [ round, flat ]\n"
            "f3:  []\n"
            "...\n");
  yin >> map;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(flagBig,              map.f1);
  EXPECT_EQ(flagRound|flagFlat,   map.f2);
  EXPECT_EQ(flagNone,             map.f3);  // check empty set
  EXPECT_EQ(flagRound,            map.f4);  // check optional key
}


//
// Test writing then reading back bit-mask values
//
TEST(YAMLIO, TestReadWriteFlags) {
  std::string intermediate;
  {
    FlagsMap map;
    map.f1 = flagBig;
    map.f2 = flagRound | flagFlat;
    map.f3 = flagNone;
    map.f4 = flagNone;

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << map;
  }

  {
    Input yin(intermediate);
    FlagsMap map2;
    yin >> map2;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(flagBig,              map2.f1);
    EXPECT_EQ(flagRound|flagFlat,   map2.f2);
    EXPECT_EQ(flagNone,             map2.f3);
    //EXPECT_EQ(flagRound,            map2.f4);  // check optional key
  }
}


//===----------------------------------------------------------------------===//
//  Test ScalarTraits
//===----------------------------------------------------------------------===//

struct MyCustomType {
  int length;
  int width;
};

struct MyCustomTypeMap {
  MyCustomType     f1;
  MyCustomType     f2;
  int              f3;
};


namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<MyCustomTypeMap> {
    static void mapping(IO &io, MyCustomTypeMap& s) {
      io.mapRequired("f1", s.f1);
      io.mapRequired("f2", s.f2);
      io.mapRequired("f3", s.f3);
     }
  };
  // MyCustomType is formatted as a yaml scalar.  A value of
  // {length=3, width=4} would be represented in yaml as "3 by 4".
  template<>
  struct ScalarTraits<MyCustomType> {
    static void output(const MyCustomType &value, void* ctxt, llvm::raw_ostream &out) {
      out << llvm::format("%d by %d", value.length, value.width);
    }
    static StringRef input(StringRef scalar, void* ctxt, MyCustomType &value) {
      size_t byStart = scalar.find("by");
      if ( byStart != StringRef::npos ) {
        StringRef lenStr = scalar.slice(0, byStart);
        lenStr = lenStr.rtrim();
        if ( lenStr.getAsInteger(0, value.length) ) {
          return "malformed length";
        }
        StringRef widthStr = scalar.drop_front(byStart+2);
        widthStr = widthStr.ltrim();
        if ( widthStr.getAsInteger(0, value.width) ) {
          return "malformed width";
        }
        return StringRef();
      }
      else {
          return "malformed by";
      }
    }
    static QuotingType mustQuote(StringRef) { return QuotingType::Single; }
  };
}
}


//
// Test writing then reading back custom values
//
TEST(YAMLIO, TestReadWriteMyCustomType) {
  std::string intermediate;
  {
    MyCustomTypeMap map;
    map.f1.length = 1;
    map.f1.width  = 4;
    map.f2.length = 100;
    map.f2.width  = 400;
    map.f3 = 10;

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << map;
  }

  {
    Input yin(intermediate);
    MyCustomTypeMap map2;
    yin >> map2;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(1,      map2.f1.length);
    EXPECT_EQ(4,      map2.f1.width);
    EXPECT_EQ(100,    map2.f2.length);
    EXPECT_EQ(400,    map2.f2.width);
    EXPECT_EQ(10,     map2.f3);
  }
}


//===----------------------------------------------------------------------===//
//  Test BlockScalarTraits
//===----------------------------------------------------------------------===//

struct MultilineStringType {
  std::string str;
};

struct MultilineStringTypeMap {
  MultilineStringType name;
  MultilineStringType description;
  MultilineStringType ingredients;
  MultilineStringType recipes;
  MultilineStringType warningLabels;
  MultilineStringType documentation;
  int price;
};

namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<MultilineStringTypeMap> {
    static void mapping(IO &io, MultilineStringTypeMap& s) {
      io.mapRequired("name", s.name);
      io.mapRequired("description", s.description);
      io.mapRequired("ingredients", s.ingredients);
      io.mapRequired("recipes", s.recipes);
      io.mapRequired("warningLabels", s.warningLabels);
      io.mapRequired("documentation", s.documentation);
      io.mapRequired("price", s.price);
     }
  };

  // MultilineStringType is formatted as a yaml block literal scalar. A value of
  // "Hello\nWorld" would be represented in yaml as
  //  |
  //    Hello
  //    World
  template <>
  struct BlockScalarTraits<MultilineStringType> {
    static void output(const MultilineStringType &value, void *ctxt,
                       llvm::raw_ostream &out) {
      out << value.str;
    }
    static StringRef input(StringRef scalar, void *ctxt,
                           MultilineStringType &value) {
      value.str = scalar.str();
      return StringRef();
    }
  };
}
}

LLVM_YAML_IS_DOCUMENT_LIST_VECTOR(MultilineStringType)

//
// Test writing then reading back custom values
//
TEST(YAMLIO, TestReadWriteMultilineStringType) {
  std::string intermediate;
  {
    MultilineStringTypeMap map;
    map.name.str = "An Item";
    map.description.str = "Hello\nWorld";
    map.ingredients.str = "SubItem 1\nSub Item 2\n\nSub Item 3\n";
    map.recipes.str = "\n\nTest 1\n\n\n";
    map.warningLabels.str = "";
    map.documentation.str = "\n\n";
    map.price = 350;

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << map;
  }
  {
    Input yin(intermediate);
    MultilineStringTypeMap map2;
    yin >> map2;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(map2.name.str, "An Item\n");
    EXPECT_EQ(map2.description.str, "Hello\nWorld\n");
    EXPECT_EQ(map2.ingredients.str, "SubItem 1\nSub Item 2\n\nSub Item 3\n");
    EXPECT_EQ(map2.recipes.str, "\n\nTest 1\n");
    EXPECT_TRUE(map2.warningLabels.str.empty());
    EXPECT_TRUE(map2.documentation.str.empty());
    EXPECT_EQ(map2.price, 350);
  }
}

//
// Test writing then reading back custom values
//
TEST(YAMLIO, TestReadWriteBlockScalarDocuments) {
  std::string intermediate;
  {
    std::vector<MultilineStringType> documents;
    MultilineStringType doc;
    doc.str = "Hello\nWorld";
    documents.push_back(doc);

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << documents;

    // Verify that the block scalar header was written out on the same line
    // as the document marker.
    EXPECT_NE(llvm::StringRef::npos,
              llvm::StringRef(intermediate).find("--- |"));
  }
  {
    Input yin(intermediate);
    std::vector<MultilineStringType> documents2;
    yin >> documents2;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(documents2.size(), size_t(1));
    EXPECT_EQ(documents2[0].str, "Hello\nWorld\n");
  }
}

TEST(YAMLIO, TestReadWriteBlockScalarValue) {
  std::string intermediate;
  {
    MultilineStringType doc;
    doc.str = "Just a block\nscalar doc";

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << doc;
  }
  {
    Input yin(intermediate);
    MultilineStringType doc;
    yin >> doc;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(doc.str, "Just a block\nscalar doc\n");
  }
}

//===----------------------------------------------------------------------===//
//  Test flow sequences
//===----------------------------------------------------------------------===//

LLVM_YAML_STRONG_TYPEDEF(int, MyNumber)
LLVM_YAML_IS_FLOW_SEQUENCE_VECTOR(MyNumber)
LLVM_YAML_STRONG_TYPEDEF(llvm::StringRef, MyString)
LLVM_YAML_IS_FLOW_SEQUENCE_VECTOR(MyString)

namespace llvm {
namespace yaml {
  template<>
  struct ScalarTraits<MyNumber> {
    static void output(const MyNumber &value, void *, llvm::raw_ostream &out) {
      out << value;
    }

    static StringRef input(StringRef scalar, void *, MyNumber &value) {
      long long n;
      if ( getAsSignedInteger(scalar, 0, n) )
        return "invalid number";
      value = n;
      return StringRef();
    }

    static QuotingType mustQuote(StringRef) { return QuotingType::None; }
  };

  template <> struct ScalarTraits<MyString> {
    using Impl = ScalarTraits<StringRef>;
    static void output(const MyString &V, void *Ctx, raw_ostream &OS) {
      Impl::output(V, Ctx, OS);
    }
    static StringRef input(StringRef S, void *Ctx, MyString &V) {
      return Impl::input(S, Ctx, V.value);
    }
    static QuotingType mustQuote(StringRef S) {
      return Impl::mustQuote(S);
    }
  };
}
}

struct NameAndNumbers {
  llvm::StringRef               name;
  std::vector<MyString>         strings;
  std::vector<MyNumber>         single;
  std::vector<MyNumber>         numbers;
};

namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<NameAndNumbers> {
    static void mapping(IO &io, NameAndNumbers& nn) {
      io.mapRequired("name",     nn.name);
      io.mapRequired("strings",  nn.strings);
      io.mapRequired("single",   nn.single);
      io.mapRequired("numbers",  nn.numbers);
    }
  };
}
}

typedef std::vector<MyNumber> MyNumberFlowSequence;

LLVM_YAML_IS_SEQUENCE_VECTOR(MyNumberFlowSequence)

struct NameAndNumbersFlow {
  llvm::StringRef                    name;
  std::vector<MyNumberFlowSequence>  sequenceOfNumbers;
};

namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<NameAndNumbersFlow> {
    static void mapping(IO &io, NameAndNumbersFlow& nn) {
      io.mapRequired("name",     nn.name);
      io.mapRequired("sequenceOfNumbers",  nn.sequenceOfNumbers);
    }
  };
}
}

//
// Test writing then reading back custom values
//
TEST(YAMLIO, TestReadWriteMyFlowSequence) {
  std::string intermediate;
  {
    NameAndNumbers map;
    map.name  = "hello";
    map.strings.push_back(llvm::StringRef("one"));
    map.strings.push_back(llvm::StringRef("two"));
    map.single.push_back(1);
    map.numbers.push_back(10);
    map.numbers.push_back(-30);
    map.numbers.push_back(1024);

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << map;

    // Verify sequences were written in flow style
    llvm::StringRef flowOut(intermediate);
    EXPECT_NE(llvm::StringRef::npos, flowOut.find("one, two"));
    EXPECT_NE(llvm::StringRef::npos, flowOut.find("10, -30, 1024"));
  }

  {
    Input yin(intermediate);
    NameAndNumbers map2;
    yin >> map2;

    EXPECT_FALSE(yin.error());
    EXPECT_TRUE(map2.name == "hello");
    EXPECT_EQ(map2.strings.size(), 2UL);
    EXPECT_TRUE(map2.strings[0].value == "one");
    EXPECT_TRUE(map2.strings[1].value == "two");
    EXPECT_EQ(map2.single.size(), 1UL);
    EXPECT_EQ(1,       map2.single[0]);
    EXPECT_EQ(map2.numbers.size(), 3UL);
    EXPECT_EQ(10,      map2.numbers[0]);
    EXPECT_EQ(-30,     map2.numbers[1]);
    EXPECT_EQ(1024,    map2.numbers[2]);
  }
}


//
// Test writing then reading back a sequence of flow sequences.
//
TEST(YAMLIO, TestReadWriteSequenceOfMyFlowSequence) {
  std::string intermediate;
  {
    NameAndNumbersFlow map;
    map.name  = "hello";
    MyNumberFlowSequence single = { 0 };
    MyNumberFlowSequence numbers = { 12, 1, -512 };
    map.sequenceOfNumbers.push_back(single);
    map.sequenceOfNumbers.push_back(numbers);
    map.sequenceOfNumbers.push_back(MyNumberFlowSequence());

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << map;

    // Verify sequences were written in flow style
    // and that the parent sequence used '-'.
    llvm::StringRef flowOut(intermediate);
    EXPECT_NE(llvm::StringRef::npos, flowOut.find("- [ 0 ]"));
    EXPECT_NE(llvm::StringRef::npos, flowOut.find("- [ 12, 1, -512 ]"));
    EXPECT_NE(llvm::StringRef::npos, flowOut.find("- [  ]"));
  }

  {
    Input yin(intermediate);
    NameAndNumbersFlow map2;
    yin >> map2;

    EXPECT_FALSE(yin.error());
    EXPECT_TRUE(map2.name == "hello");
    EXPECT_EQ(map2.sequenceOfNumbers.size(), 3UL);
    EXPECT_EQ(map2.sequenceOfNumbers[0].size(), 1UL);
    EXPECT_EQ(0,    map2.sequenceOfNumbers[0][0]);
    EXPECT_EQ(map2.sequenceOfNumbers[1].size(), 3UL);
    EXPECT_EQ(12,   map2.sequenceOfNumbers[1][0]);
    EXPECT_EQ(1,    map2.sequenceOfNumbers[1][1]);
    EXPECT_EQ(-512, map2.sequenceOfNumbers[1][2]);
    EXPECT_TRUE(map2.sequenceOfNumbers[2].empty());
  }
}

//===----------------------------------------------------------------------===//
//  Test normalizing/denormalizing
//===----------------------------------------------------------------------===//

LLVM_YAML_STRONG_TYPEDEF(uint32_t, TotalSeconds)

typedef std::vector<TotalSeconds> SecondsSequence;

LLVM_YAML_IS_SEQUENCE_VECTOR(TotalSeconds)


namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<TotalSeconds> {

    class NormalizedSeconds {
    public:
      NormalizedSeconds(IO &io)
        : hours(0), minutes(0), seconds(0) {
      }
      NormalizedSeconds(IO &, TotalSeconds &secs)
        : hours(secs/3600),
          minutes((secs - (hours*3600))/60),
          seconds(secs % 60) {
      }
      TotalSeconds denormalize(IO &) {
        return TotalSeconds(hours*3600 + minutes*60 + seconds);
      }

      uint32_t     hours;
      uint8_t      minutes;
      uint8_t      seconds;
    };

    static void mapping(IO &io, TotalSeconds &secs) {
      MappingNormalization<NormalizedSeconds, TotalSeconds> keys(io, secs);

      io.mapOptional("hours", keys->hours, 0);
      io.mapOptional("minutes", keys->minutes, 0);
      io.mapRequired("seconds",  keys->seconds);
    }
  };
}
}


//
// Test the reading of a yaml sequence of mappings
//
TEST(YAMLIO, TestReadMySecondsSequence) {
  SecondsSequence seq;
  Input yin("---\n - hours:  1\n   seconds:  5\n - seconds:  59\n...\n");
  yin >> seq;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(seq.size(), 2UL);
  EXPECT_EQ(seq[0], 3605U);
  EXPECT_EQ(seq[1], 59U);
}


//
// Test writing then reading back custom values
//
TEST(YAMLIO, TestReadWriteMySecondsSequence) {
  std::string intermediate;
  {
    SecondsSequence seq;
    seq.push_back(4000);
    seq.push_back(500);
    seq.push_back(59);

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << seq;
  }
  {
    Input yin(intermediate);
    SecondsSequence seq2;
    yin >> seq2;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(seq2.size(), 3UL);
    EXPECT_EQ(seq2[0], 4000U);
    EXPECT_EQ(seq2[1], 500U);
    EXPECT_EQ(seq2[2], 59U);
  }
}

//===----------------------------------------------------------------------===//
//  Test nested sequence
//===----------------------------------------------------------------------===//
using NestedStringSeq1 = llvm::SmallVector<std::string, 2>;
using NestedStringSeq2 = std::array<NestedStringSeq1, 2>;
using NestedStringSeq3 = std::vector<NestedStringSeq2>;

LLVM_YAML_IS_SEQUENCE_VECTOR(NestedStringSeq1)
LLVM_YAML_IS_SEQUENCE_VECTOR(NestedStringSeq2)

struct MappedStringSeq3 {
  NestedStringSeq3 Seq3;
};

template <> struct llvm::yaml::MappingTraits<MappedStringSeq3> {
  static void mapping(IO &io, MappedStringSeq3 &seq) {
    io.mapRequired("Seq3", seq.Seq3);
  }
};

using NestedIntSeq1 = std::array<int, 2>;
using NestedIntSeq2 = std::array<NestedIntSeq1, 2>;
using NestedIntSeq3 = std::array<NestedIntSeq2, 2>;

LLVM_YAML_IS_SEQUENCE_VECTOR(NestedIntSeq1)
LLVM_YAML_IS_SEQUENCE_VECTOR(NestedIntSeq2)

template <typename Ty> std::string ParseAndEmit(llvm::StringRef YAML) {
  Ty seq3;
  Input yin(YAML);
  yin >> seq3;
  std::string out;
  llvm::raw_string_ostream ostr(out);
  Output yout(ostr);
  yout << seq3;
  return out;
}

TEST(YAMLIO, TestNestedSequence) {
  {
    llvm::StringRef Seq3YAML(R"YAML(---
- - [ 1000, 1001 ]
  - [ 1010, 1011 ]
- - [ 1100, 1101 ]
  - [ 1110, 1111 ]
...
)YAML");

    std::string out = ParseAndEmit<NestedIntSeq3>(Seq3YAML);
    EXPECT_EQ(out, Seq3YAML);
  }

  {
    llvm::StringRef Seq3YAML(R"YAML(---
- - - '000'
    - '001'
  - - '010'
    - '011'
- - - '100'
    - '101'
  - - '110'
    - '111'
...
)YAML");

    std::string out = ParseAndEmit<NestedStringSeq3>(Seq3YAML);
    EXPECT_EQ(out, Seq3YAML);
  }

  {
    llvm::StringRef Seq3YAML(R"YAML(---
Seq3:
  - - - '000'
      - '001'
    - - '010'
      - '011'
  - - - '100'
      - '101'
    - - '110'
      - '111'
...
)YAML");

    std::string out = ParseAndEmit<MappedStringSeq3>(Seq3YAML);
    EXPECT_EQ(out, Seq3YAML);
  }
}

//===----------------------------------------------------------------------===//
//  Test dynamic typing
//===----------------------------------------------------------------------===//

enum AFlags {
    a1,
    a2,
    a3
};

enum BFlags {
    b1,
    b2,
    b3
};

enum Kind {
    kindA,
    kindB
};

struct KindAndFlags {
  KindAndFlags() : kind(kindA), flags(0) { }
  KindAndFlags(Kind k, uint32_t f) : kind(k), flags(f) { }
  Kind        kind;
  uint32_t    flags;
};

typedef std::vector<KindAndFlags> KindAndFlagsSequence;

LLVM_YAML_IS_SEQUENCE_VECTOR(KindAndFlags)

namespace llvm {
namespace yaml {
  template <>
  struct ScalarEnumerationTraits<AFlags> {
    static void enumeration(IO &io, AFlags &value) {
      io.enumCase(value, "a1",  a1);
      io.enumCase(value, "a2",  a2);
      io.enumCase(value, "a3",  a3);
    }
  };
  template <>
  struct ScalarEnumerationTraits<BFlags> {
    static void enumeration(IO &io, BFlags &value) {
      io.enumCase(value, "b1",  b1);
      io.enumCase(value, "b2",  b2);
      io.enumCase(value, "b3",  b3);
    }
  };
  template <>
  struct ScalarEnumerationTraits<Kind> {
    static void enumeration(IO &io, Kind &value) {
      io.enumCase(value, "A",  kindA);
      io.enumCase(value, "B",  kindB);
    }
  };
  template <>
  struct MappingTraits<KindAndFlags> {
    static void mapping(IO &io, KindAndFlags& kf) {
      io.mapRequired("kind",  kf.kind);
      // Type of "flags" field varies depending on "kind" field.
      // Use memcpy here to avoid breaking strict aliasing rules.
      if (kf.kind == kindA) {
        AFlags aflags = static_cast<AFlags>(kf.flags);
        io.mapRequired("flags", aflags);
        kf.flags = aflags;
      } else {
        BFlags bflags = static_cast<BFlags>(kf.flags);
        io.mapRequired("flags", bflags);
        kf.flags = bflags;
      }
    }
  };
}
}


//
// Test the reading of a yaml sequence dynamic types
//
TEST(YAMLIO, TestReadKindAndFlagsSequence) {
  KindAndFlagsSequence seq;
  Input yin("---\n - kind:  A\n   flags:  a2\n - kind:  B\n   flags:  b1\n...\n");
  yin >> seq;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(seq.size(), 2UL);
  EXPECT_EQ(seq[0].kind,  kindA);
  EXPECT_EQ(seq[0].flags, (uint32_t)a2);
  EXPECT_EQ(seq[1].kind,  kindB);
  EXPECT_EQ(seq[1].flags, (uint32_t)b1);
}

//
// Test writing then reading back dynamic types
//
TEST(YAMLIO, TestReadWriteKindAndFlagsSequence) {
  std::string intermediate;
  {
    KindAndFlagsSequence seq;
    seq.push_back(KindAndFlags(kindA,a1));
    seq.push_back(KindAndFlags(kindB,b1));
    seq.push_back(KindAndFlags(kindA,a2));
    seq.push_back(KindAndFlags(kindB,b2));
    seq.push_back(KindAndFlags(kindA,a3));

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << seq;
  }
  {
    Input yin(intermediate);
    KindAndFlagsSequence seq2;
    yin >> seq2;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(seq2.size(), 5UL);
    EXPECT_EQ(seq2[0].kind,  kindA);
    EXPECT_EQ(seq2[0].flags, (uint32_t)a1);
    EXPECT_EQ(seq2[1].kind,  kindB);
    EXPECT_EQ(seq2[1].flags, (uint32_t)b1);
    EXPECT_EQ(seq2[2].kind,  kindA);
    EXPECT_EQ(seq2[2].flags, (uint32_t)a2);
    EXPECT_EQ(seq2[3].kind,  kindB);
    EXPECT_EQ(seq2[3].flags, (uint32_t)b2);
    EXPECT_EQ(seq2[4].kind,  kindA);
    EXPECT_EQ(seq2[4].flags, (uint32_t)a3);
  }
}


//===----------------------------------------------------------------------===//
//  Test document list
//===----------------------------------------------------------------------===//

struct FooBarMap {
  int foo;
  int bar;
};
typedef std::vector<FooBarMap> FooBarMapDocumentList;

LLVM_YAML_IS_DOCUMENT_LIST_VECTOR(FooBarMap)


namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<FooBarMap> {
    static void mapping(IO &io, FooBarMap& fb) {
      io.mapRequired("foo",    fb.foo);
      io.mapRequired("bar",    fb.bar);
    }
  };
}
}


//
// Test the reading of a yaml mapping
//
TEST(YAMLIO, TestDocRead) {
  FooBarMap doc;
  Input yin("---\nfoo:  3\nbar:  5\n...\n");
  yin >> doc;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(doc.foo, 3);
  EXPECT_EQ(doc.bar,5);
}


//
// Test writing then reading back a sequence of mappings
//
TEST(YAMLIO, TestSequenceDocListWriteAndRead) {
  std::string intermediate;
  {
    FooBarMap doc1;
    doc1.foo = 10;
    doc1.bar = -3;
    FooBarMap doc2;
    doc2.foo = 257;
    doc2.bar = 0;
    std::vector<FooBarMap> docList;
    docList.push_back(doc1);
    docList.push_back(doc2);

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << docList;
  }


  {
    Input yin(intermediate);
    std::vector<FooBarMap> docList2;
    yin >> docList2;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(docList2.size(), 2UL);
    FooBarMap& map1 = docList2[0];
    FooBarMap& map2 = docList2[1];
    EXPECT_EQ(map1.foo, 10);
    EXPECT_EQ(map1.bar, -3);
    EXPECT_EQ(map2.foo, 257);
    EXPECT_EQ(map2.bar, 0);
  }
}

//===----------------------------------------------------------------------===//
//  Test document tags
//===----------------------------------------------------------------------===//

struct MyDouble {
  MyDouble() : value(0.0) { }
  MyDouble(double x) : value(x) { }
  double value;
};

LLVM_YAML_IS_DOCUMENT_LIST_VECTOR(MyDouble)


namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<MyDouble> {
    static void mapping(IO &io, MyDouble &d) {
      if (io.mapTag("!decimal", true)) {
        mappingDecimal(io, d);
      } else if (io.mapTag("!fraction")) {
        mappingFraction(io, d);
      }
    }
    static void mappingDecimal(IO &io, MyDouble &d) {
      io.mapRequired("value", d.value);
    }
    static void mappingFraction(IO &io, MyDouble &d) {
        double num, denom;
        io.mapRequired("numerator",      num);
        io.mapRequired("denominator",    denom);
        // convert fraction to double
        d.value = num/denom;
    }
  };
 }
}


//
// Test the reading of two different tagged yaml documents.
//
TEST(YAMLIO, TestTaggedDocuments) {
  std::vector<MyDouble> docList;
  Input yin("--- !decimal\nvalue:  3.0\n"
            "--- !fraction\nnumerator:  9.0\ndenominator:  2\n...\n");
  yin >> docList;
  EXPECT_FALSE(yin.error());
  EXPECT_EQ(docList.size(), 2UL);
  EXPECT_EQ(docList[0].value, 3.0);
  EXPECT_EQ(docList[1].value, 4.5);
}


//
// Test writing then reading back tagged documents
//
TEST(YAMLIO, TestTaggedDocumentsWriteAndRead) {
  std::string intermediate;
  {
    MyDouble a(10.25);
    MyDouble b(-3.75);
    std::vector<MyDouble> docList;
    docList.push_back(a);
    docList.push_back(b);

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << docList;
  }

  {
    Input yin(intermediate);
    std::vector<MyDouble> docList2;
    yin >> docList2;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(docList2.size(), 2UL);
    EXPECT_EQ(docList2[0].value, 10.25);
    EXPECT_EQ(docList2[1].value, -3.75);
  }
}


//===----------------------------------------------------------------------===//
//  Test mapping validation
//===----------------------------------------------------------------------===//

struct MyValidation {
  double value;
};

LLVM_YAML_IS_DOCUMENT_LIST_VECTOR(MyValidation)

namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<MyValidation> {
    static void mapping(IO &io, MyValidation &d) {
        io.mapRequired("value", d.value);
    }
    static std::string validate(IO &io, MyValidation &d) {
        if (d.value < 0)
          return "negative value";
        return {};
    }
  };
 }
}


//
// Test that validate() is called and complains about the negative value.
//
TEST(YAMLIO, TestValidatingInput) {
  std::vector<MyValidation> docList;
  Input yin("--- \nvalue:  3.0\n"
            "--- \nvalue:  -1.0\n...\n",
            nullptr, suppressErrorMessages);
  yin >> docList;
  EXPECT_TRUE(!!yin.error());
}

//===----------------------------------------------------------------------===//
//  Test flow mapping
//===----------------------------------------------------------------------===//

struct FlowFooBar {
  int foo;
  int bar;

  FlowFooBar() : foo(0), bar(0) {}
  FlowFooBar(int foo, int bar) : foo(foo), bar(bar) {}
};

typedef std::vector<FlowFooBar> FlowFooBarSequence;

LLVM_YAML_IS_SEQUENCE_VECTOR(FlowFooBar)

struct FlowFooBarDoc {
  FlowFooBar attribute;
  FlowFooBarSequence seq;
};

namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<FlowFooBar> {
    static void mapping(IO &io, FlowFooBar &fb) {
      io.mapRequired("foo", fb.foo);
      io.mapRequired("bar", fb.bar);
    }

    static const bool flow = true;
  };

  template <>
  struct MappingTraits<FlowFooBarDoc> {
    static void mapping(IO &io, FlowFooBarDoc &fb) {
      io.mapRequired("attribute", fb.attribute);
      io.mapRequired("seq", fb.seq);
    }
  };
}
}

//
// Test writing then reading back custom mappings
//
TEST(YAMLIO, TestReadWriteMyFlowMapping) {
  std::string intermediate;
  {
    FlowFooBarDoc doc;
    doc.attribute = FlowFooBar(42, 907);
    doc.seq.push_back(FlowFooBar(1, 2));
    doc.seq.push_back(FlowFooBar(0, 0));
    doc.seq.push_back(FlowFooBar(-1, 1024));

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << doc;

    // Verify that mappings were written in flow style
    llvm::StringRef flowOut(intermediate);
    EXPECT_NE(llvm::StringRef::npos, flowOut.find("{ foo: 42, bar: 907 }"));
    EXPECT_NE(llvm::StringRef::npos, flowOut.find("- { foo: 1, bar: 2 }"));
    EXPECT_NE(llvm::StringRef::npos, flowOut.find("- { foo: 0, bar: 0 }"));
    EXPECT_NE(llvm::StringRef::npos, flowOut.find("- { foo: -1, bar: 1024 }"));
  }

  {
    Input yin(intermediate);
    FlowFooBarDoc doc2;
    yin >> doc2;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(doc2.attribute.foo, 42);
    EXPECT_EQ(doc2.attribute.bar, 907);
    EXPECT_EQ(doc2.seq.size(), 3UL);
    EXPECT_EQ(doc2.seq[0].foo, 1);
    EXPECT_EQ(doc2.seq[0].bar, 2);
    EXPECT_EQ(doc2.seq[1].foo, 0);
    EXPECT_EQ(doc2.seq[1].bar, 0);
    EXPECT_EQ(doc2.seq[2].foo, -1);
    EXPECT_EQ(doc2.seq[2].bar, 1024);
  }
}

//===----------------------------------------------------------------------===//
//  Test error handling
//===----------------------------------------------------------------------===//

//
// Test error handling of unknown enumerated scalar
//
TEST(YAMLIO, TestColorsReadError) {
  ColorMap map;
  Input yin("---\n"
            "c1:  blue\n"
            "c2:  purple\n"
            "c3:  green\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> map;
  EXPECT_TRUE(!!yin.error());
}


//
// Test error handling of flow sequence with unknown value
//
TEST(YAMLIO, TestFlagsReadError) {
  FlagsMap map;
  Input yin("---\n"
            "f1:  [ big ]\n"
            "f2:  [ round, hollow ]\n"
            "f3:  []\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> map;

  EXPECT_TRUE(!!yin.error());
}


//
// Test error handling reading built-in uint8_t type
//
TEST(YAMLIO, TestReadBuiltInTypesUint8Error) {
  std::vector<uint8_t> seq;
  Input yin("---\n"
            "- 255\n"
            "- 0\n"
            "- 257\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}


//
// Test error handling reading built-in uint16_t type
//
TEST(YAMLIO, TestReadBuiltInTypesUint16Error) {
  std::vector<uint16_t> seq;
  Input yin("---\n"
            "- 65535\n"
            "- 0\n"
            "- 66000\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}


//
// Test error handling reading built-in uint32_t type
//
TEST(YAMLIO, TestReadBuiltInTypesUint32Error) {
  std::vector<uint32_t> seq;
  Input yin("---\n"
            "- 4000000000\n"
            "- 0\n"
            "- 5000000000\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}


//
// Test error handling reading built-in uint64_t type
//
TEST(YAMLIO, TestReadBuiltInTypesUint64Error) {
  std::vector<uint64_t> seq;
  Input yin("---\n"
            "- 18446744073709551615\n"
            "- 0\n"
            "- 19446744073709551615\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}


//
// Test error handling reading built-in int8_t type
//
TEST(YAMLIO, TestReadBuiltInTypesint8OverError) {
  std::vector<int8_t> seq;
  Input yin("---\n"
            "- -128\n"
            "- 0\n"
            "- 127\n"
            "- 128\n"
           "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}

//
// Test error handling reading built-in int8_t type
//
TEST(YAMLIO, TestReadBuiltInTypesint8UnderError) {
  std::vector<int8_t> seq;
  Input yin("---\n"
            "- -128\n"
            "- 0\n"
            "- 127\n"
            "- -129\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}


//
// Test error handling reading built-in int16_t type
//
TEST(YAMLIO, TestReadBuiltInTypesint16UnderError) {
  std::vector<int16_t> seq;
  Input yin("---\n"
            "- 32767\n"
            "- 0\n"
            "- -32768\n"
            "- -32769\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}


//
// Test error handling reading built-in int16_t type
//
TEST(YAMLIO, TestReadBuiltInTypesint16OverError) {
  std::vector<int16_t> seq;
  Input yin("---\n"
            "- 32767\n"
            "- 0\n"
            "- -32768\n"
            "- 32768\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}


//
// Test error handling reading built-in int32_t type
//
TEST(YAMLIO, TestReadBuiltInTypesint32UnderError) {
  std::vector<int32_t> seq;
  Input yin("---\n"
            "- 2147483647\n"
            "- 0\n"
            "- -2147483648\n"
            "- -2147483649\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}

//
// Test error handling reading built-in int32_t type
//
TEST(YAMLIO, TestReadBuiltInTypesint32OverError) {
  std::vector<int32_t> seq;
  Input yin("---\n"
            "- 2147483647\n"
            "- 0\n"
            "- -2147483648\n"
            "- 2147483649\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}


//
// Test error handling reading built-in int64_t type
//
TEST(YAMLIO, TestReadBuiltInTypesint64UnderError) {
  std::vector<int64_t> seq;
  Input yin("---\n"
            "- -9223372036854775808\n"
            "- 0\n"
            "- 9223372036854775807\n"
            "- -9223372036854775809\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}

//
// Test error handling reading built-in int64_t type
//
TEST(YAMLIO, TestReadBuiltInTypesint64OverError) {
  std::vector<int64_t> seq;
  Input yin("---\n"
            "- -9223372036854775808\n"
            "- 0\n"
            "- 9223372036854775807\n"
            "- 9223372036854775809\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}

//
// Test error handling reading built-in float type
//
TEST(YAMLIO, TestReadBuiltInTypesFloatError) {
  std::vector<float> seq;
  Input yin("---\n"
            "- 0.0\n"
            "- 1000.1\n"
            "- -123.456\n"
            "- 1.2.3\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}

//
// Test error handling reading built-in float type
//
TEST(YAMLIO, TestReadBuiltInTypesDoubleError) {
  std::vector<double> seq;
  Input yin("---\n"
            "- 0.0\n"
            "- 1000.1\n"
            "- -123.456\n"
            "- 1.2.3\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());
}

//
// Test error handling reading built-in Hex8 type
//
TEST(YAMLIO, TestReadBuiltInTypesHex8Error) {
  std::vector<Hex8> seq;
  Input yin("---\n"
            "- 0x12\n"
            "- 0xFE\n"
            "- 0x123\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;
  EXPECT_TRUE(!!yin.error());

  std::vector<Hex8> seq2;
  Input yin2("---\n"
             "[ 0x12, 0xFE, 0x123 ]\n"
             "...\n",
             /*Ctxt=*/nullptr, suppressErrorMessages);
  yin2 >> seq2;
  EXPECT_TRUE(!!yin2.error());

  EXPECT_EQ(seq.size(), 3u);
  EXPECT_EQ(seq.size(), seq2.size());
  for (size_t i = 0; i < seq.size(); ++i)
    EXPECT_EQ(seq[i], seq2[i]);
}


//
// Test error handling reading built-in Hex16 type
//
TEST(YAMLIO, TestReadBuiltInTypesHex16Error) {
  std::vector<Hex16> seq;
  Input yin("---\n"
            "- 0x0012\n"
            "- 0xFEFF\n"
            "- 0x12345\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;
  EXPECT_TRUE(!!yin.error());

  std::vector<Hex16> seq2;
  Input yin2("---\n"
             "[ 0x0012, 0xFEFF, 0x12345 ]\n"
             "...\n",
             /*Ctxt=*/nullptr, suppressErrorMessages);
  yin2 >> seq2;
  EXPECT_TRUE(!!yin2.error());

  EXPECT_EQ(seq.size(), 3u);
  EXPECT_EQ(seq.size(), seq2.size());
  for (size_t i = 0; i < seq.size(); ++i)
    EXPECT_EQ(seq[i], seq2[i]);
}

//
// Test error handling reading built-in Hex32 type
//
TEST(YAMLIO, TestReadBuiltInTypesHex32Error) {
  std::vector<Hex32> seq;
  Input yin("---\n"
            "- 0x0012\n"
            "- 0xFEFF0000\n"
            "- 0x1234556789\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;

  EXPECT_TRUE(!!yin.error());

  std::vector<Hex32> seq2;
  Input yin2("---\n"
             "[ 0x0012, 0xFEFF0000, 0x1234556789 ]\n"
             "...\n",
             /*Ctxt=*/nullptr, suppressErrorMessages);
  yin2 >> seq2;
  EXPECT_TRUE(!!yin2.error());

  EXPECT_EQ(seq.size(), 3u);
  EXPECT_EQ(seq.size(), seq2.size());
  for (size_t i = 0; i < seq.size(); ++i)
    EXPECT_EQ(seq[i], seq2[i]);
}

//
// Test error handling reading built-in Hex64 type
//
TEST(YAMLIO, TestReadBuiltInTypesHex64Error) {
  std::vector<Hex64> seq;
  Input yin("---\n"
            "- 0x0012\n"
            "- 0xFFEEDDCCBBAA9988\n"
            "- 0x12345567890ABCDEF0\n"
            "...\n",
            /*Ctxt=*/nullptr,
            suppressErrorMessages);
  yin >> seq;
  EXPECT_TRUE(!!yin.error());

  std::vector<Hex64> seq2;
  Input yin2("---\n"
             "[ 0x0012, 0xFFEEDDCCBBAA9988, 0x12345567890ABCDEF0 ]\n"
             "...\n",
             /*Ctxt=*/nullptr, suppressErrorMessages);
  yin2 >> seq2;
  EXPECT_TRUE(!!yin2.error());

  EXPECT_EQ(seq.size(), 3u);
  EXPECT_EQ(seq.size(), seq2.size());
  for (size_t i = 0; i < seq.size(); ++i)
    EXPECT_EQ(seq[i], seq2[i]);
}

TEST(YAMLIO, TestMalformedMapFailsGracefully) {
  FooBar doc;
  {
    // We pass the suppressErrorMessages handler to handle the error
    // message generated in the constructor of Input.
    Input yin("{foo:3, bar: 5}", /*Ctxt=*/nullptr, suppressErrorMessages);
    yin >> doc;
    EXPECT_TRUE(!!yin.error());
  }

  {
    Input yin("---\nfoo:3\nbar: 5\n...\n", /*Ctxt=*/nullptr, suppressErrorMessages);
    yin >> doc;
    EXPECT_TRUE(!!yin.error());
  }
}

struct OptionalTest {
  std::vector<int> Numbers;
  std::optional<int> MaybeNumber;
};

struct OptionalTestSeq {
  std::vector<OptionalTest> Tests;
};

LLVM_YAML_IS_SEQUENCE_VECTOR(OptionalTest)
namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<OptionalTest> {
    static void mapping(IO& IO, OptionalTest &OT) {
      IO.mapOptional("Numbers", OT.Numbers);
      IO.mapOptional("MaybeNumber", OT.MaybeNumber);
    }
  };

  template <>
  struct MappingTraits<OptionalTestSeq> {
    static void mapping(IO &IO, OptionalTestSeq &OTS) {
      IO.mapOptional("Tests", OTS.Tests);
    }
  };
}
}

TEST(YAMLIO, SequenceElideTest) {
  // Test that writing out a purely optional structure with its fields set to
  // default followed by other data is properly read back in.
  OptionalTestSeq Seq;
  OptionalTest One, Two, Three, Four;
  int N[] = {1, 2, 3};
  Three.Numbers.assign(N, N + 3);
  Seq.Tests.push_back(One);
  Seq.Tests.push_back(Two);
  Seq.Tests.push_back(Three);
  Seq.Tests.push_back(Four);

  std::string intermediate;
  {
    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << Seq;
  }

  Input yin(intermediate);
  OptionalTestSeq Seq2;
  yin >> Seq2;

  EXPECT_FALSE(yin.error());

  EXPECT_EQ(4UL, Seq2.Tests.size());

  EXPECT_TRUE(Seq2.Tests[0].Numbers.empty());
  EXPECT_TRUE(Seq2.Tests[1].Numbers.empty());

  EXPECT_EQ(1, Seq2.Tests[2].Numbers[0]);
  EXPECT_EQ(2, Seq2.Tests[2].Numbers[1]);
  EXPECT_EQ(3, Seq2.Tests[2].Numbers[2]);

  EXPECT_TRUE(Seq2.Tests[3].Numbers.empty());
}

TEST(YAMLIO, TestEmptyStringFailsForMapWithRequiredFields) {
  FooBar doc;
  Input yin("");
  yin >> doc;
  EXPECT_TRUE(!!yin.error());
}

TEST(YAMLIO, TestEmptyStringSucceedsForMapWithOptionalFields) {
  OptionalTest doc;
  Input yin("");
  yin >> doc;
  EXPECT_FALSE(yin.error());
  EXPECT_FALSE(doc.MaybeNumber.has_value());
}

TEST(YAMLIO, TestEmptyStringSucceedsForSequence) {
  std::vector<uint8_t> seq;
  Input yin("", /*Ctxt=*/nullptr, suppressErrorMessages);
  yin >> seq;

  EXPECT_FALSE(yin.error());
  EXPECT_TRUE(seq.empty());
}

struct FlowMap {
  llvm::StringRef str1, str2, str3;
  FlowMap(llvm::StringRef str1, llvm::StringRef str2, llvm::StringRef str3)
    : str1(str1), str2(str2), str3(str3) {}
};

struct FlowSeq {
  llvm::StringRef str;
  FlowSeq(llvm::StringRef S) : str(S) {}
  FlowSeq() = default;
};

namespace llvm {
namespace yaml {
  template <>
  struct MappingTraits<FlowMap> {
    static void mapping(IO &io, FlowMap &fm) {
      io.mapRequired("str1", fm.str1);
      io.mapRequired("str2", fm.str2);
      io.mapRequired("str3", fm.str3);
    }

    static const bool flow = true;
  };

template <>
struct ScalarTraits<FlowSeq> {
  static void output(const FlowSeq &value, void*, llvm::raw_ostream &out) {
    out << value.str;
  }
  static StringRef input(StringRef scalar, void*, FlowSeq &value) {
    value.str = scalar;
    return "";
  }

  static QuotingType mustQuote(StringRef S) { return QuotingType::None; }
};
}
}

LLVM_YAML_IS_FLOW_SEQUENCE_VECTOR(FlowSeq)

TEST(YAMLIO, TestWrapFlow) {
  std::string out;
  llvm::raw_string_ostream ostr(out);
  FlowMap Map("This is str1", "This is str2", "This is str3");
  std::vector<FlowSeq> Seq;
  Seq.emplace_back("This is str1");
  Seq.emplace_back("This is str2");
  Seq.emplace_back("This is str3");

  {
    // 20 is just bellow the total length of the first mapping field.
    // We should wreap at every element.
    Output yout(ostr, nullptr, 15);

    yout << Map;
    EXPECT_EQ(out,
              "---\n"
              "{ str1: This is str1, \n"
              "  str2: This is str2, \n"
              "  str3: This is str3 }\n"
              "...\n");
    out.clear();

    yout << Seq;
    EXPECT_EQ(out,
              "---\n"
              "[ This is str1, \n"
              "  This is str2, \n"
              "  This is str3 ]\n"
              "...\n");
    out.clear();
  }
  {
    // 25 will allow the second field to be output on the first line.
    Output yout(ostr, nullptr, 25);

    yout << Map;
    EXPECT_EQ(out,
              "---\n"
              "{ str1: This is str1, str2: This is str2, \n"
              "  str3: This is str3 }\n"
              "...\n");
    out.clear();

    yout << Seq;
    EXPECT_EQ(out,
              "---\n"
              "[ This is str1, This is str2, \n"
              "  This is str3 ]\n"
              "...\n");
    out.clear();
  }
  {
    // 0 means no wrapping.
    Output yout(ostr, nullptr, 0);

    yout << Map;
    EXPECT_EQ(out,
              "---\n"
              "{ str1: This is str1, str2: This is str2, str3: This is str3 }\n"
              "...\n");
    out.clear();

    yout << Seq;
    EXPECT_EQ(out,
              "---\n"
              "[ This is str1, This is str2, This is str3 ]\n"
              "...\n");
    out.clear();
  }
}

struct MappingContext {
  int A = 0;
};
struct SimpleMap {
  int B = 0;
  int C = 0;
};

struct NestedMap {
  NestedMap(MappingContext &Context) : Context(Context) {}
  SimpleMap Simple;
  MappingContext &Context;
};

namespace llvm {
namespace yaml {
template <> struct MappingContextTraits<SimpleMap, MappingContext> {
  static void mapping(IO &io, SimpleMap &sm, MappingContext &Context) {
    io.mapRequired("B", sm.B);
    io.mapRequired("C", sm.C);
    ++Context.A;
    io.mapRequired("Context", Context.A);
  }
  static std::string validate(IO &io, SimpleMap &sm, MappingContext &Context) {
    return "";
  }
};

template <> struct MappingTraits<NestedMap> {
  static void mapping(IO &io, NestedMap &nm) {
    io.mapRequired("Simple", nm.Simple, nm.Context);
  }
};
}
}

TEST(YAMLIO, TestMapWithContext) {
  MappingContext Context;
  NestedMap Nested(Context);
  std::string out;
  llvm::raw_string_ostream ostr(out);

  Output yout(ostr, nullptr, 15);

  yout << Nested;
  EXPECT_EQ(1, Context.A);
  EXPECT_EQ("---\n"
            "Simple:\n"
            "  B:               0\n"
            "  C:               0\n"
            "  Context:         1\n"
            "...\n",
            out);

  out.clear();

  Nested.Simple.B = 2;
  Nested.Simple.C = 3;
  yout << Nested;
  EXPECT_EQ(2, Context.A);
  EXPECT_EQ("---\n"
            "Simple:\n"
            "  B:               2\n"
            "  C:               3\n"
            "  Context:         2\n"
            "...\n",
            out);
  out.clear();
}

LLVM_YAML_IS_STRING_MAP(int)

TEST(YAMLIO, TestCustomMapping) {
  std::map<std::string, int> x;

  std::string out;
  llvm::raw_string_ostream ostr(out);
  Output xout(ostr, nullptr, 0);

  xout << x;
  EXPECT_EQ("---\n"
            "{}\n"
            "...\n",
            out);

  x["foo"] = 1;
  x["bar"] = 2;

  out.clear();
  xout << x;
  EXPECT_EQ("---\n"
            "bar:             2\n"
            "foo:             1\n"
            "...\n",
            out);

  Input yin(out);
  std::map<std::string, int> y;
  yin >> y;
  EXPECT_EQ(2ul, y.size());
  EXPECT_EQ(1, y["foo"]);
  EXPECT_EQ(2, y["bar"]);
}

LLVM_YAML_IS_STRING_MAP(FooBar)

TEST(YAMLIO, TestCustomMappingStruct) {
  std::map<std::string, FooBar> x;
  x["foo"].foo = 1;
  x["foo"].bar = 2;
  x["bar"].foo = 3;
  x["bar"].bar = 4;

  std::string out;
  llvm::raw_string_ostream ostr(out);
  Output xout(ostr, nullptr, 0);

  xout << x;
  EXPECT_EQ("---\n"
            "bar:\n"
            "  foo:             3\n"
            "  bar:             4\n"
            "foo:\n"
            "  foo:             1\n"
            "  bar:             2\n"
            "...\n",
            out);

  Input yin(out);
  std::map<std::string, FooBar> y;
  yin >> y;
  EXPECT_EQ(2ul, y.size());
  EXPECT_EQ(1, y["foo"].foo);
  EXPECT_EQ(2, y["foo"].bar);
  EXPECT_EQ(3, y["bar"].foo);
  EXPECT_EQ(4, y["bar"].bar);
}

struct FooBarMapMap {
  std::map<std::string, FooBar> fbm;
};

namespace llvm {
namespace yaml {
template <> struct MappingTraits<FooBarMapMap> {
  static void mapping(IO &io, FooBarMapMap &x) {
    io.mapRequired("fbm", x.fbm);
  }
};
}
}

TEST(YAMLIO, TestEmptyMapWrite) {
  FooBarMapMap cont;
  std::string str;
  llvm::raw_string_ostream OS(str);
  Output yout(OS);
  yout << cont;
  EXPECT_EQ(str, "---\nfbm:             {}\n...\n");
}

TEST(YAMLIO, TestEmptySequenceWrite) {
  {
    FooBarContainer cont;
    std::string str;
    llvm::raw_string_ostream OS(str);
    Output yout(OS);
    yout << cont;
    EXPECT_EQ(str, "---\nfbs:             []\n...\n");
  }

  {
    FooBarSequence seq;
    std::string str;
    llvm::raw_string_ostream OS(str);
    Output yout(OS);
    yout << seq;
    EXPECT_EQ(str, "---\n[]\n...\n");
  }
}

static void TestEscaped(llvm::StringRef Input, llvm::StringRef Expected) {
  std::string out;
  llvm::raw_string_ostream ostr(out);
  Output xout(ostr, nullptr, 0);

  llvm::yaml::EmptyContext Ctx;
  yamlize(xout, Input, true, Ctx);

  // Make a separate StringRef so we get nice byte-by-byte output.
  llvm::StringRef Got(out);
  EXPECT_EQ(Expected, Got);
}

TEST(YAMLIO, TestEscaped) {
  // Single quote
  TestEscaped("@abc@", "'@abc@'");
  // No quote
  TestEscaped("abc", "abc");
  // Forward slash quoted
  TestEscaped("abc/", "'abc/'");
  // Double quote non-printable
  TestEscaped("\01@abc@", "\"\\x01@abc@\"");
  // Double quote inside single quote
  TestEscaped("abc\"fdf", "'abc\"fdf'");
  // Double quote inside double quote
  TestEscaped("\01bc\"fdf", "\"\\x01bc\\\"fdf\"");
  // Single quote inside single quote
  TestEscaped("abc'fdf", "'abc''fdf'");
  // UTF8
  TestEscaped("/*параметр*/", "\"/*параметр*/\"");
  // UTF8 with single quote inside double quote
  TestEscaped("parameter 'параметр' is unused",
              "\"parameter 'параметр' is unused\"");

  // String with embedded non-printable multibyte UTF-8 sequence (U+200B
  // zero-width space). The thing to test here is that we emit a
  // unicode-scalar level escape like \uNNNN (at the YAML level), and don't
  // just pass the UTF-8 byte sequence through as with quoted printables.
  {
    const unsigned char foobar[10] = {'f', 'o', 'o',
                                      0xE2, 0x80, 0x8B, // UTF-8 of U+200B
                                      'b', 'a', 'r',
                                      0x0};
    TestEscaped((char const *)foobar, "\"foo\\u200Bbar\"");
  }
}

TEST(YAMLIO, Numeric) {
  EXPECT_TRUE(isNumeric(".inf"));
  EXPECT_TRUE(isNumeric(".INF"));
  EXPECT_TRUE(isNumeric(".Inf"));
  EXPECT_TRUE(isNumeric("-.inf"));
  EXPECT_TRUE(isNumeric("+.inf"));

  EXPECT_TRUE(isNumeric(".nan"));
  EXPECT_TRUE(isNumeric(".NaN"));
  EXPECT_TRUE(isNumeric(".NAN"));

  EXPECT_TRUE(isNumeric("0"));
  EXPECT_TRUE(isNumeric("0."));
  EXPECT_TRUE(isNumeric("0.0"));
  EXPECT_TRUE(isNumeric("-0.0"));
  EXPECT_TRUE(isNumeric("+0.0"));

  EXPECT_TRUE(isNumeric("12345"));
  EXPECT_TRUE(isNumeric("012345"));
  EXPECT_TRUE(isNumeric("+12.0"));
  EXPECT_TRUE(isNumeric(".5"));
  EXPECT_TRUE(isNumeric("+.5"));
  EXPECT_TRUE(isNumeric("-1.0"));

  EXPECT_TRUE(isNumeric("2.3e4"));
  EXPECT_TRUE(isNumeric("-2E+05"));
  EXPECT_TRUE(isNumeric("+12e03"));
  EXPECT_TRUE(isNumeric("6.8523015e+5"));

  EXPECT_TRUE(isNumeric("1.e+1"));
  EXPECT_TRUE(isNumeric(".0e+1"));

  EXPECT_TRUE(isNumeric("0x2aF3"));
  EXPECT_TRUE(isNumeric("0o01234567"));

  EXPECT_FALSE(isNumeric("not a number"));
  EXPECT_FALSE(isNumeric("."));
  EXPECT_FALSE(isNumeric(".e+1"));
  EXPECT_FALSE(isNumeric(".1e"));
  EXPECT_FALSE(isNumeric(".1e+"));
  EXPECT_FALSE(isNumeric(".1e++1"));

  EXPECT_FALSE(isNumeric("ABCD"));
  EXPECT_FALSE(isNumeric("+0x2AF3"));
  EXPECT_FALSE(isNumeric("-0x2AF3"));
  EXPECT_FALSE(isNumeric("0x2AF3Z"));
  EXPECT_FALSE(isNumeric("0o012345678"));
  EXPECT_FALSE(isNumeric("0xZ"));
  EXPECT_FALSE(isNumeric("-0o012345678"));
  EXPECT_FALSE(isNumeric("000003A8229434B839616A25C16B0291F77A438B"));

  EXPECT_FALSE(isNumeric(""));
  EXPECT_FALSE(isNumeric("."));
  EXPECT_FALSE(isNumeric(".e+1"));
  EXPECT_FALSE(isNumeric(".e+"));
  EXPECT_FALSE(isNumeric(".e"));
  EXPECT_FALSE(isNumeric("e1"));

  // Deprecated formats: as for YAML 1.2 specification, the following are not
  // valid numbers anymore:
  //
  // * Sexagecimal numbers
  // * Decimal numbers with comma s the delimiter
  // * "inf", "nan" without '.' prefix
  EXPECT_FALSE(isNumeric("3:25:45"));
  EXPECT_FALSE(isNumeric("+12,345"));
  EXPECT_FALSE(isNumeric("-inf"));
  EXPECT_FALSE(isNumeric("1,230.15"));
}

//===----------------------------------------------------------------------===//
//  Test writing and reading escaped keys
//===----------------------------------------------------------------------===//

// Struct with dynamic string key
struct QuotedKeyStruct {
  int unquoted_bool;
  int unquoted_null;
  int unquoted_numeric;
  int unquoted_str;
  int colon;
  int just_space;
  int unprintable;
};

namespace llvm {
namespace yaml {
template <> struct MappingTraits<QuotedKeyStruct> {
  static void mapping(IO &io, QuotedKeyStruct &map) {
    io.mapRequired("true", map.unquoted_bool);
    io.mapRequired("null", map.unquoted_null);
    io.mapRequired("42", map.unquoted_numeric);
    io.mapRequired("unquoted", map.unquoted_str);
    io.mapRequired(":", map.colon);
    io.mapRequired(" ", map.just_space);
    char unprintableKey[] = {/* \f, form-feed */ 0xC, 0};
    io.mapRequired(unprintableKey, map.unprintable);
  }
};
} // namespace yaml
} // namespace llvm

TEST(YAMLIO, TestQuotedKeyRead) {
  QuotedKeyStruct map = {};
  Input yin("---\ntrue:  1\nnull:  2\n42:  3\nunquoted:  4\n':':  5\n' ':  "
            "6\n\"\\f\":  7\n...\n");
  yin >> map;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(map.unquoted_bool, 1);
  EXPECT_EQ(map.unquoted_null, 2);
  EXPECT_EQ(map.unquoted_numeric, 3);
  EXPECT_EQ(map.unquoted_str, 4);
  EXPECT_EQ(map.colon, 5);
  EXPECT_EQ(map.just_space, 6);
  EXPECT_EQ(map.unprintable, 7);
}

TEST(YAMLIO, TestQuotedKeyWriteRead) {
  std::string intermediate;
  {
    QuotedKeyStruct map = {1, 2, 3, 4, 5, 6, 7};
    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << map;
  }

  EXPECT_NE(std::string::npos, intermediate.find("true:"));
  EXPECT_NE(std::string::npos, intermediate.find("null:"));
  EXPECT_NE(std::string::npos, intermediate.find("42:"));
  EXPECT_NE(std::string::npos, intermediate.find("unquoted:"));
  EXPECT_NE(std::string::npos, intermediate.find("':':"));
  EXPECT_NE(std::string::npos, intermediate.find("' '"));
  EXPECT_NE(std::string::npos, intermediate.find("\"\\f\":"));

  {
    Input yin(intermediate);
    QuotedKeyStruct map;
    yin >> map;

    EXPECT_FALSE(yin.error());
    EXPECT_EQ(map.unquoted_bool, 1);
    EXPECT_EQ(map.unquoted_null, 2);
    EXPECT_EQ(map.unquoted_numeric, 3);
    EXPECT_EQ(map.unquoted_str, 4);
    EXPECT_EQ(map.colon, 5);
    EXPECT_EQ(map.just_space, 6);
    EXPECT_EQ(map.unprintable, 7);
  }
}

//===----------------------------------------------------------------------===//
//  Test PolymorphicTraits and TaggedScalarTraits
//===----------------------------------------------------------------------===//

struct Poly {
  enum NodeKind {
    NK_Scalar,
    NK_Seq,
    NK_Map,
  } Kind;

  Poly(NodeKind Kind) : Kind(Kind) {}

  virtual ~Poly() = default;

  NodeKind getKind() const { return Kind; }
};

struct Scalar : Poly {
  enum ScalarKind {
    SK_Unknown,
    SK_Double,
    SK_Bool,
  } SKind;

  union {
    double DoubleValue;
    bool BoolValue;
  };

  Scalar() : Poly(NK_Scalar), SKind(SK_Unknown) {}
  Scalar(double DoubleValue)
      : Poly(NK_Scalar), SKind(SK_Double), DoubleValue(DoubleValue) {}
  Scalar(bool BoolValue)
      : Poly(NK_Scalar), SKind(SK_Bool), BoolValue(BoolValue) {}

  static bool classof(const Poly *N) { return N->getKind() == NK_Scalar; }
};

struct Seq : Poly, std::vector<std::unique_ptr<Poly>> {
  Seq() : Poly(NK_Seq) {}

  static bool classof(const Poly *N) { return N->getKind() == NK_Seq; }
};

struct Map : Poly, llvm::StringMap<std::unique_ptr<Poly>> {
  Map() : Poly(NK_Map) {}

  static bool classof(const Poly *N) { return N->getKind() == NK_Map; }
};

namespace llvm {
namespace yaml {

template <> struct PolymorphicTraits<std::unique_ptr<Poly>> {
  static NodeKind getKind(const std::unique_ptr<Poly> &N) {
    if (isa<Scalar>(*N))
      return NodeKind::Scalar;
    if (isa<Seq>(*N))
      return NodeKind::Sequence;
    if (isa<Map>(*N))
      return NodeKind::Map;
    llvm_unreachable("unsupported node type");
  }

  static Scalar &getAsScalar(std::unique_ptr<Poly> &N) {
    if (!N || !isa<Scalar>(*N))
      N = std::make_unique<Scalar>();
    return *cast<Scalar>(N.get());
  }

  static Seq &getAsSequence(std::unique_ptr<Poly> &N) {
    if (!N || !isa<Seq>(*N))
      N = std::make_unique<Seq>();
    return *cast<Seq>(N.get());
  }

  static Map &getAsMap(std::unique_ptr<Poly> &N) {
    if (!N || !isa<Map>(*N))
      N = std::make_unique<Map>();
    return *cast<Map>(N.get());
  }
};

template <> struct TaggedScalarTraits<Scalar> {
  static void output(const Scalar &S, void *Ctxt, raw_ostream &ScalarOS,
                     raw_ostream &TagOS) {
    switch (S.SKind) {
    case Scalar::SK_Unknown:
      report_fatal_error("output unknown scalar");
      break;
    case Scalar::SK_Double:
      TagOS << "!double";
      ScalarTraits<double>::output(S.DoubleValue, Ctxt, ScalarOS);
      break;
    case Scalar::SK_Bool:
      TagOS << "!bool";
      ScalarTraits<bool>::output(S.BoolValue, Ctxt, ScalarOS);
      break;
    }
  }

  static StringRef input(StringRef ScalarStr, StringRef Tag, void *Ctxt,
                         Scalar &S) {
    S.SKind = StringSwitch<Scalar::ScalarKind>(Tag)
                  .Case("!double", Scalar::SK_Double)
                  .Case("!bool", Scalar::SK_Bool)
                  .Default(Scalar::SK_Unknown);
    switch (S.SKind) {
    case Scalar::SK_Unknown:
      return StringRef("unknown scalar tag");
    case Scalar::SK_Double:
      return ScalarTraits<double>::input(ScalarStr, Ctxt, S.DoubleValue);
    case Scalar::SK_Bool:
      return ScalarTraits<bool>::input(ScalarStr, Ctxt, S.BoolValue);
    }
    llvm_unreachable("unknown scalar kind");
  }

  static QuotingType mustQuote(const Scalar &S, StringRef Str) {
    switch (S.SKind) {
    case Scalar::SK_Unknown:
      report_fatal_error("quote unknown scalar");
    case Scalar::SK_Double:
      return ScalarTraits<double>::mustQuote(Str);
    case Scalar::SK_Bool:
      return ScalarTraits<bool>::mustQuote(Str);
    }
    llvm_unreachable("unknown scalar kind");
  }
};

template <> struct CustomMappingTraits<Map> {
  static void inputOne(IO &IO, StringRef Key, Map &M) {
    IO.mapRequired(Key.str().c_str(), M[Key]);
  }

  static void output(IO &IO, Map &M) {
    for (auto &N : M)
      IO.mapRequired(N.getKey().str().c_str(), N.getValue());
  }
};

template <> struct SequenceTraits<Seq> {
  static size_t size(IO &IO, Seq &A) { return A.size(); }

  static std::unique_ptr<Poly> &element(IO &IO, Seq &A, size_t Index) {
    if (Index >= A.size())
      A.resize(Index + 1);
    return A[Index];
  }
};

} // namespace yaml
} // namespace llvm

TEST(YAMLIO, TestReadWritePolymorphicScalar) {
  std::string intermediate;
  std::unique_ptr<Poly> node = std::make_unique<Scalar>(true);

  llvm::raw_string_ostream ostr(intermediate);
  Output yout(ostr);
#ifdef GTEST_HAS_DEATH_TEST
#ifndef NDEBUG
  EXPECT_DEATH(yout << node, "plain scalar documents are not supported");
#endif
#endif
}

TEST(YAMLIO, TestReadWritePolymorphicSeq) {
  std::string intermediate;
  {
    auto seq = std::make_unique<Seq>();
    seq->push_back(std::make_unique<Scalar>(true));
    seq->push_back(std::make_unique<Scalar>(1.0));
    auto node = llvm::unique_dyn_cast<Poly>(seq);

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << node;
  }
  {
    Input yin(intermediate);
    std::unique_ptr<Poly> node;
    yin >> node;

    EXPECT_FALSE(yin.error());
    auto seq = llvm::dyn_cast<Seq>(node.get());
    ASSERT_TRUE(seq);
    ASSERT_EQ(seq->size(), 2u);
    auto first = llvm::dyn_cast<Scalar>((*seq)[0].get());
    ASSERT_TRUE(first);
    EXPECT_EQ(first->SKind, Scalar::SK_Bool);
    EXPECT_TRUE(first->BoolValue);
    auto second = llvm::dyn_cast<Scalar>((*seq)[1].get());
    ASSERT_TRUE(second);
    EXPECT_EQ(second->SKind, Scalar::SK_Double);
    EXPECT_EQ(second->DoubleValue, 1.0);
  }
}

TEST(YAMLIO, TestReadWritePolymorphicMap) {
  std::string intermediate;
  {
    auto map = std::make_unique<Map>();
    (*map)["foo"] = std::make_unique<Scalar>(false);
    (*map)["bar"] = std::make_unique<Scalar>(2.0);
    std::unique_ptr<Poly> node = llvm::unique_dyn_cast<Poly>(map);

    llvm::raw_string_ostream ostr(intermediate);
    Output yout(ostr);
    yout << node;
  }
  {
    Input yin(intermediate);
    std::unique_ptr<Poly> node;
    yin >> node;

    EXPECT_FALSE(yin.error());
    auto map = llvm::dyn_cast<Map>(node.get());
    ASSERT_TRUE(map);
    auto foo = llvm::dyn_cast<Scalar>((*map)["foo"].get());
    ASSERT_TRUE(foo);
    EXPECT_EQ(foo->SKind, Scalar::SK_Bool);
    EXPECT_FALSE(foo->BoolValue);
    auto bar = llvm::dyn_cast<Scalar>((*map)["bar"].get());
    ASSERT_TRUE(bar);
    EXPECT_EQ(bar->SKind, Scalar::SK_Double);
    EXPECT_EQ(bar->DoubleValue, 2.0);
  }
}

TEST(YAMLIO, TestAnchorMapError) {
  Input yin("& & &: ");
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestFlowSequenceTokenErrors) {
  Input yin(",");
  EXPECT_FALSE(yin.setCurrentDocument());
  EXPECT_TRUE(yin.error());

  Input yin2("]");
  EXPECT_FALSE(yin2.setCurrentDocument());
  EXPECT_TRUE(yin2.error());

  Input yin3("}");
  EXPECT_FALSE(yin3.setCurrentDocument());
  EXPECT_TRUE(yin3.error());
}

TEST(YAMLIO, TestDirectiveMappingNoValue) {
  Input yin("%YAML\n{5:");
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());

  Input yin2("%TAG\n'\x98!< :\n");
  yin2.setCurrentDocument();
  EXPECT_TRUE(yin2.error());
}

TEST(YAMLIO, TestUnescapeInfiniteLoop) {
  Input yin("\"\\u\\^#\\\\\"");
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestScannerUnexpectedCharacter) {
  Input yin("!<$\x9F.");
  EXPECT_FALSE(yin.setCurrentDocument());
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestUnknownDirective) {
  Input yin("%");
  EXPECT_FALSE(yin.setCurrentDocument());
  EXPECT_TRUE(yin.error());

  Input yin2("%)");
  EXPECT_FALSE(yin2.setCurrentDocument());
  EXPECT_TRUE(yin2.error());
}

TEST(YAMLIO, TestEmptyAlias) {
  Input yin("&");
  EXPECT_FALSE(yin.setCurrentDocument());
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestEmptyAnchor) {
  Input yin("*");
  EXPECT_FALSE(yin.setCurrentDocument());
}

TEST(YAMLIO, TestScannerNoNullEmpty) {
  std::vector<char> str{};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_FALSE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullSequenceOfNull) {
  std::vector<char> str{'-'};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_FALSE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullSimpleSequence) {
  std::vector<char> str{'-', ' ', 'a'};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_FALSE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullUnbalancedMap) {
  std::vector<char> str{'{'};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullEmptyMap) {
  std::vector<char> str{'{', '}'};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_FALSE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullUnbalancedSequence) {
  std::vector<char> str{'['};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullEmptySequence) {
  std::vector<char> str{'[', ']'};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_FALSE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullScalarUnbalancedDoubleQuote) {
  std::vector<char> str{'"'};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullScalarUnbalancedSingleQuote) {
  std::vector<char> str{'\''};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullEmptyAlias) {
  std::vector<char> str{'&'};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullEmptyAnchor) {
  std::vector<char> str{'*'};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullDecodeInvalidUTF8) {
  std::vector<char> str{'\xef'};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());
}

TEST(YAMLIO, TestScannerNoNullScanPlainScalarInFlow) {
  std::vector<char> str{'{', 'a', ':'};
  Input yin(llvm::StringRef(str.data(), str.size()));
  yin.setCurrentDocument();
  EXPECT_TRUE(yin.error());
}

struct FixedArray {
  FixedArray() {
    // Initialize to int max as a sentinel value.
    for (auto &v : values)
      v = std::numeric_limits<int>::max();
  }
  int values[4];
};

struct StdArray {
  StdArray() {
    // Initialize to int max as a sentinel value.
    for (auto &v : values)
      v = std::numeric_limits<int>::max();
  }
  std::array<int, 4> values;
};

namespace llvm {
namespace yaml {
template <> struct MappingTraits<FixedArray> {
  static void mapping(IO &io, FixedArray &st) {
    MutableArrayRef<int> array = st.values;
    io.mapRequired("Values", array);
  }
};
template <> struct MappingTraits<StdArray> {
  static void mapping(IO &io, StdArray &st) {
    io.mapRequired("Values", st.values);
  }
};
} // namespace yaml
} // namespace llvm

using TestTypes = ::testing::Types<FixedArray, StdArray>;

template <typename T> class YAMLIO : public testing::Test {};
TYPED_TEST_SUITE(YAMLIO, TestTypes, );

TYPED_TEST(YAMLIO, FixedSizeArray) {
  TypeParam faval;
  Input yin("---\nValues:  [ 1, 2, 3, 4 ]\n...\n");
  yin >> faval;

  EXPECT_FALSE(yin.error());
  EXPECT_EQ(faval.values[0], 1);
  EXPECT_EQ(faval.values[1], 2);
  EXPECT_EQ(faval.values[2], 3);
  EXPECT_EQ(faval.values[3], 4);

  std::string serialized;
  {
    llvm::raw_string_ostream os(serialized);
    Output yout(os);
    yout << faval;
  }
  auto expected = "---\n"
                  "Values:          [ 1, 2, 3, 4 ]\n"
                  "...\n";
  ASSERT_EQ(serialized, expected);
}

TYPED_TEST(YAMLIO, FixedSizeArrayMismatch) {
  {
    TypeParam faval;
    Input yin("---\nValues:  [ 1, 2, 3 ]\n...\n");
    yin >> faval;

    // No error for too small, leaves the default initialized value
    EXPECT_FALSE(yin.error());
    EXPECT_EQ(faval.values[0], 1);
    EXPECT_EQ(faval.values[1], 2);
    EXPECT_EQ(faval.values[2], 3);
    EXPECT_EQ(faval.values[3], std::numeric_limits<int>::max());
  }

  {
    TypeParam faval;
    Input yin("---\nValues:  [ 1, 2, 3, 4, 5 ]\n...\n");
    yin >> faval;

    // Error for too many elements.
    EXPECT_TRUE(!!yin.error());
  }
}