//===- llvm/unittest/ADT/StringRefTest.cpp - StringRef unit tests ---------===//
//
// 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/StringRef.h"
#include "llvm/ADT/Hashing.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/raw_ostream.h"
#include "gtest/gtest.h"
using namespace llvm;

namespace llvm {

std::ostream &operator<<(std::ostream &OS, const StringRef &S) {
  OS << S.str();
  return OS;
}

std::ostream &operator<<(std::ostream &OS,
                         const std::pair<StringRef, StringRef> &P) {
  OS << "(" << P.first << ", " << P.second << ")";
  return OS;
}

}

// Check that we can't accidentally assign a temporary std::string to a
// StringRef. (Unfortunately we can't make use of the same thing with
// constructors.)
//
// Disable this check under MSVC; even MSVC 2015 isn't consistent between
// std::is_assignable and actually writing such an assignment.
#if !defined(_MSC_VER)
static_assert(
    !std::is_assignable<StringRef&, std::string>::value,
    "Assigning from prvalue std::string");
static_assert(
    !std::is_assignable<StringRef&, std::string &&>::value,
    "Assigning from xvalue std::string");
static_assert(
    std::is_assignable<StringRef&, std::string &>::value,
    "Assigning from lvalue std::string");
static_assert(
    std::is_assignable<StringRef&, const char *>::value,
    "Assigning from prvalue C string");
static_assert(
    std::is_assignable<StringRef&, const char * &&>::value,
    "Assigning from xvalue C string");
static_assert(
    std::is_assignable<StringRef&, const char * &>::value,
    "Assigning from lvalue C string");
#endif


namespace {
TEST(StringRefTest, Construction) {
  EXPECT_EQ("", StringRef());
  EXPECT_EQ("hello", StringRef("hello"));
  EXPECT_EQ("hello", StringRef("hello world", 5));
  EXPECT_EQ("hello", StringRef(std::string("hello")));
}

TEST(StringRefTest, EmptyInitializerList) {
  StringRef S = {};
  EXPECT_TRUE(S.empty());

  S = {};
  EXPECT_TRUE(S.empty());
}

TEST(StringRefTest, Iteration) {
  StringRef S("hello");
  const char *p = "hello";
  for (const char *it = S.begin(), *ie = S.end(); it != ie; ++it, ++p)
    EXPECT_EQ(*it, *p);
}

TEST(StringRefTest, StringOps) {
  const char *p = "hello";
  EXPECT_EQ(p, StringRef(p, 0).data());
  EXPECT_TRUE(StringRef().empty());
  EXPECT_EQ((size_t) 5, StringRef("hello").size());
  EXPECT_EQ(-1, StringRef("aab").compare("aad"));
  EXPECT_EQ( 0, StringRef("aab").compare("aab"));
  EXPECT_EQ( 1, StringRef("aab").compare("aaa"));
  EXPECT_EQ(-1, StringRef("aab").compare("aabb"));
  EXPECT_EQ( 1, StringRef("aab").compare("aa"));
  EXPECT_EQ( 1, StringRef("\xFF").compare("\1"));

  EXPECT_EQ(-1, StringRef("AaB").compare_lower("aAd"));
  EXPECT_EQ( 0, StringRef("AaB").compare_lower("aab"));
  EXPECT_EQ( 1, StringRef("AaB").compare_lower("AAA"));
  EXPECT_EQ(-1, StringRef("AaB").compare_lower("aaBb"));
  EXPECT_EQ(-1, StringRef("AaB").compare_lower("bb"));
  EXPECT_EQ( 1, StringRef("aaBb").compare_lower("AaB"));
  EXPECT_EQ( 1, StringRef("bb").compare_lower("AaB"));
  EXPECT_EQ( 1, StringRef("AaB").compare_lower("aA"));
  EXPECT_EQ( 1, StringRef("\xFF").compare_lower("\1"));

  EXPECT_EQ(-1, StringRef("aab").compare_numeric("aad"));
  EXPECT_EQ( 0, StringRef("aab").compare_numeric("aab"));
  EXPECT_EQ( 1, StringRef("aab").compare_numeric("aaa"));
  EXPECT_EQ(-1, StringRef("aab").compare_numeric("aabb"));
  EXPECT_EQ( 1, StringRef("aab").compare_numeric("aa"));
  EXPECT_EQ(-1, StringRef("1").compare_numeric("10"));
  EXPECT_EQ( 0, StringRef("10").compare_numeric("10"));
  EXPECT_EQ( 0, StringRef("10a").compare_numeric("10a"));
  EXPECT_EQ( 1, StringRef("2").compare_numeric("1"));
  EXPECT_EQ( 0, StringRef("llvm_v1i64_ty").compare_numeric("llvm_v1i64_ty"));
  EXPECT_EQ( 1, StringRef("\xFF").compare_numeric("\1"));
  EXPECT_EQ( 1, StringRef("V16").compare_numeric("V1_q0"));
  EXPECT_EQ(-1, StringRef("V1_q0").compare_numeric("V16"));
  EXPECT_EQ(-1, StringRef("V8_q0").compare_numeric("V16"));
  EXPECT_EQ( 1, StringRef("V16").compare_numeric("V8_q0"));
  EXPECT_EQ(-1, StringRef("V1_q0").compare_numeric("V8_q0"));
  EXPECT_EQ( 1, StringRef("V8_q0").compare_numeric("V1_q0"));
}

TEST(StringRefTest, Operators) {
  EXPECT_EQ("", StringRef());
  EXPECT_TRUE(StringRef("aab") < StringRef("aad"));
  EXPECT_FALSE(StringRef("aab") < StringRef("aab"));
  EXPECT_TRUE(StringRef("aab") <= StringRef("aab"));
  EXPECT_FALSE(StringRef("aab") <= StringRef("aaa"));
  EXPECT_TRUE(StringRef("aad") > StringRef("aab"));
  EXPECT_FALSE(StringRef("aab") > StringRef("aab"));
  EXPECT_TRUE(StringRef("aab") >= StringRef("aab"));
  EXPECT_FALSE(StringRef("aaa") >= StringRef("aab"));
  EXPECT_EQ(StringRef("aab"), StringRef("aab"));
  EXPECT_FALSE(StringRef("aab") == StringRef("aac"));
  EXPECT_FALSE(StringRef("aab") != StringRef("aab"));
  EXPECT_TRUE(StringRef("aab") != StringRef("aac"));
  EXPECT_EQ('a', StringRef("aab")[1]);
}

TEST(StringRefTest, Substr) {
  StringRef Str("hello");
  EXPECT_EQ("lo", Str.substr(3));
  EXPECT_EQ("", Str.substr(100));
  EXPECT_EQ("hello", Str.substr(0, 100));
  EXPECT_EQ("o", Str.substr(4, 10));
}

TEST(StringRefTest, Slice) {
  StringRef Str("hello");
  EXPECT_EQ("l", Str.slice(2, 3));
  EXPECT_EQ("ell", Str.slice(1, 4));
  EXPECT_EQ("llo", Str.slice(2, 100));
  EXPECT_EQ("", Str.slice(2, 1));
  EXPECT_EQ("", Str.slice(10, 20));
}

TEST(StringRefTest, Split) {
  StringRef Str("hello");
  EXPECT_EQ(std::make_pair(StringRef("hello"), StringRef("")),
            Str.split('X'));
  EXPECT_EQ(std::make_pair(StringRef("h"), StringRef("llo")),
            Str.split('e'));
  EXPECT_EQ(std::make_pair(StringRef(""), StringRef("ello")),
            Str.split('h'));
  EXPECT_EQ(std::make_pair(StringRef("he"), StringRef("lo")),
            Str.split('l'));
  EXPECT_EQ(std::make_pair(StringRef("hell"), StringRef("")),
            Str.split('o'));

  EXPECT_EQ(std::make_pair(StringRef("hello"), StringRef("")),
            Str.rsplit('X'));
  EXPECT_EQ(std::make_pair(StringRef("h"), StringRef("llo")),
            Str.rsplit('e'));
  EXPECT_EQ(std::make_pair(StringRef(""), StringRef("ello")),
            Str.rsplit('h'));
  EXPECT_EQ(std::make_pair(StringRef("hel"), StringRef("o")),
            Str.rsplit('l'));
  EXPECT_EQ(std::make_pair(StringRef("hell"), StringRef("")),
            Str.rsplit('o'));

  EXPECT_EQ(std::make_pair(StringRef("he"), StringRef("o")),
		    Str.rsplit("ll"));
  EXPECT_EQ(std::make_pair(StringRef(""), StringRef("ello")),
		    Str.rsplit("h"));
  EXPECT_EQ(std::make_pair(StringRef("hell"), StringRef("")),
	      Str.rsplit("o"));
  EXPECT_EQ(std::make_pair(StringRef("hello"), StringRef("")),
		    Str.rsplit("::"));
  EXPECT_EQ(std::make_pair(StringRef("hel"), StringRef("o")),
		    Str.rsplit("l"));
}

TEST(StringRefTest, Split2) {
  SmallVector<StringRef, 5> parts;
  SmallVector<StringRef, 5> expected;

  expected.push_back("ab"); expected.push_back("c");
  StringRef(",ab,,c,").split(parts, ",", -1, false);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back(""); expected.push_back("ab"); expected.push_back("");
  expected.push_back("c"); expected.push_back("");
  StringRef(",ab,,c,").split(parts, ",", -1, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("");
  StringRef("").split(parts, ",", -1, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  StringRef("").split(parts, ",", -1, false);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  StringRef(",").split(parts, ",", -1, false);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back(""); expected.push_back("");
  StringRef(",").split(parts, ",", -1, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a"); expected.push_back("b");
  StringRef("a,b").split(parts, ",", -1, true);
  EXPECT_TRUE(parts == expected);

  // Test MaxSplit
  expected.clear(); parts.clear();
  expected.push_back("a,,b,c");
  StringRef("a,,b,c").split(parts, ",", 0, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a,,b,c");
  StringRef("a,,b,c").split(parts, ",", 0, false);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a"); expected.push_back(",b,c");
  StringRef("a,,b,c").split(parts, ",", 1, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a"); expected.push_back(",b,c");
  StringRef("a,,b,c").split(parts, ",", 1, false);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a"); expected.push_back(""); expected.push_back("b,c");
  StringRef("a,,b,c").split(parts, ",", 2, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a"); expected.push_back("b,c");
  StringRef("a,,b,c").split(parts, ",", 2, false);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a"); expected.push_back(""); expected.push_back("b");
  expected.push_back("c");
  StringRef("a,,b,c").split(parts, ",", 3, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a"); expected.push_back("b"); expected.push_back("c");
  StringRef("a,,b,c").split(parts, ",", 3, false);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a"); expected.push_back("b"); expected.push_back("c");
  StringRef("a,,b,c").split(parts, ',', 3, false);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("");
  StringRef().split(parts, ",", 0, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back(StringRef());
  StringRef("").split(parts, ",", 0, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  StringRef("").split(parts, ",", 0, false);
  EXPECT_TRUE(parts == expected);
  StringRef().split(parts, ",", 0, false);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a");
  expected.push_back("");
  expected.push_back("b");
  expected.push_back("c,d");
  StringRef("a,,b,c,d").split(parts, ",", 3, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("");
  StringRef().split(parts, ',', 0, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back(StringRef());
  StringRef("").split(parts, ',', 0, true);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  StringRef("").split(parts, ',', 0, false);
  EXPECT_TRUE(parts == expected);
  StringRef().split(parts, ',', 0, false);
  EXPECT_TRUE(parts == expected);

  expected.clear(); parts.clear();
  expected.push_back("a");
  expected.push_back("");
  expected.push_back("b");
  expected.push_back("c,d");
  StringRef("a,,b,c,d").split(parts, ',', 3, true);
  EXPECT_TRUE(parts == expected);
}

TEST(StringRefTest, Trim) {
  StringRef Str0("hello");
  StringRef Str1(" hello ");
  StringRef Str2("  hello  ");

  EXPECT_EQ(StringRef("hello"), Str0.rtrim());
  EXPECT_EQ(StringRef(" hello"), Str1.rtrim());
  EXPECT_EQ(StringRef("  hello"), Str2.rtrim());
  EXPECT_EQ(StringRef("hello"), Str0.ltrim());
  EXPECT_EQ(StringRef("hello "), Str1.ltrim());
  EXPECT_EQ(StringRef("hello  "), Str2.ltrim());
  EXPECT_EQ(StringRef("hello"), Str0.trim());
  EXPECT_EQ(StringRef("hello"), Str1.trim());
  EXPECT_EQ(StringRef("hello"), Str2.trim());

  EXPECT_EQ(StringRef("ello"), Str0.trim("hhhhhhhhhhh"));

  EXPECT_EQ(StringRef(""), StringRef("").trim());
  EXPECT_EQ(StringRef(""), StringRef(" ").trim());
  EXPECT_EQ(StringRef("\0", 1), StringRef(" \0 ", 3).trim());
  EXPECT_EQ(StringRef("\0\0", 2), StringRef("\0\0", 2).trim());
  EXPECT_EQ(StringRef("x"), StringRef("\0\0x\0\0", 5).trim('\0'));
}

TEST(StringRefTest, StartsWith) {
  StringRef Str("hello");
  EXPECT_TRUE(Str.startswith(""));
  EXPECT_TRUE(Str.startswith("he"));
  EXPECT_FALSE(Str.startswith("helloworld"));
  EXPECT_FALSE(Str.startswith("hi"));
}

TEST(StringRefTest, StartsWithLower) {
  StringRef Str("heLLo");
  EXPECT_TRUE(Str.startswith_lower(""));
  EXPECT_TRUE(Str.startswith_lower("he"));
  EXPECT_TRUE(Str.startswith_lower("hell"));
  EXPECT_TRUE(Str.startswith_lower("HELlo"));
  EXPECT_FALSE(Str.startswith_lower("helloworld"));
  EXPECT_FALSE(Str.startswith_lower("hi"));
}

TEST(StringRefTest, ConsumeFront) {
  StringRef Str("hello");
  EXPECT_TRUE(Str.consume_front(""));
  EXPECT_EQ("hello", Str);
  EXPECT_TRUE(Str.consume_front("he"));
  EXPECT_EQ("llo", Str);
  EXPECT_FALSE(Str.consume_front("lloworld"));
  EXPECT_EQ("llo", Str);
  EXPECT_FALSE(Str.consume_front("lol"));
  EXPECT_EQ("llo", Str);
  EXPECT_TRUE(Str.consume_front("llo"));
  EXPECT_EQ("", Str);
  EXPECT_FALSE(Str.consume_front("o"));
  EXPECT_TRUE(Str.consume_front(""));
}

TEST(StringRefTest, EndsWith) {
  StringRef Str("hello");
  EXPECT_TRUE(Str.endswith(""));
  EXPECT_TRUE(Str.endswith("lo"));
  EXPECT_FALSE(Str.endswith("helloworld"));
  EXPECT_FALSE(Str.endswith("worldhello"));
  EXPECT_FALSE(Str.endswith("so"));
}

TEST(StringRefTest, EndsWithLower) {
  StringRef Str("heLLo");
  EXPECT_TRUE(Str.endswith_lower(""));
  EXPECT_TRUE(Str.endswith_lower("lo"));
  EXPECT_TRUE(Str.endswith_lower("LO"));
  EXPECT_TRUE(Str.endswith_lower("ELlo"));
  EXPECT_FALSE(Str.endswith_lower("helloworld"));
  EXPECT_FALSE(Str.endswith_lower("hi"));
}

TEST(StringRefTest, ConsumeBack) {
  StringRef Str("hello");
  EXPECT_TRUE(Str.consume_back(""));
  EXPECT_EQ("hello", Str);
  EXPECT_TRUE(Str.consume_back("lo"));
  EXPECT_EQ("hel", Str);
  EXPECT_FALSE(Str.consume_back("helhel"));
  EXPECT_EQ("hel", Str);
  EXPECT_FALSE(Str.consume_back("hle"));
  EXPECT_EQ("hel", Str);
  EXPECT_TRUE(Str.consume_back("hel"));
  EXPECT_EQ("", Str);
  EXPECT_FALSE(Str.consume_back("h"));
  EXPECT_TRUE(Str.consume_back(""));
}

TEST(StringRefTest, Find) {
  StringRef Str("helloHELLO");
  StringRef LongStr("hellx xello hell ello world foo bar hello HELLO");

  struct {
    StringRef Str;
    char C;
    std::size_t From;
    std::size_t Pos;
    std::size_t LowerPos;
  } CharExpectations[] = {
      {Str, 'h', 0U, 0U, 0U},
      {Str, 'e', 0U, 1U, 1U},
      {Str, 'l', 0U, 2U, 2U},
      {Str, 'l', 3U, 3U, 3U},
      {Str, 'o', 0U, 4U, 4U},
      {Str, 'L', 0U, 7U, 2U},
      {Str, 'z', 0U, StringRef::npos, StringRef::npos},
  };

  struct {
    StringRef Str;
    llvm::StringRef S;
    std::size_t From;
    std::size_t Pos;
    std::size_t LowerPos;
  } StrExpectations[] = {
      {Str, "helloword", 0, StringRef::npos, StringRef::npos},
      {Str, "hello", 0, 0U, 0U},
      {Str, "ello", 0, 1U, 1U},
      {Str, "zz", 0, StringRef::npos, StringRef::npos},
      {Str, "ll", 2U, 2U, 2U},
      {Str, "ll", 3U, StringRef::npos, 7U},
      {Str, "LL", 2U, 7U, 2U},
      {Str, "LL", 3U, 7U, 7U},
      {Str, "", 0U, 0U, 0U},
      {LongStr, "hello", 0U, 36U, 36U},
      {LongStr, "foo", 0U, 28U, 28U},
      {LongStr, "hell", 2U, 12U, 12U},
      {LongStr, "HELL", 2U, 42U, 12U},
      {LongStr, "", 0U, 0U, 0U}};

  for (auto &E : CharExpectations) {
    EXPECT_EQ(E.Pos, E.Str.find(E.C, E.From));
    EXPECT_EQ(E.LowerPos, E.Str.find_lower(E.C, E.From));
    EXPECT_EQ(E.LowerPos, E.Str.find_lower(toupper(E.C), E.From));
  }

  for (auto &E : StrExpectations) {
    EXPECT_EQ(E.Pos, E.Str.find(E.S, E.From));
    EXPECT_EQ(E.LowerPos, E.Str.find_lower(E.S, E.From));
    EXPECT_EQ(E.LowerPos, E.Str.find_lower(E.S.upper(), E.From));
  }

  EXPECT_EQ(3U, Str.rfind('l'));
  EXPECT_EQ(StringRef::npos, Str.rfind('z'));
  EXPECT_EQ(StringRef::npos, Str.rfind("helloworld"));
  EXPECT_EQ(0U, Str.rfind("hello"));
  EXPECT_EQ(1U, Str.rfind("ello"));
  EXPECT_EQ(StringRef::npos, Str.rfind("zz"));

  EXPECT_EQ(8U, Str.rfind_lower('l'));
  EXPECT_EQ(8U, Str.rfind_lower('L'));
  EXPECT_EQ(StringRef::npos, Str.rfind_lower('z'));
  EXPECT_EQ(StringRef::npos, Str.rfind_lower("HELLOWORLD"));
  EXPECT_EQ(5U, Str.rfind("HELLO"));
  EXPECT_EQ(6U, Str.rfind("ELLO"));
  EXPECT_EQ(StringRef::npos, Str.rfind("ZZ"));

  EXPECT_EQ(2U, Str.find_first_of('l'));
  EXPECT_EQ(1U, Str.find_first_of("el"));
  EXPECT_EQ(StringRef::npos, Str.find_first_of("xyz"));

  Str = "hello";
  EXPECT_EQ(1U, Str.find_first_not_of('h'));
  EXPECT_EQ(4U, Str.find_first_not_of("hel"));
  EXPECT_EQ(StringRef::npos, Str.find_first_not_of("hello"));

  EXPECT_EQ(3U, Str.find_last_not_of('o'));
  EXPECT_EQ(1U, Str.find_last_not_of("lo"));
  EXPECT_EQ(StringRef::npos, Str.find_last_not_of("helo"));
}

TEST(StringRefTest, Count) {
  StringRef Str("hello");
  EXPECT_EQ(2U, Str.count('l'));
  EXPECT_EQ(1U, Str.count('o'));
  EXPECT_EQ(0U, Str.count('z'));
  EXPECT_EQ(0U, Str.count("helloworld"));
  EXPECT_EQ(1U, Str.count("hello"));
  EXPECT_EQ(1U, Str.count("ello"));
  EXPECT_EQ(0U, Str.count("zz"));
}

TEST(StringRefTest, EditDistance) {
  StringRef Hello("hello");
  EXPECT_EQ(2U, Hello.edit_distance("hill"));

  StringRef Industry("industry");
  EXPECT_EQ(6U, Industry.edit_distance("interest"));

  StringRef Soylent("soylent green is people");
  EXPECT_EQ(19U, Soylent.edit_distance("people soiled our green"));
  EXPECT_EQ(26U, Soylent.edit_distance("people soiled our green",
                                      /* allow replacements = */ false));
  EXPECT_EQ(9U, Soylent.edit_distance("people soiled our green",
                                      /* allow replacements = */ true,
                                      /* max edit distance = */ 8));
  EXPECT_EQ(53U, Soylent.edit_distance("people soiled our green "
                                       "people soiled our green "
                                       "people soiled our green "));
}

TEST(StringRefTest, Misc) {
  std::string Storage;
  raw_string_ostream OS(Storage);
  OS << StringRef("hello");
  EXPECT_EQ("hello", OS.str());
}

TEST(StringRefTest, Hashing) {
  EXPECT_EQ(hash_value(std::string()), hash_value(StringRef()));
  EXPECT_EQ(hash_value(std::string()), hash_value(StringRef("")));
  std::string S = "hello world";
  hash_code H = hash_value(S);
  EXPECT_EQ(H, hash_value(StringRef("hello world")));
  EXPECT_EQ(H, hash_value(StringRef(S)));
  EXPECT_NE(H, hash_value(StringRef("hello worl")));
  EXPECT_EQ(hash_value(std::string("hello worl")),
            hash_value(StringRef("hello worl")));
  EXPECT_NE(H, hash_value(StringRef("hello world ")));
  EXPECT_EQ(hash_value(std::string("hello world ")),
            hash_value(StringRef("hello world ")));
  EXPECT_EQ(H, hash_value(StringRef("hello world\0")));
  EXPECT_NE(hash_value(std::string("ello worl")),
            hash_value(StringRef("hello world").slice(1, -1)));
}

struct UnsignedPair {
  const char *Str;
  uint64_t Expected;
} Unsigned[] =
  { {"0", 0}
  , {"255", 255}
  , {"256", 256}
  , {"65535", 65535}
  , {"65536", 65536}
  , {"4294967295", 4294967295ULL}
  , {"4294967296", 4294967296ULL}
  , {"18446744073709551615", 18446744073709551615ULL}
  , {"042", 34}
  , {"0x42", 66}
  , {"0b101010", 42}
  };

struct SignedPair {
  const char *Str;
  int64_t Expected;
} Signed[] =
  { {"0", 0}
  , {"-0", 0}
  , {"127", 127}
  , {"128", 128}
  , {"-128", -128}
  , {"-129", -129}
  , {"32767", 32767}
  , {"32768", 32768}
  , {"-32768", -32768}
  , {"-32769", -32769}
  , {"2147483647", 2147483647LL}
  , {"2147483648", 2147483648LL}
  , {"-2147483648", -2147483648LL}
  , {"-2147483649", -2147483649LL}
  , {"-9223372036854775808", -(9223372036854775807LL) - 1}
  , {"042", 34}
  , {"0x42", 66}
  , {"0b101010", 42}
  , {"-042", -34}
  , {"-0x42", -66}
  , {"-0b101010", -42}
  };

TEST(StringRefTest, getAsInteger) {
  uint8_t U8;
  uint16_t U16;
  uint32_t U32;
  uint64_t U64;

  for (size_t i = 0; i < array_lengthof(Unsigned); ++i) {
    bool U8Success = StringRef(Unsigned[i].Str).getAsInteger(0, U8);
    if (static_cast<uint8_t>(Unsigned[i].Expected) == Unsigned[i].Expected) {
      ASSERT_FALSE(U8Success);
      EXPECT_EQ(U8, Unsigned[i].Expected);
    } else {
      ASSERT_TRUE(U8Success);
    }
    bool U16Success = StringRef(Unsigned[i].Str).getAsInteger(0, U16);
    if (static_cast<uint16_t>(Unsigned[i].Expected) == Unsigned[i].Expected) {
      ASSERT_FALSE(U16Success);
      EXPECT_EQ(U16, Unsigned[i].Expected);
    } else {
      ASSERT_TRUE(U16Success);
    }
    bool U32Success = StringRef(Unsigned[i].Str).getAsInteger(0, U32);
    if (static_cast<uint32_t>(Unsigned[i].Expected) == Unsigned[i].Expected) {
      ASSERT_FALSE(U32Success);
      EXPECT_EQ(U32, Unsigned[i].Expected);
    } else {
      ASSERT_TRUE(U32Success);
    }
    bool U64Success = StringRef(Unsigned[i].Str).getAsInteger(0, U64);
    if (static_cast<uint64_t>(Unsigned[i].Expected) == Unsigned[i].Expected) {
      ASSERT_FALSE(U64Success);
      EXPECT_EQ(U64, Unsigned[i].Expected);
    } else {
      ASSERT_TRUE(U64Success);
    }
  }

  int8_t S8;
  int16_t S16;
  int32_t S32;
  int64_t S64;

  for (size_t i = 0; i < array_lengthof(Signed); ++i) {
    bool S8Success = StringRef(Signed[i].Str).getAsInteger(0, S8);
    if (static_cast<int8_t>(Signed[i].Expected) == Signed[i].Expected) {
      ASSERT_FALSE(S8Success);
      EXPECT_EQ(S8, Signed[i].Expected);
    } else {
      ASSERT_TRUE(S8Success);
    }
    bool S16Success = StringRef(Signed[i].Str).getAsInteger(0, S16);
    if (static_cast<int16_t>(Signed[i].Expected) == Signed[i].Expected) {
      ASSERT_FALSE(S16Success);
      EXPECT_EQ(S16, Signed[i].Expected);
    } else {
      ASSERT_TRUE(S16Success);
    }
    bool S32Success = StringRef(Signed[i].Str).getAsInteger(0, S32);
    if (static_cast<int32_t>(Signed[i].Expected) == Signed[i].Expected) {
      ASSERT_FALSE(S32Success);
      EXPECT_EQ(S32, Signed[i].Expected);
    } else {
      ASSERT_TRUE(S32Success);
    }
    bool S64Success = StringRef(Signed[i].Str).getAsInteger(0, S64);
    if (static_cast<int64_t>(Signed[i].Expected) == Signed[i].Expected) {
      ASSERT_FALSE(S64Success);
      EXPECT_EQ(S64, Signed[i].Expected);
    } else {
      ASSERT_TRUE(S64Success);
    }
  }
}


static const char* BadStrings[] = {
    ""                      // empty string
  , "18446744073709551617"  // value just over max
  , "123456789012345678901" // value way too large
  , "4t23v"                 // illegal decimal characters
  , "0x123W56"              // illegal hex characters
  , "0b2"                   // illegal bin characters
  , "08"                    // illegal oct characters
  , "0o8"                   // illegal oct characters
  , "-123"                  // negative unsigned value
  , "0x"
  , "0b"
};


TEST(StringRefTest, getAsUnsignedIntegerBadStrings) {
  unsigned long long U64;
  for (size_t i = 0; i < array_lengthof(BadStrings); ++i) {
    bool IsBadNumber = StringRef(BadStrings[i]).getAsInteger(0, U64);
    ASSERT_TRUE(IsBadNumber);
  }
}

struct ConsumeUnsignedPair {
  const char *Str;
  uint64_t Expected;
  const char *Leftover;
} ConsumeUnsigned[] = {
    {"0", 0, ""},
    {"255", 255, ""},
    {"256", 256, ""},
    {"65535", 65535, ""},
    {"65536", 65536, ""},
    {"4294967295", 4294967295ULL, ""},
    {"4294967296", 4294967296ULL, ""},
    {"255A376", 255, "A376"},
    {"18446744073709551615", 18446744073709551615ULL, ""},
    {"18446744073709551615ABC", 18446744073709551615ULL, "ABC"},
    {"042", 34, ""},
    {"0x42", 66, ""},
    {"0x42-0x34", 66, "-0x34"},
    {"0b101010", 42, ""},
    {"0429F", 042, "9F"},            // Auto-sensed octal radix, invalid digit
    {"0x42G12", 0x42, "G12"},        // Auto-sensed hex radix, invalid digit
    {"0b10101020101", 42, "20101"}}; // Auto-sensed binary radix, invalid digit.

struct ConsumeSignedPair {
  const char *Str;
  int64_t Expected;
  const char *Leftover;
} ConsumeSigned[] = {
    {"0", 0, ""},
    {"-0", 0, ""},
    {"0-1", 0, "-1"},
    {"-0-1", 0, "-1"},
    {"127", 127, ""},
    {"128", 128, ""},
    {"127-1", 127, "-1"},
    {"128-1", 128, "-1"},
    {"-128", -128, ""},
    {"-129", -129, ""},
    {"-128-1", -128, "-1"},
    {"-129-1", -129, "-1"},
    {"32767", 32767, ""},
    {"32768", 32768, ""},
    {"32767-1", 32767, "-1"},
    {"32768-1", 32768, "-1"},
    {"-32768", -32768, ""},
    {"-32769", -32769, ""},
    {"-32768-1", -32768, "-1"},
    {"-32769-1", -32769, "-1"},
    {"2147483647", 2147483647LL, ""},
    {"2147483648", 2147483648LL, ""},
    {"2147483647-1", 2147483647LL, "-1"},
    {"2147483648-1", 2147483648LL, "-1"},
    {"-2147483648", -2147483648LL, ""},
    {"-2147483649", -2147483649LL, ""},
    {"-2147483648-1", -2147483648LL, "-1"},
    {"-2147483649-1", -2147483649LL, "-1"},
    {"-9223372036854775808", -(9223372036854775807LL) - 1, ""},
    {"-9223372036854775808-1", -(9223372036854775807LL) - 1, "-1"},
    {"042", 34, ""},
    {"042-1", 34, "-1"},
    {"0x42", 66, ""},
    {"0x42-1", 66, "-1"},
    {"0b101010", 42, ""},
    {"0b101010-1", 42, "-1"},
    {"-042", -34, ""},
    {"-042-1", -34, "-1"},
    {"-0x42", -66, ""},
    {"-0x42-1", -66, "-1"},
    {"-0b101010", -42, ""},
    {"-0b101010-1", -42, "-1"}};

TEST(StringRefTest, consumeIntegerUnsigned) {
  uint8_t U8;
  uint16_t U16;
  uint32_t U32;
  uint64_t U64;

  for (size_t i = 0; i < array_lengthof(ConsumeUnsigned); ++i) {
    StringRef Str = ConsumeUnsigned[i].Str;
    bool U8Success = Str.consumeInteger(0, U8);
    if (static_cast<uint8_t>(ConsumeUnsigned[i].Expected) ==
        ConsumeUnsigned[i].Expected) {
      ASSERT_FALSE(U8Success);
      EXPECT_EQ(U8, ConsumeUnsigned[i].Expected);
      EXPECT_EQ(Str, ConsumeUnsigned[i].Leftover);
    } else {
      ASSERT_TRUE(U8Success);
    }

    Str = ConsumeUnsigned[i].Str;
    bool U16Success = Str.consumeInteger(0, U16);
    if (static_cast<uint16_t>(ConsumeUnsigned[i].Expected) ==
        ConsumeUnsigned[i].Expected) {
      ASSERT_FALSE(U16Success);
      EXPECT_EQ(U16, ConsumeUnsigned[i].Expected);
      EXPECT_EQ(Str, ConsumeUnsigned[i].Leftover);
    } else {
      ASSERT_TRUE(U16Success);
    }

    Str = ConsumeUnsigned[i].Str;
    bool U32Success = Str.consumeInteger(0, U32);
    if (static_cast<uint32_t>(ConsumeUnsigned[i].Expected) ==
        ConsumeUnsigned[i].Expected) {
      ASSERT_FALSE(U32Success);
      EXPECT_EQ(U32, ConsumeUnsigned[i].Expected);
      EXPECT_EQ(Str, ConsumeUnsigned[i].Leftover);
    } else {
      ASSERT_TRUE(U32Success);
    }

    Str = ConsumeUnsigned[i].Str;
    bool U64Success = Str.consumeInteger(0, U64);
    if (static_cast<uint64_t>(ConsumeUnsigned[i].Expected) ==
        ConsumeUnsigned[i].Expected) {
      ASSERT_FALSE(U64Success);
      EXPECT_EQ(U64, ConsumeUnsigned[i].Expected);
      EXPECT_EQ(Str, ConsumeUnsigned[i].Leftover);
    } else {
      ASSERT_TRUE(U64Success);
    }
  }
}

TEST(StringRefTest, consumeIntegerSigned) {
  int8_t S8;
  int16_t S16;
  int32_t S32;
  int64_t S64;

  for (size_t i = 0; i < array_lengthof(ConsumeSigned); ++i) {
    StringRef Str = ConsumeSigned[i].Str;
    bool S8Success = Str.consumeInteger(0, S8);
    if (static_cast<int8_t>(ConsumeSigned[i].Expected) ==
        ConsumeSigned[i].Expected) {
      ASSERT_FALSE(S8Success);
      EXPECT_EQ(S8, ConsumeSigned[i].Expected);
      EXPECT_EQ(Str, ConsumeSigned[i].Leftover);
    } else {
      ASSERT_TRUE(S8Success);
    }

    Str = ConsumeSigned[i].Str;
    bool S16Success = Str.consumeInteger(0, S16);
    if (static_cast<int16_t>(ConsumeSigned[i].Expected) ==
        ConsumeSigned[i].Expected) {
      ASSERT_FALSE(S16Success);
      EXPECT_EQ(S16, ConsumeSigned[i].Expected);
      EXPECT_EQ(Str, ConsumeSigned[i].Leftover);
    } else {
      ASSERT_TRUE(S16Success);
    }

    Str = ConsumeSigned[i].Str;
    bool S32Success = Str.consumeInteger(0, S32);
    if (static_cast<int32_t>(ConsumeSigned[i].Expected) ==
        ConsumeSigned[i].Expected) {
      ASSERT_FALSE(S32Success);
      EXPECT_EQ(S32, ConsumeSigned[i].Expected);
      EXPECT_EQ(Str, ConsumeSigned[i].Leftover);
    } else {
      ASSERT_TRUE(S32Success);
    }

    Str = ConsumeSigned[i].Str;
    bool S64Success = Str.consumeInteger(0, S64);
    if (static_cast<int64_t>(ConsumeSigned[i].Expected) ==
        ConsumeSigned[i].Expected) {
      ASSERT_FALSE(S64Success);
      EXPECT_EQ(S64, ConsumeSigned[i].Expected);
      EXPECT_EQ(Str, ConsumeSigned[i].Leftover);
    } else {
      ASSERT_TRUE(S64Success);
    }
  }
}

struct GetDoubleStrings {
  const char *Str;
  bool AllowInexact;
  bool ShouldFail;
  double D;
} DoubleStrings[] = {{"0", false, false, 0.0},
                     {"0.0", false, false, 0.0},
                     {"-0.0", false, false, -0.0},
                     {"123.45", false, true, 123.45},
                     {"123.45", true, false, 123.45},
                     {"1.8e308", true, false, std::numeric_limits<double>::infinity()},
                     {"1.8e308", false, true, std::numeric_limits<double>::infinity()},
                     {"0x0.0000000000001P-1023", false, true, 0.0},
                     {"0x0.0000000000001P-1023", true, false, 0.0},
                    };

TEST(StringRefTest, getAsDouble) {
  for (const auto &Entry : DoubleStrings) {
    double Result;
    StringRef S(Entry.Str);
    EXPECT_EQ(Entry.ShouldFail, S.getAsDouble(Result, Entry.AllowInexact));
    if (!Entry.ShouldFail) {
      EXPECT_EQ(Result, Entry.D);
    }
  }
}

static const char *join_input[] = { "a", "b", "c" };
static const char join_result1[] = "a";
static const char join_result2[] = "a:b:c";
static const char join_result3[] = "a::b::c";

TEST(StringRefTest, joinStrings) {
  std::vector<StringRef> v1;
  std::vector<std::string> v2;
  for (size_t i = 0; i < array_lengthof(join_input); ++i) {
    v1.push_back(join_input[i]);
    v2.push_back(join_input[i]);
  }

  bool v1_join1 = join(v1.begin(), v1.begin() + 1, ":") == join_result1;
  EXPECT_TRUE(v1_join1);
  bool v1_join2 = join(v1.begin(), v1.end(), ":") == join_result2;
  EXPECT_TRUE(v1_join2);
  bool v1_join3 = join(v1.begin(), v1.end(), "::") == join_result3;
  EXPECT_TRUE(v1_join3);

  bool v2_join1 = join(v2.begin(), v2.begin() + 1, ":") == join_result1;
  EXPECT_TRUE(v2_join1);
  bool v2_join2 = join(v2.begin(), v2.end(), ":") == join_result2;
  EXPECT_TRUE(v2_join2);
  bool v2_join3 = join(v2.begin(), v2.end(), "::") == join_result3;
  EXPECT_TRUE(v2_join3);
  v2_join3 = join(v2, "::") == join_result3;
  EXPECT_TRUE(v2_join3);
}


TEST(StringRefTest, AllocatorCopy) {
  BumpPtrAllocator Alloc;
  // First test empty strings.  We don't want these to allocate anything on the
  // allocator.
  StringRef StrEmpty = "";
  StringRef StrEmptyc = StrEmpty.copy(Alloc);
  EXPECT_TRUE(StrEmpty.equals(StrEmptyc));
  EXPECT_EQ(StrEmptyc.data(), nullptr);
  EXPECT_EQ(StrEmptyc.size(), 0u);
  EXPECT_EQ(Alloc.getTotalMemory(), 0u);

  StringRef Str1 = "hello";
  StringRef Str2 = "bye";
  StringRef Str1c = Str1.copy(Alloc);
  StringRef Str2c = Str2.copy(Alloc);
  EXPECT_TRUE(Str1.equals(Str1c));
  EXPECT_NE(Str1.data(), Str1c.data());
  EXPECT_TRUE(Str2.equals(Str2c));
  EXPECT_NE(Str2.data(), Str2c.data());
}

TEST(StringRefTest, Drop) {
  StringRef Test("StringRefTest::Drop");

  StringRef Dropped = Test.drop_front(5);
  EXPECT_EQ(Dropped, "gRefTest::Drop");

  Dropped = Test.drop_back(5);
  EXPECT_EQ(Dropped, "StringRefTest:");

  Dropped = Test.drop_front(0);
  EXPECT_EQ(Dropped, Test);

  Dropped = Test.drop_back(0);
  EXPECT_EQ(Dropped, Test);

  Dropped = Test.drop_front(Test.size());
  EXPECT_TRUE(Dropped.empty());

  Dropped = Test.drop_back(Test.size());
  EXPECT_TRUE(Dropped.empty());
}

TEST(StringRefTest, Take) {
  StringRef Test("StringRefTest::Take");

  StringRef Taken = Test.take_front(5);
  EXPECT_EQ(Taken, "Strin");

  Taken = Test.take_back(5);
  EXPECT_EQ(Taken, ":Take");

  Taken = Test.take_front(Test.size());
  EXPECT_EQ(Taken, Test);

  Taken = Test.take_back(Test.size());
  EXPECT_EQ(Taken, Test);

  Taken = Test.take_front(0);
  EXPECT_TRUE(Taken.empty());

  Taken = Test.take_back(0);
  EXPECT_TRUE(Taken.empty());
}

TEST(StringRefTest, FindIf) {
  StringRef Punct("Test.String");
  StringRef NoPunct("ABCDEFG");
  StringRef Empty;

  auto IsPunct = [](char c) { return ::ispunct(c); };
  auto IsAlpha = [](char c) { return ::isalpha(c); };
  EXPECT_EQ(4U, Punct.find_if(IsPunct));
  EXPECT_EQ(StringRef::npos, NoPunct.find_if(IsPunct));
  EXPECT_EQ(StringRef::npos, Empty.find_if(IsPunct));

  EXPECT_EQ(4U, Punct.find_if_not(IsAlpha));
  EXPECT_EQ(StringRef::npos, NoPunct.find_if_not(IsAlpha));
  EXPECT_EQ(StringRef::npos, Empty.find_if_not(IsAlpha));
}

TEST(StringRefTest, TakeWhileUntil) {
  StringRef Test("String With 1 Number");

  StringRef Taken = Test.take_while([](char c) { return ::isdigit(c); });
  EXPECT_EQ("", Taken);

  Taken = Test.take_until([](char c) { return ::isdigit(c); });
  EXPECT_EQ("String With ", Taken);

  Taken = Test.take_while([](char c) { return true; });
  EXPECT_EQ(Test, Taken);

  Taken = Test.take_until([](char c) { return true; });
  EXPECT_EQ("", Taken);

  Test = "";
  Taken = Test.take_while([](char c) { return true; });
  EXPECT_EQ("", Taken);
}

TEST(StringRefTest, DropWhileUntil) {
  StringRef Test("String With 1 Number");

  StringRef Taken = Test.drop_while([](char c) { return ::isdigit(c); });
  EXPECT_EQ(Test, Taken);

  Taken = Test.drop_until([](char c) { return ::isdigit(c); });
  EXPECT_EQ("1 Number", Taken);

  Taken = Test.drop_while([](char c) { return true; });
  EXPECT_EQ("", Taken);

  Taken = Test.drop_until([](char c) { return true; });
  EXPECT_EQ(Test, Taken);

  StringRef EmptyString = "";
  Taken = EmptyString.drop_while([](char c) { return true; });
  EXPECT_EQ("", Taken);
}

TEST(StringRefTest, StringLiteral) {
  constexpr StringLiteral Strings[] = {"Foo", "Bar"};
  EXPECT_EQ(StringRef("Foo"), Strings[0]);
  EXPECT_EQ(StringRef("Bar"), Strings[1]);
}

static_assert(is_trivially_copyable<StringRef>::value, "trivially copyable");

} // end anonymous namespace