text: // Copyright (c) 2012 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include <stddef.h>
  
  #include <string>
  
  #include "base/strings/string16.h"
  #include "base/strings/string_piece.h"
  #include "base/strings/utf_string_conversions.h"
  #include "testing/gtest/include/gtest/gtest.h"
  
  namespace base {
  
  template <typename T>
  class CommonStringPieceTest : public ::testing::Test {
   public:
    static const T as_string(const char* input) {
      return T(input);
    }
    static const T& as_string(const T& input) {
      return input;
    }
  };
  
  template <>
  class CommonStringPieceTest<string16> : public ::testing::Test {
   public:
    static const string16 as_string(const char* input) {
      return ASCIIToUTF16(input);
    }
    static const string16 as_string(const std::string& input) {
      return ASCIIToUTF16(input);
    }
  };
  
  typedef ::testing::Types<std::string, string16> SupportedStringTypes;
  
  TYPED_TEST_SUITE(CommonStringPieceTest, SupportedStringTypes);
  
  TYPED_TEST(CommonStringPieceTest, CheckComparisonOperators) {
  #define CMP_Y(op, x, y)                                                   \
    {                                                                       \
      TypeParam lhs(TestFixture::as_string(x));                             \
      TypeParam rhs(TestFixture::as_string(y));                             \
      ASSERT_TRUE((BasicStringPiece<TypeParam>((lhs.c_str()))               \
                       op BasicStringPiece<TypeParam>((rhs.c_str()))));     \
      ASSERT_TRUE(BasicStringPiece<TypeParam>(lhs) op rhs);                 \
      ASSERT_TRUE(lhs op BasicStringPiece<TypeParam>(rhs));                 \
      ASSERT_TRUE((BasicStringPiece<TypeParam>((lhs.c_str()))               \
                       .compare(BasicStringPiece<TypeParam>((rhs.c_str()))) \
                           op 0));                                          \
    }
  
  #define CMP_N(op, x, y)                                                    \
    {                                                                        \
      TypeParam lhs(TestFixture::as_string(x));                              \
      TypeParam rhs(TestFixture::as_string(y));                              \
      ASSERT_FALSE((BasicStringPiece<TypeParam>((lhs.c_str()))               \
                        op BasicStringPiece<TypeParam>((rhs.c_str()))));     \
      ASSERT_FALSE(BasicStringPiece<TypeParam>(lhs) op rhs);                 \
      ASSERT_FALSE(lhs op BasicStringPiece<TypeParam>(rhs));                 \
      ASSERT_FALSE((BasicStringPiece<TypeParam>((lhs.c_str()))               \
                        .compare(BasicStringPiece<TypeParam>((rhs.c_str()))) \
                            op 0));                                          \
    }
  
    CMP_Y(==, "", "")
    CMP_Y(==, "a", "a")
    CMP_Y(==, "aa", "aa")
    CMP_N(==, "a", "")
    CMP_N(==, "", "a")
    CMP_N(==, "a", "b")
    CMP_N(==, "a", "aa")
    CMP_N(==, "aa", "a")
  
    CMP_N(!=, "", "")
    CMP_N(!=, "a", "a")
    CMP_N(!=, "aa", "aa")
    CMP_Y(!=, "a", "")
    CMP_Y(!=, "", "a")
    CMP_Y(!=, "a", "b")
    CMP_Y(!=, "a", "aa")
    CMP_Y(!=, "aa", "a")
  
    CMP_Y(<, "a", "b")
    CMP_Y(<, "a", "aa")
    CMP_Y(<, "aa", "b")
    CMP_Y(<, "aa", "bb")
    CMP_N(<, "a", "a")
    CMP_N(<, "b", "a")
    CMP_N(<, "aa", "a")
    CMP_N(<, "b", "aa")
    CMP_N(<, "bb", "aa")
  
    CMP_Y(<=, "a", "a")
    CMP_Y(<=, "a", "b")
    CMP_Y(<=, "a", "aa")
    CMP_Y(<=, "aa", "b")
    CMP_Y(<=, "aa", "bb")
    CMP_N(<=, "b", "a")
    CMP_N(<=, "aa", "a")
    CMP_N(<=, "b", "aa")
    CMP_N(<=, "bb", "aa")
  
    CMP_N(>=, "a", "b")
    CMP_N(>=, "a", "aa")
    CMP_N(>=, "aa", "b")
    CMP_N(>=, "aa", "bb")
    CMP_Y(>=, "a", "a")
    CMP_Y(>=, "b", "a")
    CMP_Y(>=, "aa", "a")
    CMP_Y(>=, "b", "aa")
    CMP_Y(>=, "bb", "aa")
  
    CMP_N(>, "a", "a")
    CMP_N(>, "a", "b")
    CMP_N(>, "a", "aa")
    CMP_N(>, "aa", "b")
    CMP_N(>, "aa", "bb")
    CMP_Y(>, "b", "a")
    CMP_Y(>, "aa", "a")
    CMP_Y(>, "b", "aa")
    CMP_Y(>, "bb", "aa")
  
    std::string x;
    for (int i = 0; i < 256; i++) {
      x += 'a';
      std::string y = x;
      CMP_Y(==, x, y);
      for (int j = 0; j < i; j++) {
        std::string z = x;
        z[j] = 'b';       // Differs in position 'j'
        CMP_N(==, x, z);
      }
    }
  
  #undef CMP_Y
  #undef CMP_N
  }
  
  TYPED_TEST(CommonStringPieceTest, CheckSTL) {
    TypeParam alphabet(TestFixture::as_string("abcdefghijklmnopqrstuvwxyz"));
    TypeParam abc(TestFixture::as_string("abc"));
    TypeParam xyz(TestFixture::as_string("xyz"));
    TypeParam foobar(TestFixture::as_string("foobar"));
  
    BasicStringPiece<TypeParam> a(alphabet);
    BasicStringPiece<TypeParam> b(abc);
    BasicStringPiece<TypeParam> c(xyz);
    BasicStringPiece<TypeParam> d(foobar);
    BasicStringPiece<TypeParam> e;
    TypeParam temp(TestFixture::as_string("123"));
    temp += static_cast<typename TypeParam::value_type>(0);
    temp += TestFixture::as_string("456");
    BasicStringPiece<TypeParam> f(temp);
  
    ASSERT_EQ(a[6], static_cast<typename TypeParam::value_type>('g'));
    ASSERT_EQ(b[0], static_cast<typename TypeParam::value_type>('a'));
    ASSERT_EQ(c[2], static_cast<typename TypeParam::value_type>('z'));
    ASSERT_EQ(f[3], static_cast<typename TypeParam::value_type>('\0'));
    ASSERT_EQ(f[5], static_cast<typename TypeParam::value_type>('5'));
  
    ASSERT_EQ(*d.data(), static_cast<typename TypeParam::value_type>('f'));
    ASSERT_EQ(d.data()[5], static_cast<typename TypeParam::value_type>('r'));
    ASSERT_EQ(e.data(), nullptr);
  
    ASSERT_EQ(*a.begin(), static_cast<typename TypeParam::value_type>('a'));
    ASSERT_EQ(*(b.begin() + 2), static_cast<typename TypeParam::value_type>('c'));
    ASSERT_EQ(*(c.end() - 1), static_cast<typename TypeParam::value_type>('z'));
  
    ASSERT_EQ(*a.rbegin(), static_cast<typename TypeParam::value_type>('z'));
    ASSERT_EQ(*(b.rbegin() + 2),
              static_cast<typename TypeParam::value_type>('a'));
    ASSERT_EQ(*(c.rend() - 1), static_cast<typename TypeParam::value_type>('x'));
    ASSERT_EQ(a.rbegin() + 26, a.rend());
  
    ASSERT_EQ(a.size(), 26U);
    ASSERT_EQ(b.size(), 3U);
    ASSERT_EQ(c.size(), 3U);
    ASSERT_EQ(d.size(), 6U);
    ASSERT_EQ(e.size(), 0U);
    ASSERT_EQ(f.size(), 7U);
  
    ASSERT_TRUE(!d.empty());
    ASSERT_TRUE(d.begin() != d.end());
    ASSERT_EQ(d.begin() + 6, d.end());
  
    ASSERT_TRUE(e.empty());
    ASSERT_EQ(e.begin(), e.end());
  
    d = BasicStringPiece<TypeParam>();
    ASSERT_EQ(d.size(), 0U);
    ASSERT_TRUE(d.empty());
    ASSERT_EQ(d.data(), nullptr);
    ASSERT_EQ(d.begin(), d.end());
  
    ASSERT_GE(a.max_size(), a.capacity());
    ASSERT_GE(a.capacity(), a.size());
  }
  
  TYPED_TEST(CommonStringPieceTest, CheckFind) {
    typedef BasicStringPiece<TypeParam> Piece;
  
    TypeParam alphabet(TestFixture::as_string("abcdefghijklmnopqrstuvwxyz"));
    TypeParam abc(TestFixture::as_string("abc"));
    TypeParam xyz(TestFixture::as_string("xyz"));
    TypeParam foobar(TestFixture::as_string("foobar"));
  
    BasicStringPiece<TypeParam> a(alphabet);
    BasicStringPiece<TypeParam> b(abc);
    BasicStringPiece<TypeParam> c(xyz);
    BasicStringPiece<TypeParam> d(foobar);
  
    d = Piece();
    Piece e;
    TypeParam temp(TestFixture::as_string("123"));
    temp.push_back('\0');
    temp += TestFixture::as_string("456");
    Piece f(temp);
  
    typename TypeParam::value_type buf[4] = { '%', '%', '%', '%' };
    ASSERT_EQ(a.copy(buf, 4), 4U);
    ASSERT_EQ(buf[0], a[0]);
    ASSERT_EQ(buf[1], a[1]);
    ASSERT_EQ(buf[2], a[2]);
    ASSERT_EQ(buf[3], a[3]);
    ASSERT_EQ(a.copy(buf, 3, 7), 3U);
    ASSERT_EQ(buf[0], a[7]);
    ASSERT_EQ(buf[1], a[8]);
    ASSERT_EQ(buf[2], a[9]);
    ASSERT_EQ(buf[3], a[3]);
    ASSERT_EQ(c.copy(buf, 99), 3U);
    ASSERT_EQ(buf[0], c[0]);
    ASSERT_EQ(buf[1], c[1]);
    ASSERT_EQ(buf[2], c[2]);
    ASSERT_EQ(buf[3], a[3]);
  
    ASSERT_EQ(Piece::npos, TypeParam::npos);
  
    ASSERT_EQ(a.find(b), 0U);
    ASSERT_EQ(a.find(b, 1), Piece::npos);
    ASSERT_EQ(a.find(c), 23U);
    ASSERT_EQ(a.find(c, 9), 23U);
    ASSERT_EQ(a.find(c, Piece::npos), Piece::npos);
    ASSERT_EQ(b.find(c), Piece::npos);
    ASSERT_EQ(b.find(c, Piece::npos), Piece::npos);
    ASSERT_EQ(a.find(d), 0U);
    ASSERT_EQ(a.find(e), 0U);
    ASSERT_EQ(a.find(d, 12), 12U);
    ASSERT_EQ(a.find(e, 17), 17U);
    TypeParam not_found(TestFixture::as_string("xx not found bb"));
    Piece g(not_found);
    ASSERT_EQ(a.find(g), Piece::npos);
    // empty string nonsense
    ASSERT_EQ(d.find(b), Piece::npos);
    ASSERT_EQ(e.find(b), Piece::npos);
    ASSERT_EQ(d.find(b, 4), Piece::npos);
    ASSERT_EQ(e.find(b, 7), Piece::npos);
  
    size_t empty_search_pos = TypeParam().find(TypeParam());
    ASSERT_EQ(d.find(d), empty_search_pos);
    ASSERT_EQ(d.find(e), empty_search_pos);
    ASSERT_EQ(e.find(d), empty_search_pos);
    ASSERT_EQ(e.find(e), empty_search_pos);
    ASSERT_EQ(d.find(d, 4), std::string().find(std::string(), 4));
    ASSERT_EQ(d.find(e, 4), std::string().find(std::string(), 4));
    ASSERT_EQ(e.find(d, 4), std::string().find(std::string(), 4));
    ASSERT_EQ(e.find(e, 4), std::string().find(std::string(), 4));
  
    constexpr typename TypeParam::value_type kNul = '\0';
    ASSERT_EQ(a.find('a'), 0U);
    ASSERT_EQ(a.find('c'), 2U);
    ASSERT_EQ(a.find('z'), 25U);
    ASSERT_EQ(a.find('$'), Piece::npos);
    ASSERT_EQ(a.find(kNul), Piece::npos);
    ASSERT_EQ(f.find(kNul), 3U);
    ASSERT_EQ(f.find('3'), 2U);
    ASSERT_EQ(f.find('5'), 5U);
    ASSERT_EQ(g.find('o'), 4U);
    ASSERT_EQ(g.find('o', 4), 4U);
    ASSERT_EQ(g.find('o', 5), 8U);
    ASSERT_EQ(a.find('b', 5), Piece::npos);
    // empty string nonsense
    ASSERT_EQ(d.find(kNul), Piece::npos);
    ASSERT_EQ(e.find(kNul), Piece::npos);
    ASSERT_EQ(d.find(kNul, 4), Piece::npos);
    ASSERT_EQ(e.find(kNul, 7), Piece::npos);
    ASSERT_EQ(d.find('x'), Piece::npos);
    ASSERT_EQ(e.find('x'), Piece::npos);
    ASSERT_EQ(d.find('x', 4), Piece::npos);
    ASSERT_EQ(e.find('x', 7), Piece::npos);
  
    ASSERT_EQ(a.find(b.data(), 1, 0), 1U);
    ASSERT_EQ(a.find(c.data(), 9, 0), 9U);
    ASSERT_EQ(a.find(c.data(), Piece::npos, 0), Piece::npos);
    ASSERT_EQ(b.find(c.data(), Piece::npos, 0), Piece::npos);
    ASSERT_EQ(a.find(d.data(), 12, 0), 12U);
    ASSERT_EQ(a.find(e.data(), 17, 0), 17U);
    // empty string nonsense
    ASSERT_EQ(d.find(b.data(), 4, 0), Piece::npos);
    ASSERT_EQ(e.find(b.data(), 7, 0), Piece::npos);
  
    ASSERT_EQ(a.find(b.data(), 1), Piece::npos);
    ASSERT_EQ(a.find(c.data(), 9), 23U);
    ASSERT_EQ(a.find(c.data(), Piece::npos), Piece::npos);
    ASSERT_EQ(b.find(c.data(), Piece::npos), Piece::npos);
    ASSERT_EQ(a.find(d.data(), 12), 12U);
    ASSERT_EQ(a.find(e.data(), 17), 17U);
    // empty string nonsense
    ASSERT_EQ(d.find(b.data(), 4), Piece::npos);
    ASSERT_EQ(e.find(b.data(), 7), Piece::npos);
  
    ASSERT_EQ(d.find(d.data(), 4, 0),
              std::string().find(std::string().data(), 4, 0));
    ASSERT_EQ(d.find(e.data(), 4, 1),
              std::string().find(std::string().data(), 4, 1));
    ASSERT_EQ(e.find(d.data(), 4, 2),
              std::string().find(std::string().data(), 4, 2));
    ASSERT_EQ(e.find(e.data(), 4, 3),
              std::string().find(std::string().data(), 4, 3));
  
    ASSERT_EQ(a.rfind(b), 0U);
    ASSERT_EQ(a.rfind(b, 1), 0U);
    ASSERT_EQ(a.rfind(c), 23U);
    ASSERT_EQ(a.rfind(c, 22U), Piece::npos);
    ASSERT_EQ(a.rfind(c, 1U), Piece::npos);
    ASSERT_EQ(a.rfind(c, 0U), Piece::npos);
    ASSERT_EQ(b.rfind(c), Piece::npos);
    ASSERT_EQ(b.rfind(c, 0U), Piece::npos);
    ASSERT_EQ(a.rfind(d), static_cast<size_t>(a.rfind(TypeParam())));
    ASSERT_EQ(a.rfind(e), a.rfind(TypeParam()));
    ASSERT_EQ(a.rfind(d), static_cast<size_t>(TypeParam(a).rfind(TypeParam())));
    ASSERT_EQ(a.rfind(e), TypeParam(a).rfind(TypeParam()));
    ASSERT_EQ(a.rfind(d, 12), 12U);
    ASSERT_EQ(a.rfind(e, 17), 17U);
    ASSERT_EQ(a.rfind(g), Piece::npos);
    ASSERT_EQ(d.rfind(b), Piece::npos);
    ASSERT_EQ(e.rfind(b), Piece::npos);
    ASSERT_EQ(d.rfind(b, 4), Piece::npos);
    ASSERT_EQ(e.rfind(b, 7), Piece::npos);
    // empty string nonsense
    ASSERT_EQ(d.rfind(d, 4), std::string().rfind(std::string()));
    ASSERT_EQ(e.rfind(d, 7), std::string().rfind(std::string()));
    ASSERT_EQ(d.rfind(e, 4), std::string().rfind(std::string()));
    ASSERT_EQ(e.rfind(e, 7), std::string().rfind(std::string()));
    ASSERT_EQ(d.rfind(d), std::string().rfind(std::string()));
    ASSERT_EQ(e.rfind(d), std::string().rfind(std::string()));
    ASSERT_EQ(d.rfind(e), std::string().rfind(std::string()));
    ASSERT_EQ(e.rfind(e), std::string().rfind(std::string()));
  
    ASSERT_EQ(g.rfind('o'), 8U);
    ASSERT_EQ(g.rfind('q'), Piece::npos);
    ASSERT_EQ(g.rfind('o', 8), 8U);
    ASSERT_EQ(g.rfind('o', 7), 4U);
    ASSERT_EQ(g.rfind('o', 3), Piece::npos);
    ASSERT_EQ(f.rfind(kNul), 3U);
    ASSERT_EQ(f.rfind(kNul, 12), 3U);
    ASSERT_EQ(f.rfind('3'), 2U);
    ASSERT_EQ(f.rfind('5'), 5U);
    // empty string nonsense
    ASSERT_EQ(d.rfind('o'), Piece::npos);
    ASSERT_EQ(e.rfind('o'), Piece::npos);
    ASSERT_EQ(d.rfind('o', 4), Piece::npos);
    ASSERT_EQ(e.rfind('o', 7), Piece::npos);
  
    ASSERT_EQ(a.rfind(b.data(), 1, 0), 1U);
    ASSERT_EQ(a.rfind(c.data(), 22U, 0), 22U);
    ASSERT_EQ(a.rfind(c.data(), 1U, 0), 1U);
    ASSERT_EQ(a.rfind(c.data(), 0U, 0), 0U);
    ASSERT_EQ(b.rfind(c.data(), 0U, 0), 0U);
    ASSERT_EQ(a.rfind(d.data(), 12, 0), 12U);
    ASSERT_EQ(a.rfind(e.data(), 17, 0), 17U);
    ASSERT_EQ(d.rfind(b.data(), 4, 0), 0U);
    ASSERT_EQ(e.rfind(b.data(), 7, 0), 0U);
  
    // empty string nonsense
    ASSERT_EQ(d.rfind(d.data(), 4), std::string().rfind(std::string()));
    ASSERT_EQ(e.rfind(d.data(), 7), std::string().rfind(std::string()));
    ASSERT_EQ(d.rfind(e.data(), 4), std::string().rfind(std::string()));
    ASSERT_EQ(e.rfind(e.data(), 7), std::string().rfind(std::string()));
  
    TypeParam one_two_three_four(TestFixture::as_string("one,two:three;four"));
    TypeParam comma_colon(TestFixture::as_string(",:"));
    ASSERT_EQ(3U, Piece(one_two_three_four).find_first_of(comma_colon));
    ASSERT_EQ(a.find_first_of(b), 0U);
    ASSERT_EQ(a.find_first_of(b, 0), 0U);
    ASSERT_EQ(a.find_first_of(b, 1), 1U);
    ASSERT_EQ(a.find_first_of(b, 2), 2U);
    ASSERT_EQ(a.find_first_of(b, 3), Piece::npos);
    ASSERT_EQ(a.find_first_of(c), 23U);
    ASSERT_EQ(a.find_first_of(c, 23), 23U);
    ASSERT_EQ(a.find_first_of(c, 24), 24U);
    ASSERT_EQ(a.find_first_of(c, 25), 25U);
    ASSERT_EQ(a.find_first_of(c, 26), Piece::npos);
    ASSERT_EQ(g.find_first_of(b), 13U);
    ASSERT_EQ(g.find_first_of(c), 0U);
    ASSERT_EQ(a.find_first_of(f), Piece::npos);
    ASSERT_EQ(f.find_first_of(a), Piece::npos);
    // empty string nonsense
    ASSERT_EQ(a.find_first_of(d), Piece::npos);
    ASSERT_EQ(a.find_first_of(e), Piece::npos);
    ASSERT_EQ(d.find_first_of(b), Piece::npos);
    ASSERT_EQ(e.find_first_of(b), Piece::npos);
    ASSERT_EQ(d.find_first_of(d), Piece::npos);
    ASSERT_EQ(e.find_first_of(d), Piece::npos);
    ASSERT_EQ(d.find_first_of(e), Piece::npos);
    ASSERT_EQ(e.find_first_of(e), Piece::npos);
  
    ASSERT_EQ(a.find_first_not_of(b), 3U);
    ASSERT_EQ(a.find_first_not_of(c), 0U);
    ASSERT_EQ(b.find_first_not_of(a), Piece::npos);
    ASSERT_EQ(c.find_first_not_of(a), Piece::npos);
    ASSERT_EQ(f.find_first_not_of(a), 0U);
    ASSERT_EQ(a.find_first_not_of(f), 0U);
    ASSERT_EQ(a.find_first_not_of(d), 0U);
    ASSERT_EQ(a.find_first_not_of(e), 0U);
    // empty string nonsense
    ASSERT_EQ(d.find_first_not_of(a), Piece::npos);
    ASSERT_EQ(e.find_first_not_of(a), Piece::npos);
    ASSERT_EQ(d.find_first_not_of(d), Piece::npos);
    ASSERT_EQ(e.find_first_not_of(d), Piece::npos);
    ASSERT_EQ(d.find_first_not_of(e), Piece::npos);
    ASSERT_EQ(e.find_first_not_of(e), Piece::npos);
  
    TypeParam equals(TestFixture::as_string("===="));
    Piece h(equals);
    ASSERT_EQ(h.find_first_not_of('='), Piece::npos);
    ASSERT_EQ(h.find_first_not_of('=', 3), Piece::npos);
    ASSERT_EQ(h.find_first_not_of(kNul), 0U);
    ASSERT_EQ(g.find_first_not_of('x'), 2U);
    ASSERT_EQ(f.find_first_not_of(kNul), 0U);
    ASSERT_EQ(f.find_first_not_of(kNul, 3), 4U);
    ASSERT_EQ(f.find_first_not_of(kNul, 2), 2U);
    // empty string nonsense
    ASSERT_EQ(d.find_first_not_of('x'), Piece::npos);
    ASSERT_EQ(e.find_first_not_of('x'), Piece::npos);
    ASSERT_EQ(d.find_first_not_of(kNul), Piece::npos);
    ASSERT_EQ(e.find_first_not_of(kNul), Piece::npos);
  
    //  Piece g("xx not found bb");
    TypeParam fifty_six(TestFixture::as_string("56"));
    Piece i(fifty_six);
    ASSERT_EQ(h.find_last_of(a), Piece::npos);
    ASSERT_EQ(g.find_last_of(a), g.size()-1);
    ASSERT_EQ(a.find_last_of(b), 2U);
    ASSERT_EQ(a.find_last_of(c), a.size()-1);
    ASSERT_EQ(f.find_last_of(i), 6U);
    ASSERT_EQ(a.find_last_of('a'), 0U);
    ASSERT_EQ(a.find_last_of('b'), 1U);
    ASSERT_EQ(a.find_last_of('z'), 25U);
    ASSERT_EQ(a.find_last_of('a', 5), 0U);
    ASSERT_EQ(a.find_last_of('b', 5), 1U);
    ASSERT_EQ(a.find_last_of('b', 0), Piece::npos);
    ASSERT_EQ(a.find_last_of('z', 25), 25U);
    ASSERT_EQ(a.find_last_of('z', 24), Piece::npos);
    ASSERT_EQ(f.find_last_of(i, 5), 5U);
    ASSERT_EQ(f.find_last_of(i, 6), 6U);
    ASSERT_EQ(f.find_last_of(a, 4), Piece::npos);
    // empty string nonsense
    ASSERT_EQ(f.find_last_of(d), Piece::npos);
    ASSERT_EQ(f.find_last_of(e), Piece::npos);
    ASSERT_EQ(f.find_last_of(d, 4), Piece::npos);
    ASSERT_EQ(f.find_last_of(e, 4), Piece::npos);
    ASSERT_EQ(d.find_last_of(d), Piece::npos);
    ASSERT_EQ(d.find_last_of(e), Piece::npos);
    ASSERT_EQ(e.find_last_of(d), Piece::npos);
    ASSERT_EQ(e.find_last_of(e), Piece::npos);
    ASSERT_EQ(d.find_last_of(f), Piece::npos);
    ASSERT_EQ(e.find_last_of(f), Piece::npos);
    ASSERT_EQ(d.find_last_of(d, 4), Piece::npos);
    ASSERT_EQ(d.find_last_of(e, 4), Piece::npos);
    ASSERT_EQ(e.find_last_of(d, 4), Piece::npos);
    ASSERT_EQ(e.find_last_of(e, 4), Piece::npos);
    ASSERT_EQ(d.find_last_of(f, 4), Piece::npos);
    ASSERT_EQ(e.find_last_of(f, 4), Piece::npos);
  
    ASSERT_EQ(a.find_last_not_of(b), a.size()-1);
    ASSERT_EQ(a.find_last_not_of(c), 22U);
    ASSERT_EQ(b.find_last_not_of(a), Piece::npos);
    ASSERT_EQ(b.find_last_not_of(b), Piece::npos);
    ASSERT_EQ(f.find_last_not_of(i), 4U);
    ASSERT_EQ(a.find_last_not_of(c, 24), 22U);
    ASSERT_EQ(a.find_last_not_of(b, 3), 3U);
    ASSERT_EQ(a.find_last_not_of(b, 2), Piece::npos);
    // empty string nonsense
    ASSERT_EQ(f.find_last_not_of(d), f.size()-1);
    ASSERT_EQ(f.find_last_not_of(e), f.size()-1);
    ASSERT_EQ(f.find_last_not_of(d, 4), 4U);
    ASSERT_EQ(f.find_last_not_of(e, 4), 4U);
    ASSERT_EQ(d.find_last_not_of(d), Piece::npos);
    ASSERT_EQ(d.find_last_not_of(e), Piece::npos);
    ASSERT_EQ(e.find_last_not_of(d), Piece::npos);
    ASSERT_EQ(e.find_last_not_of(e), Piece::npos);
    ASSERT_EQ(d.find_last_not_of(f), Piece::npos);
    ASSERT_EQ(e.find_last_not_of(f), Piece::npos);
    ASSERT_EQ(d.find_last_not_of(d, 4), Piece::npos);
    ASSERT_EQ(d.find_last_not_of(e, 4), Piece::npos);
    ASSERT_EQ(e.find_last_not_of(d, 4), Piece::npos);
    ASSERT_EQ(e.find_last_not_of(e, 4), Piece::npos);
    ASSERT_EQ(d.find_last_not_of(f, 4), Piece::npos);
    ASSERT_EQ(e.find_last_not_of(f, 4), Piece::npos);
  
    ASSERT_EQ(h.find_last_not_of('x'), h.size() - 1);
    ASSERT_EQ(h.find_last_not_of('='), Piece::npos);
    ASSERT_EQ(b.find_last_not_of('c'), 1U);
    ASSERT_EQ(h.find_last_not_of('x', 2), 2U);
    ASSERT_EQ(h.find_last_not_of('=', 2), Piece::npos);
    ASSERT_EQ(b.find_last_not_of('b', 1), 0U);
    // empty string nonsense
    ASSERT_EQ(d.find_last_not_of('x'), Piece::npos);
    ASSERT_EQ(e.find_last_not_of('x'), Piece::npos);
    ASSERT_EQ(d.find_last_not_of(kNul), Piece::npos);
    ASSERT_EQ(e.find_last_not_of(kNul), Piece::npos);
  
    ASSERT_EQ(a.substr(0, 3), b);
    ASSERT_EQ(a.substr(23), c);
    ASSERT_EQ(a.substr(23, 3), c);
    ASSERT_EQ(a.substr(23, 99), c);
    ASSERT_EQ(a.substr(), a);
    ASSERT_EQ(a.substr(0), a);
    ASSERT_EQ(a.substr(3, 2), TestFixture::as_string("de"));
    ASSERT_EQ(d.substr(0, 99), e);
  }
  
  TYPED_TEST(CommonStringPieceTest, CheckCustom) {
    TypeParam foobar(TestFixture::as_string("foobar"));
    BasicStringPiece<TypeParam> a(foobar);
    TypeParam s1(TestFixture::as_string("123"));
    s1 += static_cast<typename TypeParam::value_type>('\0');
    s1 += TestFixture::as_string("456");
    BasicStringPiece<TypeParam> b(s1);
    BasicStringPiece<TypeParam> e;
    TypeParam s2;
  
    // remove_prefix
    BasicStringPiece<TypeParam> c(a);
    c.remove_prefix(3);
    ASSERT_EQ(c, TestFixture::as_string("bar"));
    c = a;
    c.remove_prefix(0);
    ASSERT_EQ(c, a);
    c.remove_prefix(c.size());
    ASSERT_EQ(c, e);
  
    // remove_suffix
    c = a;
    c.remove_suffix(3);
    ASSERT_EQ(c, TestFixture::as_string("foo"));
    c = a;
    c.remove_suffix(0);
    ASSERT_EQ(c, a);
    c.remove_suffix(c.size());
    ASSERT_EQ(c, e);
  
    // assignment
    c = foobar.c_str();
    ASSERT_EQ(c, a);
    c = {foobar.c_str(), 6};
    ASSERT_EQ(c, a);
    c = {foobar.c_str(), 0};
    ASSERT_EQ(c, e);
    c = {foobar.c_str(), 7};  // Note, has an embedded NULL
    ASSERT_NE(c, a);
  
    // operator STRING_TYPE()
    TypeParam s5(TypeParam(a).c_str(), 7);  // Note, has an embedded NULL
    ASSERT_EQ(c, s5);
    TypeParam s6(e);
    ASSERT_TRUE(s6.empty());
  }
  
  TEST(StringPieceTest, CheckCustom) {
    StringPiece a("foobar");
    std::string s1("123");
    s1 += '\0';
    s1 += "456";
    StringPiece b(s1);
    StringPiece e;
    std::string s2;
  
    StringPiece c;
    c = {"foobar", 6};
    ASSERT_EQ(c, a);
    c = {"foobar", 0};
    ASSERT_EQ(c, e);
    c = {"foobar", 7};
    ASSERT_NE(c, a);
  }
  
  TYPED_TEST(CommonStringPieceTest, CheckNULL) {
    BasicStringPiece<TypeParam> s;
    ASSERT_EQ(s.data(), nullptr);
    ASSERT_EQ(s.size(), 0U);
  
    TypeParam str(s);
    ASSERT_EQ(str.length(), 0U);
    ASSERT_EQ(str, TypeParam());
  }
  
  TYPED_TEST(CommonStringPieceTest, CheckComparisons2) {
    TypeParam alphabet(TestFixture::as_string("abcdefghijklmnopqrstuvwxyz"));
    TypeParam alphabet_z(TestFixture::as_string("abcdefghijklmnopqrstuvwxyzz"));
    TypeParam alphabet_y(TestFixture::as_string("abcdefghijklmnopqrstuvwxyy"));
    BasicStringPiece<TypeParam> abc(alphabet);
  
    // check comparison operations on strings longer than 4 bytes.
    ASSERT_EQ(abc, BasicStringPiece<TypeParam>(alphabet));
    ASSERT_EQ(abc.compare(BasicStringPiece<TypeParam>(alphabet)), 0);
  
    ASSERT_TRUE(abc < BasicStringPiece<TypeParam>(alphabet_z));
    ASSERT_LT(abc.compare(BasicStringPiece<TypeParam>(alphabet_z)), 0);
  
    ASSERT_TRUE(abc > BasicStringPiece<TypeParam>(alphabet_y));
    ASSERT_GT(abc.compare(BasicStringPiece<TypeParam>(alphabet_y)), 0);
  }
  
  TYPED_TEST(CommonStringPieceTest, StringCompareNotAmbiguous) {
    ASSERT_TRUE(TestFixture::as_string("hello").c_str() ==
                TestFixture::as_string("hello"));
    ASSERT_TRUE(TestFixture::as_string("hello").c_str() <
                TestFixture::as_string("world"));
  }
  
  TYPED_TEST(CommonStringPieceTest, HeterogenousStringPieceEquals) {
    TypeParam hello(TestFixture::as_string("hello"));
  
    ASSERT_EQ(BasicStringPiece<TypeParam>(hello), hello);
    ASSERT_EQ(hello.c_str(), BasicStringPiece<TypeParam>(hello));
  }
  
  // string16-specific stuff
  TEST(StringPiece16Test, CheckSTL) {
    // Check some non-ascii characters.
    string16 fifth(ASCIIToUTF16("123"));
    fifth.push_back(0x0000);
    fifth.push_back(0xd8c5);
    fifth.push_back(0xdffe);
    StringPiece16 f(fifth);
  
    ASSERT_EQ(f[3], '\0');
    ASSERT_EQ(f[5], static_cast<char16>(0xdffe));
  
    ASSERT_EQ(f.size(), 6U);
  }
  
  
  
  TEST(StringPiece16Test, CheckConversion) {
    // Make sure that we can convert from UTF8 to UTF16 and back. We use a two
    // byte character (G clef) to test this.
    ASSERT_EQ(UTF16ToUTF8(UTF8ToUTF16("\xf0\x9d\x84\x9e")), "\xf0\x9d\x84\x9e");
  }
  
  TYPED_TEST(CommonStringPieceTest, CheckConstructors) {
    TypeParam str(TestFixture::as_string("hello world"));
    TypeParam empty;
  
    ASSERT_EQ(str, BasicStringPiece<TypeParam>(str));
    ASSERT_EQ(str, BasicStringPiece<TypeParam>(str.c_str()));
    ASSERT_TRUE(TestFixture::as_string("hello") ==
                BasicStringPiece<TypeParam>(str.c_str(), 5));
    ASSERT_EQ(
        empty,
        BasicStringPiece<TypeParam>(
            str.c_str(),
            static_cast<typename BasicStringPiece<TypeParam>::size_type>(0)));
    ASSERT_EQ(empty, BasicStringPiece<TypeParam>());
    ASSERT_TRUE(
        empty ==
        BasicStringPiece<TypeParam>(
            nullptr,
            static_cast<typename BasicStringPiece<TypeParam>::size_type>(0)));
    ASSERT_EQ(empty, BasicStringPiece<TypeParam>());
    ASSERT_EQ(empty, BasicStringPiece<TypeParam>(empty));
  }
  
  TEST(StringPieceTest, ConstexprCtor) {
    {
      constexpr StringPiece piece;
      std::ignore = piece;
    }
  
    {
      constexpr StringPiece piece("abc");
      std::ignore = piece;
    }
  
    {
      constexpr StringPiece piece("abc", 2);
      std::ignore = piece;
    }
  }
  
  TEST(StringPieceTest, OutOfBoundsDeath) {
    {
      constexpr StringPiece piece;
      ASSERT_DEATH_IF_SUPPORTED(piece[0], "");
    }
  
    {
      constexpr StringPiece piece;
      ASSERT_DEATH_IF_SUPPORTED(piece.front(), "");
    }
  
    {
      constexpr StringPiece piece;
      ASSERT_DEATH_IF_SUPPORTED(piece.back(), "");
    }
  
    {
      StringPiece piece;
      ASSERT_DEATH_IF_SUPPORTED(piece.remove_suffix(1), "");
    }
  
    {
      StringPiece piece;
      ASSERT_DEATH_IF_SUPPORTED(piece.remove_prefix(1), "");
    }
  
    {
      StringPiece piece;
      ASSERT_DEATH_IF_SUPPORTED(piece.copy(nullptr, 0, 1), "");
    }
  
    {
      StringPiece piece;
      ASSERT_DEATH_IF_SUPPORTED(piece.substr(1), "");
    }
  }
  
  TEST(StringPieceTest, ConstexprData) {
    {
      constexpr StringPiece piece;
      static_assert(piece.data() == nullptr, "");
    }
  
    {
      constexpr StringPiece piece("abc");
      static_assert(piece.data()[0] == 'a', "");
      static_assert(piece.data()[1] == 'b', "");
      static_assert(piece.data()[2] == 'c', "");
    }
  
    {
      constexpr StringPiece piece("def", 2);
      static_assert(piece.data()[0] == 'd', "");
      static_assert(piece.data()[1] == 'e', "");
    }
  }
  
  TEST(StringPieceTest, ConstexprSize) {
    {
      constexpr StringPiece piece;
      static_assert(piece.size() == 0, "");
    }
  
    {
      constexpr StringPiece piece("abc");
      static_assert(piece.size() == 3, "");
    }
  
    {
      constexpr StringPiece piece("def", 2);
      static_assert(piece.size() == 2, "");
    }
  }
  
  TEST(StringPieceTest, ConstexprFront) {
    static_assert(StringPiece("abc").front() == 'a', "");
  }
  
  TEST(StringPieceTest, ConstexprBack) {
    static_assert(StringPiece("abc").back() == 'c', "");
  }
  
  TEST(StringPieceTest, Compare) {
    constexpr StringPiece piece = "def";
  
    static_assert(piece.compare("ab") == 1, "");
    static_assert(piece.compare("abc") == 1, "");
    static_assert(piece.compare("abcd") == 1, "");
    static_assert(piece.compare("de") == 1, "");
    static_assert(piece.compare("def") == 0, "");
    static_assert(piece.compare("defg") == -1, "");
    static_assert(piece.compare("gh") == -1, "");
    static_assert(piece.compare("ghi") == -1, "");
    static_assert(piece.compare("ghij") == -1, "");
  
    static_assert(piece.compare(0, 0, "") == 0, "");
    static_assert(piece.compare(0, 1, "d") == 0, "");
    static_assert(piece.compare(0, 2, "de") == 0, "");
    static_assert(piece.compare(0, 3, "def") == 0, "");
    static_assert(piece.compare(1, 0, "") == 0, "");
    static_assert(piece.compare(1, 1, "e") == 0, "");
    static_assert(piece.compare(1, 2, "ef") == 0, "");
    static_assert(piece.compare(1, 3, "ef") == 0, "");
    static_assert(piece.compare(2, 0, "") == 0, "");
    static_assert(piece.compare(2, 1, "f") == 0, "");
    static_assert(piece.compare(2, 2, "f") == 0, "");
    static_assert(piece.compare(2, 3, "f") == 0, "");
    static_assert(piece.compare(3, 0, "") == 0, "");
    static_assert(piece.compare(3, 1, "") == 0, "");
    static_assert(piece.compare(3, 2, "") == 0, "");
    static_assert(piece.compare(3, 3, "") == 0, "");
  
    static_assert(piece.compare(0, 0, "def", 0) == 0, "");
    static_assert(piece.compare(0, 1, "def", 1) == 0, "");
    static_assert(piece.compare(0, 2, "def", 2) == 0, "");
    static_assert(piece.compare(0, 3, "def", 3) == 0, "");
    static_assert(piece.compare(1, 0, "ef", 0) == 0, "");
    static_assert(piece.compare(1, 1, "ef", 1) == 0, "");
    static_assert(piece.compare(1, 2, "ef", 2) == 0, "");
    static_assert(piece.compare(1, 3, "ef", 2) == 0, "");
    static_assert(piece.compare(2, 0, "f", 0) == 0, "");
    static_assert(piece.compare(2, 1, "f", 1) == 0, "");
    static_assert(piece.compare(2, 2, "f", 1) == 0, "");
    static_assert(piece.compare(2, 3, "f", 1) == 0, "");
    static_assert(piece.compare(3, 0, "", 0) == 0, "");
    static_assert(piece.compare(3, 1, "", 0) == 0, "");
    static_assert(piece.compare(3, 2, "", 0) == 0, "");
    static_assert(piece.compare(3, 3, "", 0) == 0, "");
  
    static_assert(piece.compare(0, 0, "def", 0, 0) == 0, "");
    static_assert(piece.compare(0, 1, "def", 0, 1) == 0, "");
    static_assert(piece.compare(0, 2, "def", 0, 2) == 0, "");
    static_assert(piece.compare(0, 3, "def", 0, 3) == 0, "");
    static_assert(piece.compare(1, 0, "def", 1, 0) == 0, "");
    static_assert(piece.compare(1, 1, "def", 1, 1) == 0, "");
    static_assert(piece.compare(1, 2, "def", 1, 2) == 0, "");
    static_assert(piece.compare(1, 3, "def", 1, 3) == 0, "");
    static_assert(piece.compare(2, 0, "def", 2, 0) == 0, "");
    static_assert(piece.compare(2, 1, "def", 2, 1) == 0, "");
    static_assert(piece.compare(2, 2, "def", 2, 2) == 0, "");
    static_assert(piece.compare(2, 3, "def", 2, 3) == 0, "");
    static_assert(piece.compare(3, 0, "def", 3, 0) == 0, "");
    static_assert(piece.compare(3, 1, "def", 3, 1) == 0, "");
    static_assert(piece.compare(3, 2, "def", 3, 2) == 0, "");
    static_assert(piece.compare(3, 3, "def", 3, 3) == 0, "");
  }
  
  TEST(StringPieceTest, Substr) {
    constexpr StringPiece piece = "abcdefghijklmnopqrstuvwxyz";
  
    static_assert(piece.substr(0, 2) == "ab", "");
    static_assert(piece.substr(0, 3) == "abc", "");
    static_assert(piece.substr(0, 4) == "abcd", "");
    static_assert(piece.substr(3, 2) == "de", "");
    static_assert(piece.substr(3, 3) == "def", "");
    static_assert(piece.substr(23) == "xyz", "");
    static_assert(piece.substr(23, 3) == "xyz", "");
    static_assert(piece.substr(23, 99) == "xyz", "");
    static_assert(piece.substr() == piece, "");
    static_assert(piece.substr(0) == piece, "");
    static_assert(piece.substr(0, 99) == piece, "");
  }
  
  }  // namespace base
  