libcxx/test/std/input.output/string.streams/istringstream/istringstream.cons/string_view.alloc.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20, c++23
  10
  11 // <sstream>
  12
  13 // template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT>>
  14 // class basic_istringstream
  15
  16 // template<class T>
  17 //   basic_istringstream(const T& t, const Allocator& a);
  18
  19 #include <cassert>
  20 #include <concepts>
  21 #include <memory>
  22 #include <sstream>
  23 #include <string>
  24 #include <string_view>
  25
  26 #include "constexpr_char_traits.h"
  27 #include "nasty_string.h"
  28 #include "test_allocator.h"
  29 #include "test_convertible.h"
  30 #include "test_macros.h"
  31
  32 #include "../../helper_string_macros.h"
  33 #include "../../helper_types.h"
  34
  35 template <typename AllocT = std::allocator<nasty_char>>
  36 void test_sfinae_with_nasty_char() {
  37   // nasty_char*
  38   using NStrStream = std::basic_istringstream<nasty_char, nasty_char_traits, AllocT>;
  39
  40   static_assert(std::constructible_from<NStrStream, nasty_char*, AllocT>);
  41   static_assert(test_convertible<NStrStream, nasty_char*, const AllocT>());
  42
  43   // const nasty_char*
  44   static_assert(std::constructible_from<NStrStream, const nasty_char*, AllocT>);
  45   static_assert(test_convertible<NStrStream, const nasty_char*, const AllocT>());
  46 }
  47
  48 template <typename CharT, typename TraitsT = std::char_traits<CharT>, typename AllocT = std::allocator<CharT>>
  49 void test_sfinae() {
  50   using StrStream = std::basic_istringstream<CharT, TraitsT, AllocT>;
  51
  52   // `CharT*`
  53   static_assert(std::constructible_from<StrStream, CharT*, const AllocT>);
  54   static_assert(test_convertible<StrStream, CharT*, const AllocT>());
  55
  56   // `const CharT*`
  57   static_assert(std::constructible_from<StrStream, const CharT*, const AllocT>);
  58   static_assert(test_convertible<StrStream, const CharT*, const AllocT>());
  59
  60   // `std::basic_string_view<CharT>`
  61   static_assert(std::constructible_from<StrStream, const std::basic_string_view<CharT, TraitsT>, const AllocT>);
  62   static_assert(test_convertible<StrStream, std::basic_string_view<CharT, TraitsT>, const AllocT>());
  63
  64   // `std::basic_string<CharT>`
  65   static_assert(std::constructible_from<StrStream, const std::basic_string<CharT, TraitsT>, const AllocT>);
  66   static_assert(test_convertible<StrStream, const std::basic_string<CharT, TraitsT>, const AllocT>());
  67
  68   // ConstConvertibleStringView<CharT>
  69   static_assert(std::constructible_from<StrStream, const ConstConvertibleStringView<CharT, TraitsT>, const AllocT>);
  70   static_assert(test_convertible<StrStream, const ConstConvertibleStringView<CharT, TraitsT>, const AllocT>());
  71
  72   // NonConstConvertibleStringView<CharT>
  73   static_assert(!std::constructible_from<StrStream, NonConstConvertibleStringView<CharT, TraitsT>, const AllocT>);
  74   static_assert(!test_convertible<StrStream, NonConstConvertibleStringView<CharT, TraitsT>, const AllocT>());
  75
  76   static_assert(!std::constructible_from<StrStream, const NonConstConvertibleStringView<CharT, TraitsT>, const AllocT>);
  77   static_assert(!test_convertible<StrStream, const NonConstConvertibleStringView<CharT, TraitsT>, const AllocT>());
  78
  79   // Non-`string-view-like`
  80   static_assert(!std::constructible_from<StrStream, const SomeObject, const AllocT>);
  81   static_assert(!test_convertible<StrStream, const SomeObject, const AllocT>());
  82
  83   // Non-allocator
  84   static_assert(!std::constructible_from<StrStream, const std::basic_string_view<CharT, TraitsT>, const NonAllocator>);
  85   static_assert(!test_convertible<StrStream, const std::basic_string_view<CharT, TraitsT>, const NonAllocator>());
  86 }
  87
  88 template <typename CharT, typename TraitsT = std::char_traits<CharT>, typename AllocT = std::allocator<CharT>>
  89 void test() {
  90   using StrStream = std::basic_istringstream<CharT, TraitsT, AllocT>;
  91
  92   const AllocT allocator;
  93
  94   // const CharT*
  95   {
  96     StrStream ss(CS("zmt"), allocator);
  97     assert(ss.str() == CS("zmt"));
  98     assert(ss.rdbuf()->get_allocator() == allocator);
  99   }
 100   // std::basic_string_view<CharT>
 101   {
 102     const std::basic_string_view<CharT, TraitsT> csv = SV("zmt");
 103     StrStream ss(csv, allocator);
 104     assert(ss.str() == CS("zmt"));
 105     assert(ss.rdbuf()->get_allocator() == allocator);
 106   }
 107   // std::basic_string<CharT>
 108   {
 109     const std::basic_string<CharT, TraitsT, AllocT> cs = ST("zmt", allocator);
 110     StrStream ss(cs, allocator);
 111     assert(ss.str() == CS("zmt"));
 112     assert(ss.rdbuf()->get_allocator() == allocator);
 113   }
 114   // ConstConvertibleStringView<CharT>
 115   {
 116     const ConstConvertibleStringView<CharT, TraitsT> sv{CS("zmt")};
 117     StrStream ss(sv, allocator);
 118     assert(ss.str() == CS("zmt"));
 119     assert(ss.rdbuf()->get_allocator() == allocator);
 120   }
 121 }
 122
 123 int main(int, char**) {
 124   test_sfinae_with_nasty_char();
 125   test_sfinae_with_nasty_char<test_allocator<nasty_char>>();
 126   test_sfinae<char>();
 127   test_sfinae<char, constexpr_char_traits<char>, std::allocator<char>>();
 128   test_sfinae<char, std::char_traits<char>, test_allocator<char>>();
 129   test_sfinae<char, constexpr_char_traits<char>, test_allocator<char>>();
 130   test<char>();
 131   test<char, constexpr_char_traits<char>, std::allocator<char>>();
 132   test<char, std::char_traits<char>, test_allocator<char>>();
 133   test<char, constexpr_char_traits<char>, test_allocator<char>>();
 134 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
 135   test_sfinae<wchar_t>();
 136   test_sfinae<wchar_t, constexpr_char_traits<wchar_t>, std::allocator<wchar_t>>();
 137   test_sfinae<wchar_t, std::char_traits<wchar_t>, test_allocator<wchar_t>>();
 138   test_sfinae<wchar_t, constexpr_char_traits<wchar_t>, test_allocator<wchar_t>>();
 139   test<wchar_t>();
 140   test<wchar_t, constexpr_char_traits<wchar_t>, std::allocator<wchar_t>>();
 141   test<wchar_t, std::char_traits<wchar_t>, test_allocator<wchar_t>>();
 142   test<wchar_t, constexpr_char_traits<wchar_t>, test_allocator<wchar_t>>();
 143 #endif
 144   return 0;
 145 }