libcxx/test/std/strings/basic.string/string.cons/string_view.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 // <string>
  10
  11 // explicit basic_string(basic_string_view<CharT, traits> sv, const Allocator& a = Allocator()); // constexpr since C++20
  12
  13 #include <algorithm>
  14 #include <cassert>
  15 #include <stdexcept>
  16 #include <string_view>
  17 #include <string>
  18 #include <type_traits>
  19
  20 #include "min_allocator.h"
  21 #include "test_allocator.h"
  22 #include "test_macros.h"
  23
  24 static_assert(!std::is_convertible<std::string_view, std::string const&>::value, "");
  25 static_assert(!std::is_convertible<std::string_view, std::string>::value, "");
  26
  27 template <class Alloc, class CharT>
  28 TEST_CONSTEXPR_CXX20 void test(std::basic_string_view<CharT> sv) {
  29   typedef std::basic_string<CharT, std::char_traits<CharT>, Alloc> S;
  30   typedef typename S::traits_type T;
  31   {
  32     S s2(sv);
  33     LIBCPP_ASSERT(s2.__invariants());
  34     assert(s2.size() == sv.size());
  35     assert(T::compare(s2.data(), sv.data(), sv.size()) == 0);
  36     assert(s2.get_allocator() == Alloc());
  37     assert(s2.capacity() >= s2.size());
  38   }
  39   {
  40     S s2;
  41     s2 = sv;
  42     LIBCPP_ASSERT(s2.__invariants());
  43     assert(s2.size() == sv.size());
  44     assert(T::compare(s2.data(), sv.data(), sv.size()) == 0);
  45     assert(s2.get_allocator() == Alloc());
  46     assert(s2.capacity() >= s2.size());
  47   }
  48 }
  49
  50 template <class Alloc, class CharT>
  51 TEST_CONSTEXPR_CXX20 void test(std::basic_string_view<CharT> sv, const Alloc& a) {
  52   typedef std::basic_string<CharT, std::char_traits<CharT>, Alloc> S;
  53   typedef typename S::traits_type T;
  54   {
  55     S s2(sv, a);
  56     LIBCPP_ASSERT(s2.__invariants());
  57     assert(s2.size() == sv.size());
  58     assert(T::compare(s2.data(), sv.data(), sv.size()) == 0);
  59     assert(s2.get_allocator() == a);
  60     assert(s2.capacity() >= s2.size());
  61   }
  62   {
  63     S s2(a);
  64     s2 = sv;
  65     LIBCPP_ASSERT(s2.__invariants());
  66     assert(s2.size() == sv.size());
  67     assert(T::compare(s2.data(), sv.data(), sv.size()) == 0);
  68     assert(s2.get_allocator() == a);
  69     assert(s2.capacity() >= s2.size());
  70   }
  71 }
  72
  73 template <class Alloc>
  74 TEST_CONSTEXPR_CXX20 void test_string(const Alloc& a) {
  75   typedef std::basic_string_view<char, std::char_traits<char> > SV;
  76
  77   test<Alloc>(SV(""));
  78   test<Alloc>(SV(""), Alloc(a));
  79
  80   test<Alloc>(SV("1"));
  81   test<Alloc>(SV("1"), Alloc(a));
  82
  83   test<Alloc>(SV("1234567980"));
  84   test<Alloc>(SV("1234567980"), Alloc(a));
  85
  86   test<Alloc>(SV("123456798012345679801234567980123456798012345679801234567980"));
  87   test<Alloc>(SV("123456798012345679801234567980123456798012345679801234567980"), Alloc(a));
  88 }
  89
  90 TEST_CONSTEXPR_CXX20 bool test() {
  91   test_string(std::allocator<char>());
  92   test_string(test_allocator<char>());
  93   test_string(test_allocator<char>(2));
  94 #if TEST_STD_VER >= 11
  95   test_string(min_allocator<char>());
  96 #endif
  97
  98   return true;
  99 }
 100
 101 int main(int, char**) {
 102   test();
 103 #if TEST_STD_VER > 17
 104   static_assert(test());
 105 #endif
 106
 107   return 0;
 108 }