libcxx/test/std/strings/basic.string/string.cons/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 // <string>
  10
  11 // explicit basic_string(const Allocator& a = Allocator()); // constexpr since C++20
  12
  13 #include <string>
  14 #include <cassert>
  15
  16 #include "test_macros.h"
  17 #include "test_allocator.h"
  18 #include "min_allocator.h"
  19
  20 template <class S>
  21 TEST_CONSTEXPR_CXX20 void test() {
  22   {
  23 #if TEST_STD_VER > 14
  24     static_assert((noexcept(S{})), "");
  25 #elif TEST_STD_VER >= 11
  26     static_assert((noexcept(S()) == noexcept(typename S::allocator_type())), "");
  27 #endif
  28     S s;
  29     LIBCPP_ASSERT(s.__invariants());
  30     assert(s.data());
  31     assert(s.size() == 0);
  32     assert(s.capacity() >= s.size());
  33     assert(s.get_allocator() == typename S::allocator_type());
  34   }
  35   {
  36 #if TEST_STD_VER > 14
  37     static_assert((noexcept(S{typename S::allocator_type{}})), "");
  38 #elif TEST_STD_VER >= 11
  39     static_assert((noexcept(S(typename S::allocator_type())) ==
  40                    std::is_nothrow_copy_constructible<typename S::allocator_type>::value),
  41                   "");
  42 #endif
  43     S s(typename S::allocator_type(5));
  44     LIBCPP_ASSERT(s.__invariants());
  45     assert(s.data());
  46     assert(s.size() == 0);
  47     assert(s.capacity() >= s.size());
  48     assert(s.get_allocator() == typename S::allocator_type(5));
  49   }
  50 }
  51
  52 #if TEST_STD_VER >= 11
  53
  54 template <class S>
  55 TEST_CONSTEXPR_CXX20 void test2() {
  56   {
  57 #  if TEST_STD_VER > 14
  58     static_assert((noexcept(S{})), "");
  59 #  elif TEST_STD_VER >= 11
  60     static_assert((noexcept(S()) == noexcept(typename S::allocator_type())), "");
  61 #  endif
  62     S s;
  63     LIBCPP_ASSERT(s.__invariants());
  64     assert(s.data());
  65     assert(s.size() == 0);
  66     assert(s.capacity() >= s.size());
  67     assert(s.get_allocator() == typename S::allocator_type());
  68   }
  69   {
  70 #  if TEST_STD_VER > 14
  71     static_assert((noexcept(S{typename S::allocator_type{}})), "");
  72 #  elif TEST_STD_VER >= 11
  73     static_assert((noexcept(S(typename S::allocator_type())) ==
  74                    std::is_nothrow_copy_constructible<typename S::allocator_type>::value),
  75                   "");
  76 #  endif
  77     S s(typename S::allocator_type{});
  78     LIBCPP_ASSERT(s.__invariants());
  79     assert(s.data());
  80     assert(s.size() == 0);
  81     assert(s.capacity() >= s.size());
  82     assert(s.get_allocator() == typename S::allocator_type());
  83   }
  84 }
  85
  86 #endif
  87
  88 TEST_CONSTEXPR_CXX20 bool test() {
  89   test<std::basic_string<char, std::char_traits<char>, test_allocator<char> > >();
  90 #if TEST_STD_VER >= 11
  91   test2<std::basic_string<char, std::char_traits<char>, min_allocator<char> > >();
  92   test2<std::basic_string<char, std::char_traits<char>, explicit_allocator<char> > >();
  93 #endif
  94
  95   return true;
  96 }
  97
  98 int main(int, char**) {
  99   test();
 100 #if TEST_STD_VER > 17
 101   static_assert(test());
 102 #endif
 103
 104   return 0;
 105 }