libcxx/test/std/strings/basic.string/string.capacity/reserve.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 // void reserve(); // Deprecated in C++20.
  12
  13 // ADDITIONAL_COMPILE_FLAGS: -D_LIBCPP_DISABLE_DEPRECATION_WARNINGS
  14
  15 #include <string>
  16 #include <stdexcept>
  17 #include <cassert>
  18
  19 #include "test_macros.h"
  20 #include "min_allocator.h"
  21
  22 template <class S>
  23 void
  24 test(typename S::size_type min_cap, typename S::size_type erased_index)
  25 {
  26     S s(min_cap, 'a');
  27     s.erase(erased_index);
  28     assert(s.size() == erased_index);
  29     assert(s.capacity() >= min_cap); // Check that we really have at least this capacity.
  30
  31     typename S::size_type old_cap = s.capacity();
  32     S s0 = s;
  33     s.reserve();
  34     LIBCPP_ASSERT(s.__invariants());
  35     assert(s == s0);
  36     assert(s.capacity() <= old_cap);
  37     assert(s.capacity() >= s.size());
  38 }
  39
  40 int main(int, char**)
  41 {
  42     {
  43     typedef std::string S;
  44     {
  45     test<S>(0, 0);
  46     test<S>(10, 5);
  47     test<S>(100, 50);
  48     }
  49     }
  50 #if TEST_STD_VER >= 11
  51     {
  52     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
  53     {
  54     test<S>(0, 0);
  55     test<S>(10, 5);
  56     test<S>(100, 50);
  57     }
  58     }
  59 #endif
  60
  61   return 0;
  62 }