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 test(typename S::size_type min_cap, typename S::size_type erased_index) {
  24   S s(min_cap, 'a');
  25   s.erase(erased_index);
  26   assert(s.size() == erased_index);
  27   assert(s.capacity() >= min_cap); // Check that we really have at least this capacity.
  28
  29   typename S::size_type old_cap = s.capacity();
  30   S s0                          = s;
  31   s.reserve();
  32   LIBCPP_ASSERT(s.__invariants());
  33   assert(s == s0);
  34   assert(s.capacity() <= old_cap);
  35   assert(s.capacity() >= s.size());
  36 }
  37
  38 template <class S>
  39 void test_string() {
  40   test<S>(0, 0);
  41   test<S>(10, 5);
  42   test<S>(100, 50);
  43 }
  44
  45 bool test() {
  46   test_string<std::string>();
  47 #if TEST_STD_VER >= 11
  48   test_string<std::basic_string<char, std::char_traits<char>, min_allocator<char>>>();
  49 #endif
  50
  51   return true;
  52 }
  53
  54 int main(int, char**) {
  55   test();
  56
  57   return 0;
  58 }