libstdc++-v3/testsuite/21_strings/basic_string/capacity/char/18654.cc

   1 // 2004-11-29  Paolo Carlini  <pcarlini@suse.de>
   2
   3 // Copyright (C) 2004-2021 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 // 21.3.3 string capacity
  21
  22 // { dg-options "-DMAX_SIZE=16" { target simulator } }
  23
  24 #ifndef MAX_SIZE
  25 #define MAX_SIZE 20
  26 #endif
  27
  28 #include <string>
  29 #include <testsuite_hooks.h>
  30
  31 // libstdc++/18654
  32 void test01()
  33 {
  34   using namespace std;
  35
  36   typedef string::size_type size_type;
  37
  38 #if _GLIBCXX_USE_CXX11_ABI
  39   // Can't shrink below small string size.
  40   const size_type minsize = string().capacity() + 1;
  41 #else
  42   // Exact shrink-to-size and shrink-to-fit
  43   const size_type minsize = 2 << 0;
  44 #endif
  45   const size_type maxsize = 2 << MAX_SIZE;
  46   for (size_type i = minsize; i <= maxsize; i *= 2)
  47     {
  48       string str(i, 'x');
  49       str.reserve(3 * i);
  50       const size_type cap = str.capacity();
  51       VERIFY( cap >= 3 * i );
  52
  53       str.reserve(2 * i);
  54       VERIFY( str.capacity() == cap );
  55
  56 #if __cplusplus <= 201703L
  57       str.reserve();
  58 #else
  59       str.shrink_to_fit(); // reserve is deprecated in C++20
  60 #endif
  61       VERIFY( str.capacity() == i );
  62     }
  63 }
  64
  65 int main()
  66 {
  67   test01();
  68   return 0;
  69 }