libstdc++-v3/testsuite/21_strings/basic_string/cons/char/8.cc

   1 // Copyright (C) 2016-2020 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-options "-O0" }
  19 // { dg-do run { target c++11 } }
  20
  21 #include <string>
  22 #include <testsuite_hooks.h>
  23
  24 struct TestBaseObjCtor : std::string
  25 {
  26   template<typename... Args>
  27     TestBaseObjCtor(Args&&... args)
  28     : std::string(std::forward<Args>(args)...)
  29     { }
  30 };
  31
  32 template<typename... Args>
  33 std::size_t
  34 construct(Args&&... args)
  35 {
  36   // Use static_cast<Args> to produce either an lvalue or prvalue,
  37   // so args... not left in moved-from state and can be reused below:
  38   TestBaseObjCtor as_base_obj( static_cast<Args>(args)... );
  39
  40   std::string as_complete_obj( std::forward<Args>(args)... );
  41
  42   return as_complete_obj.length();
  43 }
  44
  45 void
  46 test01()
  47 {
  48   using string = std::string;
  49   using list = std::initializer_list<string::value_type>;
  50
  51   const std::string lvalue = "lvalue";
  52   std::allocator<char> alloc;
  53
  54   // test all valid combinations of arguments:
  55   VERIFY( construct( ) == 0 );
  56   VERIFY( construct( alloc ) == 0 );
  57   VERIFY( construct( lvalue ) == 6 );
  58   VERIFY( construct( string{"rvalue"} ) == 6 );
  59   VERIFY( construct( lvalue, 2 ) == 4 );
  60   VERIFY( construct( lvalue, 2, alloc ) == 4 );
  61   VERIFY( construct( lvalue, 2, 3 ) == 3 );
  62   VERIFY( construct( lvalue, 2, 3, alloc ) == 3 );
  63   VERIFY( construct( "C string", 4 ) == 4 );
  64   VERIFY( construct( "C string", 4, alloc ) == 4 );
  65   VERIFY( construct( "C string" ) == 8 );
  66   VERIFY( construct( "C string and alloc", alloc ) == 18 );
  67   VERIFY( construct( 5, ' ' ) == 5 );
  68   VERIFY( construct( 5, ' ', alloc ) == 5 );
  69   VERIFY( construct( lvalue.begin(), lvalue.end() ) == 6 );
  70   VERIFY( construct( lvalue.begin(), lvalue.end(), alloc ) == 6 );
  71   VERIFY( construct( list{ 'l' , 'i' , 's', 't' } ) == 4 );
  72   VERIFY( construct( list{ 'l', 'i', 's', 't' }, alloc ) == 4 );
  73   VERIFY( construct( lvalue, alloc ) == 6 );
  74   VERIFY( construct( string{"rvalue"}, alloc ) == 6 );
  75 }
  76
  77 int
  78 main()
  79 {
  80   test01();
  81 }