libstdc++-v3/testsuite/20_util/weak_ptr/observers/owner_before.cc

   1 // { dg-do run { target c++11 } }
   2 // { dg-require-effective-target hosted }
   3
   4 // Copyright (C) 2008-2024 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 // 20.8.13.3 Template class weak_ptr [util.smartptr.weak]
  22
  23 #include <memory>
  24 #include <testsuite_hooks.h>
  25
  26 struct A { };
  27 struct B { };
  28
  29 // 20.6.6.3.5 weak_ptr observers [util.smartptr.weak.obs]
  30
  31 void
  32 test01()
  33 {
  34   // test empty weak_ptrs compare equivalent
  35   std::weak_ptr<A> p1;
  36   std::weak_ptr<B> p2;
  37   VERIFY( !p1.owner_before(p2) && !p2.owner_before(p1) );
  38
  39   std::shared_ptr<B> p3;
  40   VERIFY( !p1.owner_before(p3) && !p3.owner_before(p1) );
  41
  42   static_assert( noexcept(p1.owner_before(p1)), "" );
  43   static_assert( noexcept(p1.owner_before(p2)), "" );
  44   static_assert( noexcept(p1.owner_before(p3)), "" );
  45   static_assert( noexcept(p2.owner_before(p1)), "" );
  46 }
  47
  48
  49 void
  50 test02()
  51 {
  52   std::shared_ptr<A> a0;
  53   std::weak_ptr<A> w0(a0);
  54
  55   std::shared_ptr<A> a1(new A);
  56   std::weak_ptr<A> w1(a1);
  57   VERIFY( !a1.owner_before(w1) && !w1.owner_before(a1) );
  58
  59   VERIFY( w1.owner_before(w0) || w0.owner_before(w1) );
  60   VERIFY( !(w1.owner_before(w0) && w0.owner_before(w1)) );
  61
  62   VERIFY( w1.owner_before(a0) || a0.owner_before(w1) );
  63   VERIFY( !(w1.owner_before(a0) && a0.owner_before(w1)) );
  64
  65   std::shared_ptr<B> b1(new B);
  66   VERIFY( w1.owner_before(b1) || b1.owner_before(w1) );
  67 }
  68
  69 int
  70 main()
  71 {
  72   test01();
  73   test02();
  74   return 0;
  75 }