ceph/src/boost/libs/smart_ptr/test/make_shared_move_emulation_test.cpp

   1 // make_shared_move_emulation_test.cpp - a test of make_shared
   2 //   semi-perfect forwarding of constructor arguments when using a C++03
   3 //   compiler with move emulation.
   4 //   Note the "semi": it means moving temporaries (real r-values) doesn't work.
   5 //
   6 // Copyright 2016 Giel van Schijndel
   7 //
   8 // Distributed under the Boost Software License, Version 1.0.
   9 // See accompanying file LICENSE_1_0.txt or copy at
  10 // http://www.boost.org/LICENSE_1_0.txt
  11
  12 #include <boost/core/lightweight_test.hpp>
  13 #include <boost/make_shared.hpp>
  14 #include <boost/move/core.hpp>
  15 #include <boost/move/utility_core.hpp>
  16 #include <boost/shared_ptr.hpp>
  17
  18 class movearg
  19 {
  20 private:
  21     BOOST_MOVABLE_BUT_NOT_COPYABLE(movearg)
  22 public:
  23     movearg()
  24     {}
  25     movearg(BOOST_RV_REF(movearg))
  26     {}
  27     movearg& operator=(BOOST_RV_REF(movearg))
  28     {
  29         return *this;
  30     }
  31 };
  32
  33 class ByVal
  34 {
  35 public:
  36     ByVal(movearg) {}
  37 };
  38
  39 class ByRef
  40 {
  41 public:
  42     enum constructor_id
  43     {
  44         move_constructor,
  45         const_ref_constructor
  46     };
  47
  48     ByRef(BOOST_RV_REF(movearg)): constructed_by_(move_constructor)
  49     {}
  50     ByRef(const movearg &arg): constructed_by_(const_ref_constructor)
  51     {}
  52
  53     constructor_id constructed_by_;
  54 };
  55
  56 int main()
  57 {
  58     {
  59         movearg a;
  60         boost::shared_ptr< ByVal > x = boost::make_shared< ByVal >(boost::move(a));
  61     }
  62     {
  63         movearg a;
  64         boost::shared_ptr< ByRef > x = boost::make_shared< ByRef >(boost::move(a));
  65         BOOST_TEST( x->constructed_by_ == ByRef::move_constructor);
  66     }
  67 #if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
  68     {
  69         boost::shared_ptr< ByVal > x = boost::make_shared< ByVal >(movearg());
  70         boost::shared_ptr< ByRef > y = boost::make_shared< ByRef >(movearg());
  71         BOOST_TEST( y->constructed_by_ == ByRef::move_constructor);
  72     }
  73 #endif // !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
  74     {
  75         const movearg ca;
  76         boost::shared_ptr< ByRef > x = boost::make_shared< ByRef >(ca);
  77         BOOST_TEST( x->constructed_by_ == ByRef::const_ref_constructor);
  78     }
  79
  80     return boost::report_errors();
  81 }