ceph/src/boost/boost/test/utils/lazy_ostream.hpp

   1 //  (C) Copyright Gennadiy Rozental 2001.
   2 //  Distributed under the Boost Software License, Version 1.0.
   3 //  (See accompanying file LICENSE_1_0.txt or copy at
   4 //  http://www.boost.org/LICENSE_1_0.txt)
   5
   6 //  See http://www.boost.org/libs/test for the library home page.
   7 //
   8 //  Description : contains definition for all test tools in test toolbox
   9 // ***************************************************************************
  10
  11 #ifndef BOOST_TEST_UTILS_LAZY_OSTREAM_HPP
  12 #define BOOST_TEST_UTILS_LAZY_OSTREAM_HPP
  13
  14 // Boost.Test
  15 #include <boost/test/detail/config.hpp>
  16
  17 // STL
  18 #include <iosfwd>
  19
  20 #include <boost/test/detail/suppress_warnings.hpp>
  21
  22 //____________________________________________________________________________//
  23
  24 // ************************************************************************** //
  25 // **************                  lazy_ostream                ************** //
  26 // ************************************************************************** //
  27
  28 namespace boost {
  29 namespace unit_test {
  30
  31 class lazy_ostream {
  32 public:
  33     virtual                 ~lazy_ostream()                                         {}
  34
  35     static lazy_ostream&    instance()                                              { static lazy_ostream inst; return inst; }
  36
  37     friend std::ostream&    operator<<( std::ostream& ostr, lazy_ostream const& o ) { return o( ostr ); }
  38
  39     // access method
  40     bool                    empty() const                                           { return m_empty; }
  41
  42     // actual printing interface; to be accessed only by this class and children
  43     virtual std::ostream&   operator()( std::ostream& ostr ) const                  { return ostr; }
  44 protected:
  45     explicit                lazy_ostream( bool p_empty = true ) : m_empty( p_empty )    {}
  46
  47 private:
  48     // Data members
  49     bool                    m_empty;
  50 };
  51
  52 //____________________________________________________________________________//
  53
  54 template<typename PrevType, typename T, typename StorageT=T const&>
  55 class lazy_ostream_impl : public lazy_ostream {
  56 public:
  57     lazy_ostream_impl( PrevType const& prev, T const& value )
  58     : lazy_ostream( false )
  59     , m_prev( prev )
  60     , m_value( value )
  61     {
  62     }
  63
  64     virtual std::ostream&   operator()( std::ostream& ostr ) const
  65     {
  66         return m_prev(ostr) << m_value;
  67     }
  68 private:
  69     // Data members
  70     PrevType const&         m_prev;
  71     StorageT                m_value;
  72 };
  73
  74 //____________________________________________________________________________//
  75
  76 template<typename T>
  77 inline lazy_ostream_impl<lazy_ostream,T>
  78 operator<<( lazy_ostream const& prev, T const& v )
  79 {
  80     return lazy_ostream_impl<lazy_ostream,T>( prev, v );
  81 }
  82
  83 //____________________________________________________________________________//
  84
  85 template<typename PrevPrevType, typename TPrev, typename T>
  86 inline lazy_ostream_impl<lazy_ostream_impl<PrevPrevType,TPrev>,T>
  87 operator<<( lazy_ostream_impl<PrevPrevType,TPrev> const& prev, T const& v )
  88 {
  89     typedef lazy_ostream_impl<PrevPrevType,TPrev> PrevType;
  90     return lazy_ostream_impl<PrevType,T>( prev, v );
  91 }
  92
  93 //____________________________________________________________________________//
  94
  95 #if BOOST_TEST_USE_STD_LOCALE
  96
  97 template<typename R,typename S>
  98 inline lazy_ostream_impl<lazy_ostream,R& (BOOST_TEST_CALL_DECL *)(S&),R& (BOOST_TEST_CALL_DECL *)(S&)>
  99 operator<<( lazy_ostream const& prev, R& (BOOST_TEST_CALL_DECL *man)(S&) )
 100 {
 101     typedef R& (BOOST_TEST_CALL_DECL * ManipType)(S&);
 102
 103     return lazy_ostream_impl<lazy_ostream,ManipType,ManipType>( prev, man );
 104 }
 105
 106 //____________________________________________________________________________//
 107
 108 template<typename PrevPrevType, typename TPrev,typename R,typename S>
 109 inline lazy_ostream_impl<lazy_ostream_impl<PrevPrevType,TPrev>,R& (BOOST_TEST_CALL_DECL *)(S&),R& (BOOST_TEST_CALL_DECL *)(S&)>
 110 operator<<( lazy_ostream_impl<PrevPrevType,TPrev> const& prev, R& (BOOST_TEST_CALL_DECL *man)(S&) )
 111 {
 112     typedef R& (BOOST_TEST_CALL_DECL * ManipType)(S&);
 113
 114     return lazy_ostream_impl<lazy_ostream_impl<PrevPrevType,TPrev>,ManipType,ManipType>( prev, man );
 115 }
 116
 117 //____________________________________________________________________________//
 118
 119 #endif
 120
 121 #define BOOST_TEST_LAZY_MSG( M ) (::boost::unit_test::lazy_ostream::instance() << M)
 122
 123 } // namespace unit_test
 124 } // namespace boost
 125
 126 #include <boost/test/detail/enable_warnings.hpp>
 127
 128 #endif // BOOST_TEST_UTILS_LAZY_OSTREAM_HPP