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
28namespace boost {
29namespace unit_test {
30
31class lazy_ostream {
32public:
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; }
44protected:
45 explicit lazy_ostream( bool p_empty = true ) : m_empty( p_empty ) {}
46
47private:
48 // Data members
49 bool m_empty;
50};
51
52//____________________________________________________________________________//
53
54template<typename PrevType, typename T, typename StorageT=T const&>
55class lazy_ostream_impl : public lazy_ostream {
56public:
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 }
68private:
69 // Data members
70 PrevType const& m_prev;
71 StorageT m_value;
72};
73
74//____________________________________________________________________________//
75
76template<typename T>
77inline lazy_ostream_impl<lazy_ostream,T>
78operator<<( lazy_ostream const& prev, T const& v )
79{
80 return lazy_ostream_impl<lazy_ostream,T>( prev, v );
81}
82
83//____________________________________________________________________________//
84
85template<typename PrevPrevType, typename TPrev, typename T>
86inline lazy_ostream_impl<lazy_ostream_impl<PrevPrevType,TPrev>,T>
87operator<<( 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
97template<typename R,typename S>
98inline lazy_ostream_impl<lazy_ostream,R& (BOOST_TEST_CALL_DECL *)(S&),R& (BOOST_TEST_CALL_DECL *)(S&)>
99operator<<( 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
108template<typename PrevPrevType, typename TPrev,typename R,typename S>
109inline lazy_ostream_impl<lazy_ostream_impl<PrevPrevType,TPrev>,R& (BOOST_TEST_CALL_DECL *)(S&),R& (BOOST_TEST_CALL_DECL *)(S&)>
110operator<<( 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
129