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:
~lazy_ostream()33 virtual ~lazy_ostream() {}
34
instance()35 static lazy_ostream& instance() { static lazy_ostream inst; return inst; }
36
operator <<(std::ostream & ostr,lazy_ostream const & o)37 friend std::ostream& operator<<( std::ostream& ostr, lazy_ostream const& o ) { return o( ostr ); }
38
39 // access method
empty() const40 bool empty() const { return m_empty; }
41
42 // actual printing interface; to be accessed only by this class and children
operator ()(std::ostream & ostr) const43 virtual std::ostream& operator()( std::ostream& ostr ) const { return ostr; }
44 protected:
lazy_ostream(bool p_empty=true)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:
lazy_ostream_impl(PrevType const & prev,T const & value)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
operator ()(std::ostream & ostr) const64 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>
operator <<(lazy_ostream const & prev,T const & v)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>
operator <<(lazy_ostream_impl<PrevPrevType,TPrev> const & prev,T const & v)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&)>
operator <<(lazy_ostream const & prev,R & (BOOST_TEST_CALL_DECL * man)(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&)>
operator <<(lazy_ostream_impl<PrevPrevType,TPrev> const & prev,R & (BOOST_TEST_CALL_DECL * man)(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
129