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 //  File        : $RCSfile$
9 //
10 //  Version     : $Revision: 74248 $
11 //
12 //  Description : defines level of indiration facilitating workarounds for non printable types
13 // ***************************************************************************
14 
15 #ifndef BOOST_TEST_TOOLS_IMPL_COMMON_HPP_012705GER
16 #define BOOST_TEST_TOOLS_IMPL_COMMON_HPP_012705GER
17 
18 // Boost.Test
19 #include <boost/test/detail/config.hpp>
20 #include <boost/test/detail/global_typedef.hpp>
21 
22 // Boost
23 #include <boost/mpl/or.hpp>
24 #include <boost/static_assert.hpp>
25 #include <boost/type_traits/is_array.hpp>
26 #include <boost/type_traits/is_function.hpp>
27 #include <boost/type_traits/is_abstract.hpp>
28 #include <boost/type_traits/has_left_shift.hpp>
29 
30 #include <ios>
31 #include <iostream>
32 #include <limits>
33 
34 #if !defined(BOOST_NO_CXX11_NULLPTR)
35 #include <cstddef>
36 #endif
37 
38 #include <boost/test/detail/suppress_warnings.hpp>
39 
40 //____________________________________________________________________________//
41 
42 namespace boost {
43 namespace test_tools {
44 namespace tt_detail {
45 
46 // ************************************************************************** //
47 // **************          boost_test_print_type               ************** //
48 // ************************************************************************** //
49 
50     namespace impl {
51         template <class T>
boost_test_print_type(std::ostream & ostr,T const & t)52         std::ostream& boost_test_print_type(std::ostream& ostr, T const& t) {
53             BOOST_STATIC_ASSERT_MSG( (boost::has_left_shift<std::ostream,T>::value),
54                                     "Type has to implement operator<< to be printable");
55             ostr << t;
56             return ostr;
57         }
58 
59         struct boost_test_print_type_impl {
60             template <class R>
operator ()boost::test_tools::tt_detail::impl::boost_test_print_type_impl61             std::ostream& operator()(std::ostream& ostr, R const& r) const {
62                 return boost_test_print_type(ostr, r);
63             }
64         };
65     }
66 
67     // To avoid ODR violations, see N4381
68     template <class T> struct static_const { static const T value; };
69     template <class T> const T static_const<T>::value = T();
70 
71     namespace {
72         static const impl::boost_test_print_type_impl& boost_test_print_type =
73             static_const<impl::boost_test_print_type_impl>::value;
74     }
75 
76 
77 // ************************************************************************** //
78 // **************                print_log_value               ************** //
79 // ************************************************************************** //
80 
81 template<typename T>
82 struct print_log_value {
operator ()boost::test_tools::tt_detail::print_log_value83     void    operator()( std::ostream& ostr, T const& t )
84     {
85         typedef typename mpl::or_<is_array<T>,is_function<T>,is_abstract<T> >::type cant_use_nl;
86 
87         std::streamsize old_precision = set_precision( ostr, cant_use_nl() );
88 
89         //ostr << t;
90         using boost::test_tools::tt_detail::boost_test_print_type;
91         boost_test_print_type(ostr, t);
92 
93         if( old_precision != (std::streamsize)-1 )
94             ostr.precision( old_precision );
95     }
96 
set_precisionboost::test_tools::tt_detail::print_log_value97     std::streamsize set_precision( std::ostream& ostr, mpl::false_ )
98     {
99         if( std::numeric_limits<T>::is_specialized && std::numeric_limits<T>::radix == 2 )
100             return ostr.precision( 2 + std::numeric_limits<T>::digits * 301/1000 );
101         else if ( std::numeric_limits<T>::is_specialized && std::numeric_limits<T>::radix == 10 ) {
102 #ifdef BOOST_NO_CXX11_NUMERIC_LIMITS
103             // (was BOOST_NO_NUMERIC_LIMITS_LOWEST but now deprecated).
104             // No support for std::numeric_limits<double>::max_digits10,
105             // so guess that a couple of guard digits more than digits10 will display any difference.
106             return ostr.precision( 2 + std::numeric_limits<T>::digits10 );
107 #else
108             // std::numeric_limits<double>::max_digits10; IS supported.
109             // Any noisy or guard digits needed to display any difference are included in max_digits10.
110             return ostr.precision( std::numeric_limits<T>::max_digits10 );
111 #endif
112         }
113         // else if T is not specialized for std::numeric_limits<>,
114         // then will just get the default precision of 6 digits.
115         return (std::streamsize)-1;
116     }
117 
set_precisionboost::test_tools::tt_detail::print_log_value118     std::streamsize set_precision( std::ostream&, mpl::true_ ) { return (std::streamsize)-1; }
119 };
120 
121 //____________________________________________________________________________//
122 
123 #if BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x564))
124 template<typename T, std::size_t N >
125 struct print_log_value< T[N] > {
operator ()boost::test_tools::tt_detail::print_log_value126     void    operator()( std::ostream& ostr, T const* t )
127     {
128         ostr << t;
129     }
130 };
131 #endif
132 
133 //____________________________________________________________________________//
134 
135 template<>
136 struct BOOST_TEST_DECL print_log_value<bool> {
137     void    operator()( std::ostream& ostr, bool t );
138 };
139 
140 //____________________________________________________________________________//
141 
142 template<>
143 struct BOOST_TEST_DECL print_log_value<char> {
144     void    operator()( std::ostream& ostr, char t );
145 };
146 
147 //____________________________________________________________________________//
148 
149 template<>
150 struct BOOST_TEST_DECL print_log_value<unsigned char> {
151     void    operator()( std::ostream& ostr, unsigned char t );
152 };
153 
154 //____________________________________________________________________________//
155 
156 template<>
157 struct BOOST_TEST_DECL print_log_value<char const*> {
158     void    operator()( std::ostream& ostr, char const* t );
159 };
160 
161 //____________________________________________________________________________//
162 
163 template<>
164 struct BOOST_TEST_DECL print_log_value<wchar_t const*> {
165     void    operator()( std::ostream& ostr, wchar_t const* t );
166 };
167 
168 #if !defined(BOOST_NO_CXX11_NULLPTR)
169 template<>
170 struct print_log_value<std::nullptr_t> {
171     // declaration and definition is here because of #12969 https://svn.boost.org/trac10/ticket/12969
operator ()boost::test_tools::tt_detail::print_log_value172     void    operator()( std::ostream& ostr, std::nullptr_t /*t*/ ) {
173         ostr << "nullptr";
174     }
175 };
176 #endif
177 
178 //____________________________________________________________________________//
179 
180 // ************************************************************************** //
181 // **************                 print_helper                 ************** //
182 // ************************************************************************** //
183 // Adds level of indirection to the output operation, allowing us to customize
184 // it for types that do not support operator << directly or for any other reason
185 
186 template<typename T>
187 struct print_helper_t {
print_helper_tboost::test_tools::tt_detail::print_helper_t188     explicit    print_helper_t( T const& t ) : m_t( t ) {}
189 
190     T const&    m_t;
191 };
192 
193 //____________________________________________________________________________//
194 
195 #if BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x564))
196 // Borland suffers premature pointer decay passing arrays by reference
197 template<typename T, std::size_t N >
198 struct print_helper_t< T[N] > {
print_helper_tboost::test_tools::tt_detail::print_helper_t199     explicit    print_helper_t( T const * t ) : m_t( t ) {}
200 
201     T const *   m_t;
202 };
203 #endif
204 
205 //____________________________________________________________________________//
206 
207 template<typename T>
208 inline print_helper_t<T>
print_helper(T const & t)209 print_helper( T const& t )
210 {
211     return print_helper_t<T>( t );
212 }
213 
214 //____________________________________________________________________________//
215 
216 template<typename T>
217 inline std::ostream&
operator <<(std::ostream & ostr,print_helper_t<T> const & ph)218 operator<<( std::ostream& ostr, print_helper_t<T> const& ph )
219 {
220     print_log_value<T>()( ostr, ph.m_t );
221 
222     return ostr;
223 }
224 
225 //____________________________________________________________________________//
226 
227 } // namespace tt_detail
228 
229 // ************************************************************************** //
230 // **************       BOOST_TEST_DONT_PRINT_LOG_VALUE        ************** //
231 // ************************************************************************** //
232 
233 #define BOOST_TEST_DONT_PRINT_LOG_VALUE( the_type )         \
234 namespace boost{ namespace test_tools{ namespace tt_detail{ \
235 template<>                                                  \
236 struct print_log_value<the_type > {                         \
237     void    operator()( std::ostream&, the_type const& ) {} \
238 };                                                          \
239 }}}                                                         \
240 /**/
241 
242 } // namespace test_tools
243 } // namespace boost
244 
245 #include <boost/test/detail/enable_warnings.hpp>
246 
247 #endif // BOOST_TEST_TOOLS_IMPL_COMMON_HPP_012705GER
248