00001 // Copyright 2005, Google Inc. 00002 // All rights reserved. 00003 // 00004 // Redistribution and use in source and binary forms, with or without 00005 // modification, are permitted provided that the following conditions are 00006 // met: 00007 // 00008 // * Redistributions of source code must retain the above copyright 00009 // notice, this list of conditions and the following disclaimer. 00010 // * Redistributions in binary form must reproduce the above 00011 // copyright notice, this list of conditions and the following disclaimer 00012 // in the documentation and/or other materials provided with the 00013 // distribution. 00014 // * Neither the name of Google Inc. nor the names of its 00015 // contributors may be used to endorse or promote products derived from 00016 // this software without specific prior written permission. 00017 // 00018 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 00019 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 00020 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 00021 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 00022 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 00023 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 00024 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 00025 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 00026 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 00027 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 00028 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 00029 // 00030 // Author: wan@google.com (Zhanyong Wan) 00031 // 00032 // The Google C++ Testing Framework (Google Test) 00033 // 00034 // This header file defines the Message class. 00035 // 00036 // IMPORTANT NOTE: Due to limitation of the C++ language, we have to 00037 // leave some internal implementation details in this header file. 00038 // They are clearly marked by comments like this: 00039 // 00040 // // INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM. 00041 // 00042 // Such code is NOT meant to be used by a user directly, and is subject 00043 // to CHANGE WITHOUT NOTICE. Therefore DO NOT DEPEND ON IT in a user 00044 // program! 00045 00046 #ifndef GTEST_INCLUDE_GTEST_GTEST_MESSAGE_H_ 00047 #define GTEST_INCLUDE_GTEST_GTEST_MESSAGE_H_ 00048 00049 #include <limits> 00050 00051 #include "gtest/internal/gtest-port.h" 00052 00053 // Ensures that there is at least one operator<< in the global namespace. 00054 // See Message& operator<<(...) below for why. 00055 void operator<<(const testing::internal::Secret&, int); 00056 00057 namespace testing { 00058 00059 // The Message class works like an ostream repeater. 00060 // 00061 // Typical usage: 00062 // 00063 // 1. You stream a bunch of values to a Message object. 00064 // It will remember the text in a stringstream. 00065 // 2. Then you stream the Message object to an ostream. 00066 // This causes the text in the Message to be streamed 00067 // to the ostream. 00068 // 00069 // For example; 00070 // 00071 // testing::Message foo; 00072 // foo << 1 << " != " << 2; 00073 // std::cout << foo; 00074 // 00075 // will print "1 != 2". 00076 // 00077 // Message is not intended to be inherited from. In particular, its 00078 // destructor is not virtual. 00079 // 00080 // Note that stringstream behaves differently in gcc and in MSVC. You 00081 // can stream a NULL char pointer to it in the former, but not in the 00082 // latter (it causes an access violation if you do). The Message 00083 // class hides this difference by treating a NULL char pointer as 00084 // "(null)". 00085 class GTEST_API_ Message { 00086 private: 00087 // The type of basic IO manipulators (endl, ends, and flush) for 00088 // narrow streams. 00089 typedef std::ostream& (*BasicNarrowIoManip)(std::ostream&); 00090 00091 public: 00092 // Constructs an empty Message. 00093 Message(); 00094 00095 // Copy constructor. 00096 Message(const Message& msg) : ss_(new ::std::stringstream) { // NOLINT 00097 *ss_ << msg.GetString(); 00098 } 00099 00100 // Constructs a Message from a C-string. 00101 explicit Message(const char* str) : ss_(new ::std::stringstream) { 00102 *ss_ << str; 00103 } 00104 00105 #if GTEST_OS_SYMBIAN 00106 // Streams a value (either a pointer or not) to this object. 00107 template <typename T> 00108 inline Message& operator <<(const T& value) { 00109 StreamHelper(typename internal::is_pointer<T>::type(), value); 00110 return *this; 00111 } 00112 #else 00113 // Streams a non-pointer value to this object. 00114 template <typename T> 00115 inline Message& operator <<(const T& val) { 00116 // Some libraries overload << for STL containers. These 00117 // overloads are defined in the global namespace instead of ::std. 00118 // 00119 // C++'s symbol lookup rule (i.e. Koenig lookup) says that these 00120 // overloads are visible in either the std namespace or the global 00121 // namespace, but not other namespaces, including the testing 00122 // namespace which Google Test's Message class is in. 00123 // 00124 // To allow STL containers (and other types that has a << operator 00125 // defined in the global namespace) to be used in Google Test 00126 // assertions, testing::Message must access the custom << operator 00127 // from the global namespace. With this using declaration, 00128 // overloads of << defined in the global namespace and those 00129 // visible via Koenig lookup are both exposed in this function. 00130 using ::operator <<; 00131 *ss_ << val; 00132 return *this; 00133 } 00134 00135 // Streams a pointer value to this object. 00136 // 00137 // This function is an overload of the previous one. When you 00138 // stream a pointer to a Message, this definition will be used as it 00139 // is more specialized. (The C++ Standard, section 00140 // [temp.func.order].) If you stream a non-pointer, then the 00141 // previous definition will be used. 00142 // 00143 // The reason for this overload is that streaming a NULL pointer to 00144 // ostream is undefined behavior. Depending on the compiler, you 00145 // may get "0", "(nil)", "(null)", or an access violation. To 00146 // ensure consistent result across compilers, we always treat NULL 00147 // as "(null)". 00148 template <typename T> 00149 inline Message& operator <<(T* const& pointer) { // NOLINT 00150 if (pointer == NULL) { 00151 *ss_ << "(null)"; 00152 } else { 00153 *ss_ << pointer; 00154 } 00155 return *this; 00156 } 00157 #endif // GTEST_OS_SYMBIAN 00158 00159 // Since the basic IO manipulators are overloaded for both narrow 00160 // and wide streams, we have to provide this specialized definition 00161 // of operator <<, even though its body is the same as the 00162 // templatized version above. Without this definition, streaming 00163 // endl or other basic IO manipulators to Message will confuse the 00164 // compiler. 00165 Message& operator <<(BasicNarrowIoManip val) { 00166 *ss_ << val; 00167 return *this; 00168 } 00169 00170 // Instead of 1/0, we want to see true/false for bool values. 00171 Message& operator <<(bool b) { 00172 return *this << (b ? "true" : "false"); 00173 } 00174 00175 // These two overloads allow streaming a wide C string to a Message 00176 // using the UTF-8 encoding. 00177 Message& operator <<(const wchar_t* wide_c_str); 00178 Message& operator <<(wchar_t* wide_c_str); 00179 00180 #if GTEST_HAS_STD_WSTRING 00181 // Converts the given wide string to a narrow string using the UTF-8 00182 // encoding, and streams the result to this Message object. 00183 Message& operator <<(const ::std::wstring& wstr); 00184 #endif // GTEST_HAS_STD_WSTRING 00185 00186 #if GTEST_HAS_GLOBAL_WSTRING 00187 // Converts the given wide string to a narrow string using the UTF-8 00188 // encoding, and streams the result to this Message object. 00189 Message& operator <<(const ::wstring& wstr); 00190 #endif // GTEST_HAS_GLOBAL_WSTRING 00191 00192 // Gets the text streamed to this object so far as an std::string. 00193 // Each '\0' character in the buffer is replaced with "\\0". 00194 // 00195 // INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM. 00196 std::string GetString() const; 00197 00198 private: 00199 00200 #if GTEST_OS_SYMBIAN 00201 // These are needed as the Nokia Symbian Compiler cannot decide between 00202 // const T& and const T* in a function template. The Nokia compiler _can_ 00203 // decide between class template specializations for T and T*, so a 00204 // tr1::type_traits-like is_pointer works, and we can overload on that. 00205 template <typename T> 00206 inline void StreamHelper(internal::true_type /*is_pointer*/, T* pointer) { 00207 if (pointer == NULL) { 00208 *ss_ << "(null)"; 00209 } else { 00210 *ss_ << pointer; 00211 } 00212 } 00213 template <typename T> 00214 inline void StreamHelper(internal::false_type /*is_pointer*/, 00215 const T& value) { 00216 // See the comments in Message& operator <<(const T&) above for why 00217 // we need this using statement. 00218 using ::operator <<; 00219 *ss_ << value; 00220 } 00221 #endif // GTEST_OS_SYMBIAN 00222 00223 // We'll hold the text streamed to this object here. 00224 const internal::scoped_ptr< ::std::stringstream> ss_; 00225 00226 // We declare (but don't implement) this to prevent the compiler 00227 // from implementing the assignment operator. 00228 void operator=(const Message&); 00229 }; 00230 00231 // Streams a Message to an ostream. 00232 inline std::ostream& operator <<(std::ostream& os, const Message& sb) { 00233 return os << sb.GetString(); 00234 } 00235 00236 namespace internal { 00237 00238 // Converts a streamable value to an std::string. A NULL pointer is 00239 // converted to "(null)". When the input value is a ::string, 00240 // ::std::string, ::wstring, or ::std::wstring object, each NUL 00241 // character in it is replaced with "\\0". 00242 template <typename T> 00243 std::string StreamableToString(const T& streamable) { 00244 return (Message() << streamable).GetString(); 00245 } 00246 00247 } // namespace internal 00248 } // namespace testing 00249 00250 #endif // GTEST_INCLUDE_GTEST_GTEST_MESSAGE_H_