Home | History | Annotate | Download | only in internal
      1 // Copyright 2005, Google Inc.
      2 // All rights reserved.
      3 //
      4 // Redistribution and use in source and binary forms, with or without
      5 // modification, are permitted provided that the following conditions are
      6 // met:
      7 //
      8 //     * Redistributions of source code must retain the above copyright
      9 // notice, this list of conditions and the following disclaimer.
     10 //     * Redistributions in binary form must reproduce the above
     11 // copyright notice, this list of conditions and the following disclaimer
     12 // in the documentation and/or other materials provided with the
     13 // distribution.
     14 //     * Neither the name of Google Inc. nor the names of its
     15 // contributors may be used to endorse or promote products derived from
     16 // this software without specific prior written permission.
     17 //
     18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     20 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     23 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     26 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     27 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     29 //
     30 // Authors: wan (at) google.com (Zhanyong Wan), eefacm (at) gmail.com (Sean Mcafee)
     31 //
     32 // The Google C++ Testing Framework (Google Test)
     33 //
     34 // This header file declares functions and macros used internally by
     35 // Google Test.  They are subject to change without notice.
     36 
     37 #ifndef GTEST_INCLUDE_GTEST_INTERNAL_GTEST_INTERNAL_H_
     38 #define GTEST_INCLUDE_GTEST_INTERNAL_GTEST_INTERNAL_H_
     39 
     40 #include <gtest/internal/gtest-port.h>
     41 
     42 #ifdef GTEST_OS_LINUX
     43 #include <stdlib.h>
     44 #include <sys/types.h>
     45 #include <sys/wait.h>
     46 #include <unistd.h>
     47 #endif  // GTEST_OS_LINUX
     48 
     49 #include <iomanip>  // NOLINT
     50 #include <limits>   // NOLINT
     51 
     52 #include <gtest/internal/gtest-string.h>
     53 #include <gtest/internal/gtest-filepath.h>
     54 
     55 // Due to C++ preprocessor weirdness, we need double indirection to
     56 // concatenate two tokens when one of them is __LINE__.  Writing
     57 //
     58 //   foo ## __LINE__
     59 //
     60 // will result in the token foo__LINE__, instead of foo followed by
     61 // the current line number.  For more details, see
     62 // http://www.parashift.com/c++-faq-lite/misc-technical-issues.html#faq-39.6
     63 #define GTEST_CONCAT_TOKEN(foo, bar) GTEST_CONCAT_TOKEN_IMPL(foo, bar)
     64 #define GTEST_CONCAT_TOKEN_IMPL(foo, bar) foo ## bar
     65 
     66 // Google Test defines the testing::Message class to allow construction of
     67 // test messages via the << operator.  The idea is that anything
     68 // streamable to std::ostream can be streamed to a testing::Message.
     69 // This allows a user to use his own types in Google Test assertions by
     70 // overloading the << operator.
     71 //
     72 // util/gtl/stl_logging-inl.h overloads << for STL containers.  These
     73 // overloads cannot be defined in the std namespace, as that will be
     74 // undefined behavior.  Therefore, they are defined in the global
     75 // namespace instead.
     76 //
     77 // C++'s symbol lookup rule (i.e. Koenig lookup) says that these
     78 // overloads are visible in either the std namespace or the global
     79 // namespace, but not other namespaces, including the testing
     80 // namespace which Google Test's Message class is in.
     81 //
     82 // To allow STL containers (and other types that has a << operator
     83 // defined in the global namespace) to be used in Google Test assertions,
     84 // testing::Message must access the custom << operator from the global
     85 // namespace.  Hence this helper function.
     86 //
     87 // Note: Jeffrey Yasskin suggested an alternative fix by "using
     88 // ::operator<<;" in the definition of Message's operator<<.  That fix
     89 // doesn't require a helper function, but unfortunately doesn't
     90 // compile with MSVC.
     91 template <typename T>
     92 inline void GTestStreamToHelper(std::ostream* os, const T& val) {
     93   *os << val;
     94 }
     95 
     96 namespace testing {
     97 
     98 // Forward declaration of classes.
     99 
    100 class Message;                         // Represents a failure message.
    101 class TestCase;                        // A collection of related tests.
    102 class TestPartResult;                  // Result of a test part.
    103 class TestInfo;                        // Information about a test.
    104 class UnitTest;                        // A collection of test cases.
    105 class UnitTestEventListenerInterface;  // Listens to Google Test events.
    106 class AssertionResult;                 // Result of an assertion.
    107 
    108 namespace internal {
    109 
    110 struct TraceInfo;                      // Information about a trace point.
    111 class ScopedTrace;                     // Implements scoped trace.
    112 class TestInfoImpl;                    // Opaque implementation of TestInfo
    113 class TestResult;                      // Result of a single Test.
    114 class UnitTestImpl;                    // Opaque implementation of UnitTest
    115 
    116 template <typename E> class List;      // A generic list.
    117 template <typename E> class ListNode;  // A node in a generic list.
    118 
    119 // A secret type that Google Test users don't know about.  It has no
    120 // definition on purpose.  Therefore it's impossible to create a
    121 // Secret object, which is what we want.
    122 class Secret;
    123 
    124 // Two overloaded helpers for checking at compile time whether an
    125 // expression is a null pointer literal (i.e. NULL or any 0-valued
    126 // compile-time integral constant).  Their return values have
    127 // different sizes, so we can use sizeof() to test which version is
    128 // picked by the compiler.  These helpers have no implementations, as
    129 // we only need their signatures.
    130 //
    131 // Given IsNullLiteralHelper(x), the compiler will pick the first
    132 // version if x can be implicitly converted to Secret*, and pick the
    133 // second version otherwise.  Since Secret is a secret and incomplete
    134 // type, the only expression a user can write that has type Secret* is
    135 // a null pointer literal.  Therefore, we know that x is a null
    136 // pointer literal if and only if the first version is picked by the
    137 // compiler.
    138 char IsNullLiteralHelper(Secret* p);
    139 char (&IsNullLiteralHelper(...))[2];  // NOLINT
    140 
    141 // A compile-time bool constant that is true if and only if x is a
    142 // null pointer literal (i.e. NULL or any 0-valued compile-time
    143 // integral constant).
    144 #ifdef __SYMBIAN32__  // Symbian
    145 // Passing non-POD classes through ellipsis (...) crashes the ARM compiler.
    146 // The Nokia Symbian compiler tries to instantiate a copy constructor for
    147 // objects passed through ellipsis (...), failing for uncopyable objects.
    148 // Hence we define this to false (and lose support for NULL detection).
    149 #define GTEST_IS_NULL_LITERAL(x) false
    150 #else  // ! __SYMBIAN32__
    151 #define GTEST_IS_NULL_LITERAL(x) \
    152     (sizeof(::testing::internal::IsNullLiteralHelper(x)) == 1)
    153 #endif  // __SYMBIAN32__
    154 
    155 // Appends the user-supplied message to the Google-Test-generated message.
    156 String AppendUserMessage(const String& gtest_msg,
    157                          const Message& user_msg);
    158 
    159 // A helper class for creating scoped traces in user programs.
    160 class ScopedTrace {
    161  public:
    162   // The c'tor pushes the given source file location and message onto
    163   // a trace stack maintained by Google Test.
    164   ScopedTrace(const char* file, int line, const Message& message);
    165 
    166   // The d'tor pops the info pushed by the c'tor.
    167   //
    168   // Note that the d'tor is not virtual in order to be efficient.
    169   // Don't inherit from ScopedTrace!
    170   ~ScopedTrace();
    171 
    172  private:
    173   GTEST_DISALLOW_COPY_AND_ASSIGN(ScopedTrace);
    174 } GTEST_ATTRIBUTE_UNUSED;  // A ScopedTrace object does its job in its
    175                            // c'tor and d'tor.  Therefore it doesn't
    176                            // need to be used otherwise.
    177 
    178 // Converts a streamable value to a String.  A NULL pointer is
    179 // converted to "(null)".  When the input value is a ::string,
    180 // ::std::string, ::wstring, or ::std::wstring object, each NUL
    181 // character in it is replaced with "\\0".
    182 // Declared here but defined in gtest.h, so that it has access
    183 // to the definition of the Message class, required by the ARM
    184 // compiler.
    185 template <typename T>
    186 String StreamableToString(const T& streamable);
    187 
    188 // Formats a value to be used in a failure message.
    189 
    190 #ifdef __SYMBIAN32__
    191 
    192 // These are needed as the Nokia Symbian Compiler cannot decide between
    193 // const T& and const T* in a function template. The Nokia compiler _can_
    194 // decide between class template specializations for T and T*, so a
    195 // tr1::type_traits-like is_pointer works, and we can overload on that.
    196 
    197 // This overload makes sure that all pointers (including
    198 // those to char or wchar_t) are printed as raw pointers.
    199 template <typename T>
    200 inline String FormatValueForFailureMessage(internal::true_type dummy,
    201                                            T* pointer) {
    202   return StreamableToString(static_cast<const void*>(pointer));
    203 }
    204 
    205 template <typename T>
    206 inline String FormatValueForFailureMessage(internal::false_type dummy,
    207                                            const T& value) {
    208   return StreamableToString(value);
    209 }
    210 
    211 template <typename T>
    212 inline String FormatForFailureMessage(const T& value) {
    213   return FormatValueForFailureMessage(
    214       typename internal::is_pointer<T>::type(), value);
    215 }
    216 
    217 #else
    218 
    219 template <typename T>
    220 inline String FormatForFailureMessage(const T& value) {
    221   return StreamableToString(value);
    222 }
    223 
    224 // This overload makes sure that all pointers (including
    225 // those to char or wchar_t) are printed as raw pointers.
    226 template <typename T>
    227 inline String FormatForFailureMessage(T* pointer) {
    228   return StreamableToString(static_cast<const void*>(pointer));
    229 }
    230 
    231 #endif  // __SYMBIAN32__
    232 
    233 // These overloaded versions handle narrow and wide characters.
    234 String FormatForFailureMessage(char ch);
    235 String FormatForFailureMessage(wchar_t wchar);
    236 
    237 // When this operand is a const char* or char*, and the other operand
    238 // is a ::std::string or ::string, we print this operand as a C string
    239 // rather than a pointer.  We do the same for wide strings.
    240 
    241 // This internal macro is used to avoid duplicated code.
    242 #define GTEST_FORMAT_IMPL(operand2_type, operand1_printer)\
    243 inline String FormatForComparisonFailureMessage(\
    244     operand2_type::value_type* str, const operand2_type& /*operand2*/) {\
    245   return operand1_printer(str);\
    246 }\
    247 inline String FormatForComparisonFailureMessage(\
    248     const operand2_type::value_type* str, const operand2_type& /*operand2*/) {\
    249   return operand1_printer(str);\
    250 }
    251 
    252 #if GTEST_HAS_STD_STRING
    253 GTEST_FORMAT_IMPL(::std::string, String::ShowCStringQuoted)
    254 #endif  // GTEST_HAS_STD_STRING
    255 #if GTEST_HAS_STD_WSTRING
    256 GTEST_FORMAT_IMPL(::std::wstring, String::ShowWideCStringQuoted)
    257 #endif  // GTEST_HAS_STD_WSTRING
    258 
    259 #if GTEST_HAS_GLOBAL_STRING
    260 GTEST_FORMAT_IMPL(::string, String::ShowCStringQuoted)
    261 #endif  // GTEST_HAS_GLOBAL_STRING
    262 #if GTEST_HAS_GLOBAL_WSTRING
    263 GTEST_FORMAT_IMPL(::wstring, String::ShowWideCStringQuoted)
    264 #endif  // GTEST_HAS_GLOBAL_WSTRING
    265 
    266 #undef GTEST_FORMAT_IMPL
    267 
    268 // Constructs and returns the message for an equality assertion
    269 // (e.g. ASSERT_EQ, EXPECT_STREQ, etc) failure.
    270 //
    271 // The first four parameters are the expressions used in the assertion
    272 // and their values, as strings.  For example, for ASSERT_EQ(foo, bar)
    273 // where foo is 5 and bar is 6, we have:
    274 //
    275 //   expected_expression: "foo"
    276 //   actual_expression:   "bar"
    277 //   expected_value:      "5"
    278 //   actual_value:        "6"
    279 //
    280 // The ignoring_case parameter is true iff the assertion is a
    281 // *_STRCASEEQ*.  When it's true, the string " (ignoring case)" will
    282 // be inserted into the message.
    283 AssertionResult EqFailure(const char* expected_expression,
    284                           const char* actual_expression,
    285                           const String& expected_value,
    286                           const String& actual_value,
    287                           bool ignoring_case);
    288 
    289 
    290 // This template class represents an IEEE floating-point number
    291 // (either single-precision or double-precision, depending on the
    292 // template parameters).
    293 //
    294 // The purpose of this class is to do more sophisticated number
    295 // comparison.  (Due to round-off error, etc, it's very unlikely that
    296 // two floating-points will be equal exactly.  Hence a naive
    297 // comparison by the == operation often doesn't work.)
    298 //
    299 // Format of IEEE floating-point:
    300 //
    301 //   The most-significant bit being the leftmost, an IEEE
    302 //   floating-point looks like
    303 //
    304 //     sign_bit exponent_bits fraction_bits
    305 //
    306 //   Here, sign_bit is a single bit that designates the sign of the
    307 //   number.
    308 //
    309 //   For float, there are 8 exponent bits and 23 fraction bits.
    310 //
    311 //   For double, there are 11 exponent bits and 52 fraction bits.
    312 //
    313 //   More details can be found at
    314 //   http://en.wikipedia.org/wiki/IEEE_floating-point_standard.
    315 //
    316 // Template parameter:
    317 //
    318 //   RawType: the raw floating-point type (either float or double)
    319 template <typename RawType>
    320 class FloatingPoint {
    321  public:
    322   // Defines the unsigned integer type that has the same size as the
    323   // floating point number.
    324   typedef typename TypeWithSize<sizeof(RawType)>::UInt Bits;
    325 
    326   // Constants.
    327 
    328   // # of bits in a number.
    329   static const size_t kBitCount = 8*sizeof(RawType);
    330 
    331   // # of fraction bits in a number.
    332   static const size_t kFractionBitCount =
    333     std::numeric_limits<RawType>::digits - 1;
    334 
    335   // # of exponent bits in a number.
    336   static const size_t kExponentBitCount = kBitCount - 1 - kFractionBitCount;
    337 
    338   // The mask for the sign bit.
    339   static const Bits kSignBitMask = static_cast<Bits>(1) << (kBitCount - 1);
    340 
    341   // The mask for the fraction bits.
    342   static const Bits kFractionBitMask =
    343     ~static_cast<Bits>(0) >> (kExponentBitCount + 1);
    344 
    345   // The mask for the exponent bits.
    346   static const Bits kExponentBitMask = ~(kSignBitMask | kFractionBitMask);
    347 
    348   // How many ULP's (Units in the Last Place) we want to tolerate when
    349   // comparing two numbers.  The larger the value, the more error we
    350   // allow.  A 0 value means that two numbers must be exactly the same
    351   // to be considered equal.
    352   //
    353   // The maximum error of a single floating-point operation is 0.5
    354   // units in the last place.  On Intel CPU's, all floating-point
    355   // calculations are done with 80-bit precision, while double has 64
    356   // bits.  Therefore, 4 should be enough for ordinary use.
    357   //
    358   // See the following article for more details on ULP:
    359   // http://www.cygnus-software.com/papers/comparingfloats/comparingfloats.htm.
    360   static const size_t kMaxUlps = 4;
    361 
    362   // Constructs a FloatingPoint from a raw floating-point number.
    363   //
    364   // On an Intel CPU, passing a non-normalized NAN (Not a Number)
    365   // around may change its bits, although the new value is guaranteed
    366   // to be also a NAN.  Therefore, don't expect this constructor to
    367   // preserve the bits in x when x is a NAN.
    368   explicit FloatingPoint(const RawType& x) : value_(x) {}
    369 
    370   // Static methods
    371 
    372   // Reinterprets a bit pattern as a floating-point number.
    373   //
    374   // This function is needed to test the AlmostEquals() method.
    375   static RawType ReinterpretBits(const Bits bits) {
    376     FloatingPoint fp(0);
    377     fp.bits_ = bits;
    378     return fp.value_;
    379   }
    380 
    381   // Returns the floating-point number that represent positive infinity.
    382   static RawType Infinity() {
    383     return ReinterpretBits(kExponentBitMask);
    384   }
    385 
    386   // Non-static methods
    387 
    388   // Returns the bits that represents this number.
    389   const Bits &bits() const { return bits_; }
    390 
    391   // Returns the exponent bits of this number.
    392   Bits exponent_bits() const { return kExponentBitMask & bits_; }
    393 
    394   // Returns the fraction bits of this number.
    395   Bits fraction_bits() const { return kFractionBitMask & bits_; }
    396 
    397   // Returns the sign bit of this number.
    398   Bits sign_bit() const { return kSignBitMask & bits_; }
    399 
    400   // Returns true iff this is NAN (not a number).
    401   bool is_nan() const {
    402     // It's a NAN if the exponent bits are all ones and the fraction
    403     // bits are not entirely zeros.
    404     return (exponent_bits() == kExponentBitMask) && (fraction_bits() != 0);
    405   }
    406 
    407   // Returns true iff this number is at most kMaxUlps ULP's away from
    408   // rhs.  In particular, this function:
    409   //
    410   //   - returns false if either number is (or both are) NAN.
    411   //   - treats really large numbers as almost equal to infinity.
    412   //   - thinks +0.0 and -0.0 are 0 DLP's apart.
    413   bool AlmostEquals(const FloatingPoint& rhs) const {
    414     // The IEEE standard says that any comparison operation involving
    415     // a NAN must return false.
    416     if (is_nan() || rhs.is_nan()) return false;
    417 
    418     return DistanceBetweenSignAndMagnitudeNumbers(bits_, rhs.bits_) <= kMaxUlps;
    419   }
    420 
    421  private:
    422   // Converts an integer from the sign-and-magnitude representation to
    423   // the biased representation.  More precisely, let N be 2 to the
    424   // power of (kBitCount - 1), an integer x is represented by the
    425   // unsigned number x + N.
    426   //
    427   // For instance,
    428   //
    429   //   -N + 1 (the most negative number representable using
    430   //          sign-and-magnitude) is represented by 1;
    431   //   0      is represented by N; and
    432   //   N - 1  (the biggest number representable using
    433   //          sign-and-magnitude) is represented by 2N - 1.
    434   //
    435   // Read http://en.wikipedia.org/wiki/Signed_number_representations
    436   // for more details on signed number representations.
    437   static Bits SignAndMagnitudeToBiased(const Bits &sam) {
    438     if (kSignBitMask & sam) {
    439       // sam represents a negative number.
    440       return ~sam + 1;
    441     } else {
    442       // sam represents a positive number.
    443       return kSignBitMask | sam;
    444     }
    445   }
    446 
    447   // Given two numbers in the sign-and-magnitude representation,
    448   // returns the distance between them as an unsigned number.
    449   static Bits DistanceBetweenSignAndMagnitudeNumbers(const Bits &sam1,
    450                                                      const Bits &sam2) {
    451     const Bits biased1 = SignAndMagnitudeToBiased(sam1);
    452     const Bits biased2 = SignAndMagnitudeToBiased(sam2);
    453     return (biased1 >= biased2) ? (biased1 - biased2) : (biased2 - biased1);
    454   }
    455 
    456   union {
    457     RawType value_;  // The raw floating-point number.
    458     Bits bits_;      // The bits that represent the number.
    459   };
    460 };
    461 
    462 // Typedefs the instances of the FloatingPoint template class that we
    463 // care to use.
    464 typedef FloatingPoint<float> Float;
    465 typedef FloatingPoint<double> Double;
    466 
    467 // In order to catch the mistake of putting tests that use different
    468 // test fixture classes in the same test case, we need to assign
    469 // unique IDs to fixture classes and compare them.  The TypeId type is
    470 // used to hold such IDs.  The user should treat TypeId as an opaque
    471 // type: the only operation allowed on TypeId values is to compare
    472 // them for equality using the == operator.
    473 typedef void* TypeId;
    474 
    475 // GetTypeId<T>() returns the ID of type T.  Different values will be
    476 // returned for different types.  Calling the function twice with the
    477 // same type argument is guaranteed to return the same ID.
    478 template <typename T>
    479 inline TypeId GetTypeId() {
    480   static bool dummy = false;
    481   // The compiler is required to create an instance of the static
    482   // variable dummy for each T used to instantiate the template.
    483   // Therefore, the address of dummy is guaranteed to be unique.
    484   return &dummy;
    485 }
    486 
    487 #ifdef GTEST_OS_WINDOWS
    488 
    489 // Predicate-formatters for implementing the HRESULT checking macros
    490 // {ASSERT|EXPECT}_HRESULT_{SUCCEEDED|FAILED}
    491 // We pass a long instead of HRESULT to avoid causing an
    492 // include dependency for the HRESULT type.
    493 AssertionResult IsHRESULTSuccess(const char* expr, long hr);  // NOLINT
    494 AssertionResult IsHRESULTFailure(const char* expr, long hr);  // NOLINT
    495 
    496 #endif  // GTEST_OS_WINDOWS
    497 
    498 }  // namespace internal
    499 }  // namespace testing
    500 
    501 #define GTEST_MESSAGE(message, result_type) \
    502   ::testing::internal::AssertHelper(result_type, __FILE__, __LINE__, message) \
    503     = ::testing::Message()
    504 
    505 #define GTEST_FATAL_FAILURE(message) \
    506   return GTEST_MESSAGE(message, ::testing::TPRT_FATAL_FAILURE)
    507 
    508 #define GTEST_NONFATAL_FAILURE(message) \
    509   GTEST_MESSAGE(message, ::testing::TPRT_NONFATAL_FAILURE)
    510 
    511 #define GTEST_SUCCESS(message) \
    512   GTEST_MESSAGE(message, ::testing::TPRT_SUCCESS)
    513 
    514 #define GTEST_TEST_BOOLEAN(boolexpr, booltext, actual, expected, fail) \
    515   GTEST_AMBIGUOUS_ELSE_BLOCKER \
    516   if (boolexpr) \
    517     ; \
    518   else \
    519     fail("Value of: " booltext "\n  Actual: " #actual "\nExpected: " #expected)
    520 
    521 // Helper macro for defining tests.
    522 #define GTEST_TEST(test_case_name, test_name, parent_class)\
    523 class test_case_name##_##test_name##_Test : public parent_class {\
    524  public:\
    525   test_case_name##_##test_name##_Test() {}\
    526   static ::testing::Test* NewTest() {\
    527     return new test_case_name##_##test_name##_Test;\
    528   }\
    529  private:\
    530   virtual void TestBody();\
    531   static ::testing::TestInfo* const test_info_;\
    532   GTEST_DISALLOW_COPY_AND_ASSIGN(test_case_name##_##test_name##_Test);\
    533 };\
    534 \
    535 ::testing::TestInfo* const test_case_name##_##test_name##_Test::test_info_ =\
    536   ::testing::TestInfo::MakeAndRegisterInstance(\
    537     #test_case_name, \
    538     #test_name, \
    539     ::testing::internal::GetTypeId< parent_class >(), \
    540     parent_class::SetUpTestCase, \
    541     parent_class::TearDownTestCase, \
    542     test_case_name##_##test_name##_Test::NewTest);\
    543 void test_case_name##_##test_name##_Test::TestBody()
    544 
    545 
    546 #endif  // GTEST_INCLUDE_GTEST_INTERNAL_GTEST_INTERNAL_H_
    547