googletest/include/gtest/gtest-spi.h

// Copyright 2007, Google Inc.
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//
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// Author: wan@google.com (Zhanyong Wan)
//
// Utilities for testing Google Test itself and code that uses Google Test
// (e.g. frameworks built on top of Google Test).

#ifndef GTEST_INCLUDE_GTEST_GTEST_SPI_H_
#define GTEST_INCLUDE_GTEST_GTEST_SPI_H_

#include "gtest/gtest.h"

namespace testing {

// This helper class can be used to mock out Google Test failure reporting
// so that we can test Google Test or code that builds on Google Test.
//
// An object of this class appends a TestPartResult object to the
// TestPartResultArray object given in the constructor whenever a Google Test
// failure is reported. It can either intercept only failures that are
// generated in the same thread that created this object or it can intercept
// all generated failures. The scope of this mock object can be controlled with
// the second argument to the two arguments constructor.
class GTEST_API_ ScopedFakeTestPartResultReporter
    : public TestPartResultReporterInterface {
 public:
  // The two possible mocking modes of this object.
  enum InterceptMode {
    INTERCEPT_ONLY_CURRENT_THREAD,  // Intercepts only thread local failures.
    INTERCEPT_ALL_THREADS           // Intercepts all failures.
  };

  // The c'tor sets this object as the test part result reporter used
  // by Google Test.  The 'result' parameter specifies where to report the
  // results. This reporter will only catch failures generated in the current
  // thread. DEPRECATED
  explicit ScopedFakeTestPartResultReporter(TestPartResultArray* result);

  // Same as above, but you can choose the interception scope of this object.
  ScopedFakeTestPartResultReporter(InterceptMode intercept_mode,
                                   TestPartResultArray* result);

  // The d'tor restores the previous test part result reporter.
  virtual ~ScopedFakeTestPartResultReporter();

  // Appends the TestPartResult object to the TestPartResultArray
  // received in the constructor.
  //
  // This method is from the TestPartResultReporterInterface
  // interface.
  virtual void ReportTestPartResult(const TestPartResult& result);
 private:
  void Init();

  const InterceptMode intercept_mode_;
  TestPartResultReporterInterface* old_reporter_;
  TestPartResultArray* const result_;

  GTEST_DISALLOW_COPY_AND_ASSIGN_(ScopedFakeTestPartResultReporter);
};

namespace internal {

// A helper class for implementing EXPECT_FATAL_FAILURE() and
// EXPECT_NONFATAL_FAILURE().  Its destructor verifies that the given
// TestPartResultArray contains exactly one failure that has the given
// type and contains the given substring.  If that's not the case, a
// non-fatal failure will be generated.
class GTEST_API_ SingleFailureChecker {
 public:
  // The constructor remembers the arguments.
  SingleFailureChecker(const TestPartResultArray* results,
                       TestPartResult::Type type,
                       const string& substr);
  ~SingleFailureChecker();
 private:
  const TestPartResultArray* const results_;
  const TestPartResult::Type type_;
  const string substr_;

  GTEST_DISALLOW_COPY_AND_ASSIGN_(SingleFailureChecker);
};

}  // namespace internal

}  // namespace testing

// A set of macros for testing Google Test assertions or code that's expected
// to generate Google Test fatal failures.  It verifies that the given
// statement will cause exactly one fatal Google Test failure with 'substr'
// being part of the failure message.
//
// There are two different versions of this macro. EXPECT_FATAL_FAILURE only
// affects and considers failures generated in the current thread and
// EXPECT_FATAL_FAILURE_ON_ALL_THREADS does the same but for all threads.
//
// The verification of the assertion is done correctly even when the statement
// throws an exception or aborts the current function.
//
// Known restrictions:
//   - 'statement' cannot reference local non-static variables or
//     non-static members of the current object.
//   - 'statement' cannot return a value.
//   - You cannot stream a failure message to this macro.
//
// Note that even though the implementations of the following two
// macros are much alike, we cannot refactor them to use a common
// helper macro, due to some peculiarity in how the preprocessor
// works.  The AcceptsMacroThatExpandsToUnprotectedComma test in
// gtest_unittest.cc will fail to compile if we do that.
#define EXPECT_FATAL_FAILURE(statement, substr) \
  do { \
    class GTestExpectFatalFailureHelper {\
     public:\
      static void Execute() { statement; }\
    };\
    ::testing::TestPartResultArray gtest_failures;\
    ::testing::internal::SingleFailureChecker gtest_checker(\
        &gtest_failures, ::testing::TestPartResult::kFatalFailure, (substr));\
    {\
      ::testing::ScopedFakeTestPartResultReporter gtest_reporter(\
          ::testing::ScopedFakeTestPartResultReporter:: \
          INTERCEPT_ONLY_CURRENT_THREAD, &gtest_failures);\
      GTestExpectFatalFailureHelper::Execute();\
    }\
  } while (::testing::internal::AlwaysFalse())

#define EXPECT_FATAL_FAILURE_ON_ALL_THREADS(statement, substr) \
  do { \
    class GTestExpectFatalFailureHelper {\
     public:\
      static void Execute() { statement; }\
    };\
    ::testing::TestPartResultArray gtest_failures;\
    ::testing::internal::SingleFailureChecker gtest_checker(\
        &gtest_failures, ::testing::TestPartResult::kFatalFailure, (substr));\
    {\
      ::testing::ScopedFakeTestPartResultReporter gtest_reporter(\
          ::testing::ScopedFakeTestPartResultReporter:: \
          INTERCEPT_ALL_THREADS, &gtest_failures);\
      GTestExpectFatalFailureHelper::Execute();\
    }\
  } while (::testing::internal::AlwaysFalse())

// A macro for testing Google Test assertions or code that's expected to
// generate Google Test non-fatal failures.  It asserts that the given
// statement will cause exactly one non-fatal Google Test failure with 'substr'
// being part of the failure message.
//
// There are two different versions of this macro. EXPECT_NONFATAL_FAILURE only
// affects and considers failures generated in the current thread and
// EXPECT_NONFATAL_FAILURE_ON_ALL_THREADS does the same but for all threads.
//
// 'statement' is allowed to reference local variables and members of
// the current object.
//
// The verification of the assertion is done correctly even when the statement
// throws an exception or aborts the current function.
//
// Known restrictions:
//   - You cannot stream a failure message to this macro.
//
// Note that even though the implementations of the following two
// macros are much alike, we cannot refactor them to use a common
// helper macro, due to some peculiarity in how the preprocessor
// works.  If we do that, the code won't compile when the user gives
// EXPECT_NONFATAL_FAILURE() a statement that contains a macro that
// expands to code containing an unprotected comma.  The
// AcceptsMacroThatExpandsToUnprotectedComma test in gtest_unittest.cc
// catches that.
//
// For the same reason, we have to write
//   if (::testing::internal::AlwaysTrue()) { statement; }
// instead of
//   GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement)
// to avoid an MSVC warning on unreachable code.
#define EXPECT_NONFATAL_FAILURE(statement, substr) \
  do {\
    ::testing::TestPartResultArray gtest_failures;\
    ::testing::internal::SingleFailureChecker gtest_checker(\
        &gtest_failures, ::testing::TestPartResult::kNonFatalFailure, \
        (substr));\
    {\
      ::testing::ScopedFakeTestPartResultReporter gtest_reporter(\
          ::testing::ScopedFakeTestPartResultReporter:: \
          INTERCEPT_ONLY_CURRENT_THREAD, &gtest_failures);\
      if (::testing::internal::AlwaysTrue()) { statement; }\
    }\
  } while (::testing::internal::AlwaysFalse())

#define EXPECT_NONFATAL_FAILURE_ON_ALL_THREADS(statement, substr) \
  do {\
    ::testing::TestPartResultArray gtest_failures;\
    ::testing::internal::SingleFailureChecker gtest_checker(\
        &gtest_failures, ::testing::TestPartResult::kNonFatalFailure, \
        (substr));\
    {\
      ::testing::ScopedFakeTestPartResultReporter gtest_reporter(\
          ::testing::ScopedFakeTestPartResultReporter::INTERCEPT_ALL_THREADS,\
          &gtest_failures);\
      if (::testing::internal::AlwaysTrue()) { statement; }\
    }\
  } while (::testing::internal::AlwaysFalse())

#endif  // GTEST_INCLUDE_GTEST_GTEST_SPI_H_