/ externals / fmt / test / gtest-extra.h
gtest-extra.h
  1  // Formatting library for C++ - custom Google Test assertions
  2  //
  3  // Copyright (c) 2012 - present, Victor Zverovich
  4  // All rights reserved.
  5  //
  6  // For the license information refer to format.h.
  7  
  8  #ifndef FMT_GTEST_EXTRA_H_
  9  #define FMT_GTEST_EXTRA_H_
 10  
 11  #include <stdlib.h>  // _invalid_parameter_handler
 12  
 13  #include <string>
 14  
 15  #include "fmt/os.h"
 16  #include "gmock/gmock.h"
 17  
 18  #define FMT_TEST_THROW_(statement, expected_exception, expected_message, fail) \
 19    GTEST_AMBIGUOUS_ELSE_BLOCKER_                                                \
 20    if (::testing::AssertionResult gtest_ar = ::testing::AssertionSuccess()) {   \
 21      std::string gtest_expected_message = expected_message;                     \
 22      bool gtest_caught_expected = false;                                        \
 23      try {                                                                      \
 24        GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement);               \
 25      } catch (expected_exception const& e) {                                    \
 26        if (gtest_expected_message != e.what()) {                                \
 27          gtest_ar << #statement                                                 \
 28              " throws an exception with a different message.\n"                 \
 29                   << "Expected: " << gtest_expected_message << "\n"             \
 30                   << "  Actual: " << e.what();                                  \
 31          goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__);            \
 32        }                                                                        \
 33        gtest_caught_expected = true;                                            \
 34      } catch (...) {                                                            \
 35        gtest_ar << "Expected: " #statement                                      \
 36                    " throws an exception of type " #expected_exception          \
 37                    ".\n  Actual: it throws a different type.";                  \
 38        goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__);              \
 39      }                                                                          \
 40      if (!gtest_caught_expected) {                                              \
 41        gtest_ar << "Expected: " #statement                                      \
 42                    " throws an exception of type " #expected_exception          \
 43                    ".\n  Actual: it throws nothing.";                           \
 44        goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__);              \
 45      }                                                                          \
 46    } else                                                                       \
 47      GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__)                      \
 48          : fail(gtest_ar.failure_message())
 49  
 50  // Tests that the statement throws the expected exception and the exception's
 51  // what() method returns expected message.
 52  #define EXPECT_THROW_MSG(statement, expected_exception, expected_message) \
 53    FMT_TEST_THROW_(statement, expected_exception, expected_message,        \
 54                    GTEST_NONFATAL_FAILURE_)
 55  
 56  inline std::string system_error_message(int error_code,
 57                                          const std::string& message) {
 58    auto ec = std::error_code(error_code, std::generic_category());
 59    return std::system_error(ec, message).what();
 60  }
 61  
 62  #define EXPECT_SYSTEM_ERROR(statement, error_code, message) \
 63    EXPECT_THROW_MSG(statement, std::system_error,            \
 64                     system_error_message(error_code, message))
 65  
 66  #if FMT_USE_FCNTL
 67  
 68  // Captures file output by redirecting it to a pipe.
 69  // The output it can handle is limited by the pipe capacity.
 70  class output_redirect {
 71   private:
 72    FILE* file_;
 73    fmt::file original_;  // Original file passed to redirector.
 74    fmt::file read_end_;  // Read end of the pipe where the output is redirected.
 75  
 76    void flush();
 77    void restore();
 78  
 79   public:
 80    explicit output_redirect(FILE* file);
 81    ~output_redirect() noexcept;
 82  
 83    output_redirect(const output_redirect&) = delete;
 84    void operator=(const output_redirect&) = delete;
 85  
 86    // Restores the original file, reads output from the pipe into a string
 87    // and returns it.
 88    std::string restore_and_read();
 89  };
 90  
 91  #  define FMT_TEST_WRITE_(statement, expected_output, file, fail)              \
 92      GTEST_AMBIGUOUS_ELSE_BLOCKER_                                              \
 93      if (::testing::AssertionResult gtest_ar = ::testing::AssertionSuccess()) { \
 94        std::string gtest_expected_output = expected_output;                     \
 95        output_redirect gtest_redir(file);                                       \
 96        GTEST_SUPPRESS_UNREACHABLE_CODE_WARNING_BELOW_(statement);               \
 97        std::string gtest_output = gtest_redir.restore_and_read();               \
 98        if (gtest_output != gtest_expected_output) {                             \
 99          gtest_ar << #statement " produces different output.\n"                 \
100                   << "Expected: " << gtest_expected_output << "\n"              \
101                   << "  Actual: " << gtest_output;                              \
102          goto GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__);            \
103        }                                                                        \
104      } else                                                                     \
105        GTEST_CONCAT_TOKEN_(gtest_label_testthrow_, __LINE__)                    \
106            : fail(gtest_ar.failure_message())
107  
108  // Tests that the statement writes the expected output to file.
109  #  define EXPECT_WRITE(file, statement, expected_output) \
110      FMT_TEST_WRITE_(statement, expected_output, file, GTEST_NONFATAL_FAILURE_)
111  
112  #  ifdef _MSC_VER
113  
114  // Suppresses Windows assertions on invalid file descriptors, making
115  // POSIX functions return proper error codes instead of crashing on Windows.
116  class suppress_assert {
117   private:
118    _invalid_parameter_handler original_handler_;
119    int original_report_mode_;
120  
121    static void handle_invalid_parameter(const wchar_t*, const wchar_t*,
122                                         const wchar_t*, unsigned, uintptr_t) {}
123  
124   public:
125    suppress_assert()
126        : original_handler_(
127              _set_invalid_parameter_handler(handle_invalid_parameter)),
128          original_report_mode_(_CrtSetReportMode(_CRT_ASSERT, 0)) {}
129    ~suppress_assert() {
130      _set_invalid_parameter_handler(original_handler_);
131      _CrtSetReportMode(_CRT_ASSERT, original_report_mode_);
132      (void)original_report_mode_;
133    }
134  };
135  
136  #    define SUPPRESS_ASSERT(statement) \
137        {                                \
138          suppress_assert sa;            \
139          statement;                     \
140        }
141  #  else
142  #    define SUPPRESS_ASSERT(statement) statement
143  #  endif  // _MSC_VER
144  
145  #  define EXPECT_SYSTEM_ERROR_NOASSERT(statement, error_code, message) \
146      EXPECT_SYSTEM_ERROR(SUPPRESS_ASSERT(statement), error_code, message)
147  
148  // Attempts to read count characters from a file.
149  std::string read(fmt::file& f, size_t count);
150  
151  #  define EXPECT_READ(file, expected_content) \
152      EXPECT_EQ(expected_content,               \
153                read(file, fmt::string_view(expected_content).size()))
154  
155  #else
156  #  define EXPECT_WRITE(file, statement, expected_output) \
157      do {                                                 \
158        (void)(file);                                      \
159        (void)(statement);                                 \
160        (void)(expected_output);                           \
161        SUCCEED();                                         \
162      } while (false)
163  #endif  // FMT_USE_FCNTL
164  
165  #endif  // FMT_GTEST_EXTRA_H_