1    :  // Copyright 2012 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  //
  15    :  // Declares a handful of common unittest helper functions.
  16    :  
  17    :  #ifndef SYZYGY_COMMON_UNITTEST_UTIL_H_
  18    :  #define SYZYGY_COMMON_UNITTEST_UTIL_H_
  19    :  
  20    :  #include "base/file_util.h"
  21    :  #include "base/logging.h"
  22    :  #include "base/files/file_path.h"
  23    :  #include "gtest/gtest.h"
  24    :  
  25    :  namespace testing {
  26    :  
  27    :  // Helper class to make sure that a test that plays with the log level doesn't
  28    :  // change it for other tests.
  29    :  class ScopedLogLevelSaver {
  30    :   public:
  31  E :    ScopedLogLevelSaver() : level_(logging::GetMinLogLevel()) {
  32  E :    }
  33    :  
  34  E :    ~ScopedLogLevelSaver() {
  35  E :      logging::SetMinLogLevel(level_);
  36  E :    }
  37    :  
  38    :    int level() const { return level_; }
  39    :  
  40    :   private:
  41    :    int level_;
  42    :  };
  43    :  
  44    :  // An intermediate class to add helper streams to a unit-test fixture.
  45    :  class ApplicationTestBase : public testing::Test {
  46    :   public:
  47  E :    ApplicationTestBase()
  48    :        : log_level_(0), log_handler_(NULL), log_to_console_(false) { }
  49    :  
  50    :    // @name IO Stream Accessors.
  51    :    // Call InitStreams() to route the IO streams to/from specific files;
  52    :    // otherwise, they will be routed to/from the NUL device on first use.
  53    :    // @{
  54  E :    FILE* in() const { return GetOrInitFile(&in_, "r"); }
  55  E :    FILE* out() const { return GetOrInitFile(&out_, "w"); }
  56  E :    FILE* err() const { return GetOrInitFile(&err_, "w"); }
  57    :    // @}
  58    :  
  59    :    // Initialize the IO Streams to send output to specific files. Also intercepts
  60    :    // logging messages.
  61    :    void InitStreams(const base::FilePath& in_path,
  62    :                     const base::FilePath& out_path,
  63    :                     const base::FilePath& err_path);
  64    :  
  65    :    // Manually tear down the various streams.
  66    :    void TearDownStreams();
  67    :  
  68    :    // Creates a temporary directory, which is cleaned up after the test runs.
  69  E :    void CreateTemporaryDir(base::FilePath* temp_dir) {
  70  E :      ASSERT_TRUE(base::CreateNewTempDirectory(L"", temp_dir));
  71  E :      temp_dirs_.push_back(*temp_dir);
  72  E :    }
  73    :  
  74    :    // Sets up before each test invocation.
  75    :    virtual void SetUp() OVERRIDE;
  76    :  
  77    :    // Cleans up after each test invocation.
  78    :    virtual void TearDown() OVERRIDE;
  79    :  
  80    :    // Disables logging for the test in which this is called.
  81  E :    void DisableLogging() {
  82  E :      logging::SetMinLogLevel(logging::LOG_FATAL);
  83  E :    }
  84    :  
  85    :    // Enables logging to screen for the test in which this is called.
  86    :    void EnableLoggingToConsole() {
  87    :      log_to_console_ = true;
  88    :    }
  89    :  
  90    :   protected:
  91    :    typedef testing::Test Super;
  92    :  
  93    :    // Used for logging interception, redirecting via err().
  94    :    static bool HandleLogMessage(int severity, const char* file, int line,
  95    :        size_t message_start, const std::string& str);
  96    :  
  97    :    // Tears down the given stream.
  98    :    static void TearDownStream(base::ScopedFILE* stream);
  99    :  
 100    :    // Helper to initialize a given stream to refer to the NUL device on first
 101    :    // use if it hasn't already been associated with a file.
 102    :    static FILE* GetOrInitFile(base::ScopedFILE* f, const char* mode);
 103    :  
 104    :    // List of temporary directories created during this test invocation.
 105    :    typedef std::vector<const base::FilePath> DirList;
 106    :    DirList temp_dirs_;
 107    :  
 108    :    // @name Replacements for the standard IO streams.
 109    :    //
 110    :    // By default they are routed to the NUL device (on first uninitialized use).
 111    :    //
 112    :    // @{
 113    :    mutable base::ScopedFILE in_;
 114    :    mutable base::ScopedFILE out_;
 115    :    mutable base::ScopedFILE err_;
 116    :    // @}
 117    :  
 118    :    // The logging level saved during SetUp. We restore this on TearDown.
 119    :    int log_level_;
 120    :  
 121    :    // The log message handler that was intercepted.
 122    :    logging::LogMessageHandlerFunction log_handler_;
 123    :  
 124    :    // If this is true then log messages handled by this fixture will be repeated
 125    :    // to the console rather than simply going to the wrapped stderr. Defaults to
 126    :    // false.
 127    :    bool log_to_console_;
 128    :  
 129    :    // The instance of this test that is redirecting logging. This only works for
 130    :    // a single instance at a time, but only one test is running at a time so
 131    :    // this is not really an issue.
 132    :    static ApplicationTestBase* self_;
 133    :  };
 134    :  
 135    :  }  // namespace testing
 136    :  
 137    :  #endif  // SYZYGY_COMMON_UNITTEST_UTIL_H_