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() : log_level_(0), log_handler_(NULL) { }
  48    :  
  49    :    // @name IO Stream Accessors.
  50    :    // Call InitStreams() to route the IO streams to/from specific files;
  51    :    // otherwise, they will be routed to/from the NUL device on first use.
  52    :    // @{
  53  E :    FILE* in() const { return GetOrInitFile(&in_, "r"); }
  54  E :    FILE* out() const { return GetOrInitFile(&out_, "w"); }
  55  E :    FILE* err() const { return GetOrInitFile(&err_, "w"); }
  56    :    // @}
  57    :  
  58    :    // Initialize the IO Streams to send output to specific files. Also intercepts
  59    :    // logging messages.
  60    :    void InitStreams(const base::FilePath& in_path,
  61    :                     const base::FilePath& out_path,
  62    :                     const base::FilePath& err_path);
  63    :  
  64    :    // Manually tear down the various streams.
  65    :    void TearDownStreams();
  66    :  
  67    :    // Creates a temporary directory, which is cleaned up after the test runs.
  68  E :    void CreateTemporaryDir(base::FilePath* temp_dir) {
  69  E :      ASSERT_TRUE(file_util::CreateNewTempDirectory(L"", temp_dir));
  70  E :      temp_dirs_.push_back(*temp_dir);
  71  E :    }
  72    :  
  73    :    // Sets up before each test invocation.
  74    :    virtual void SetUp() OVERRIDE;
  75    :  
  76    :    // Cleans up after each test invocation.
  77    :    virtual void TearDown() OVERRIDE;
  78    :  
  79    :    // Disables logging for the test in which this is called.
  80  E :    void DisableLogging() {
  81  E :      logging::SetMinLogLevel(logging::LOG_FATAL);
  82  E :    }
  83    :  
  84    :   protected:
  85    :    typedef testing::Test Super;
  86    :  
  87    :    // Used for logging interception, redirecting via err().
  88    :    static bool HandleLogMessage(int severity, const char* file, int line,
  89    :        size_t message_start, const std::string& str);
  90    :  
  91    :    // Tears down the given stream.
  92    :    static void TearDownStream(file_util::ScopedFILE* stream);
  93    :  
  94    :    // Helper to initialize a given stream to refer to the NUL device on first
  95    :    // use if it hasn't already been associated with a file.
  96    :    static FILE* GetOrInitFile(file_util::ScopedFILE* f, const char* mode);
  97    :  
  98    :    // List of temporary directories created during this test invocation.
  99    :    typedef std::vector<const base::FilePath> DirList;
 100    :    DirList temp_dirs_;
 101    :  
 102    :    // @name Replacements for the standard IO streams.
 103    :    //
 104    :    // By default they are routed to the NUL device (on first uninitialized use).
 105    :    //
 106    :    // @{
 107    :    mutable file_util::ScopedFILE in_;
 108    :    mutable file_util::ScopedFILE out_;
 109    :    mutable file_util::ScopedFILE err_;
 110    :    // @}
 111    :  
 112    :    // The logging level saved during SetUp. We restore this on TearDown.
 113    :    int log_level_;
 114    :  
 115    :    // The log message handler that was intercepted.
 116    :    logging::LogMessageHandlerFunction log_handler_;
 117    :  
 118    :    // The instance of this test that is redirecting logging. This only works for
 119    :    // a single instance at a time, but only one test is running at a time so
 120    :    // this is not really an issue.
 121    :    static ApplicationTestBase* self_;
 122    :  };
 123    :  
 124    :  }  // namespace testing
 125    :  
 126    :  #endif  // SYZYGY_COMMON_UNITTEST_UTIL_H_