blob: da25e7606d77fe79df204c6a3796cc9004672511 [file] [log] [blame]
// Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef SHILL_MOCK_LOG_H_
#define SHILL_MOCK_LOG_H_
// ScopedMockLog provides a way for unittests to validate log messages. You can
// set expectations that certain log messages will be emited by your functions.
// To use ScopedMockLog, simply create a ScopedMockLog in your test and set
// expectations on its Log() method. When the ScopedMockLog object goes out of
// scope, the log messages sent to it will be verified against expectations.
//
// Note: Use only one ScopedMockLog in a test because more than one won't work!
//
// Sample usage:
//
// You can verify that a function "DoSomething" emits a specific log text:
//
// TEST_F(YourTest, DoesSomething) {
// ScopedMockLog log;
// EXPECT_CALL(log, Log(_, _, "Some log message text"));
// DoSomething(); // Causes "Some log message text" to be logged.
// }
//
// If the function DoSomething() executes something like:
//
// LOG(INFO) << "Some log message text";
//
// then this will match the expectation.
//
// The first two parameters to ScopedMockLog::Log are the log severity and
// filename. You can use them like this:
//
// TEST_F(MockLogTest, MockLogSeverityAndFileAndMessage) {
// ScopedMockLog log;
// EXPECT_CALL(log, Log(logging::LOG_INFO, "your_file.cc", "your message"));
// DoSomething();
// }
//
// You can also use gMock matchers for matching arguments to Log():
//
// TEST_F(MockLogTest, MatchWithGmockMatchers) {
// ScopedMockLog log;
// EXPECT_CALL(log, Log(::testing::Lt(::logging::LOG_ERROR),
// ::testing::EndsWith(".cc"),
// ::testing::StartsWith("Some")));
// DoSomething();
// }
//
// For some examples, see mock_log_unittest.cc.
#include <string>
#include <base/logging.h>
#include <gmock/gmock.h>
namespace shill {
class ScopedMockLog {
public:
ScopedMockLog();
~ScopedMockLog();
// Users set expecations on this method. |severity| is defined in
// base/logging.h, like logging:::LOG_INFO. |file| is the filename which
// issues the log message, like "foo.cc". |user_messages| is the message you
// expect to see. Arguments can be ignored by specifying ::testing::_. You
// can also specify gMock matchers for arguments.
MOCK_METHOD3(Log, void(int severity, const char *file,
const std::string &user_message));
private:
// This function gets invoked by the logging subsystem for each message that
// is logged. It calls ScopedMockLog::Log() declared above. It must be a
// static method because the logging subsystem does not allow for an object to
// be passed. See the typedef LogMessageHandlerFunction in base/logging.h for
// this function signature.
static bool HandleLogMessages(int severity,
const char *file,
int line,
size_t message_start,
const std::string &full_message);
// A pointer to the current ScopedMockLog object.
static ScopedMockLog *instance_;
// A pointer to any pre-existing message hander function in the logging
// system. It is invoked after calling ScopedMockLog::Log().
::logging::LogMessageHandlerFunction previous_handler_;
};
} // namespace shill
#endif // SHILL_MOCK_LOG_H_