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Please review the following information to ensure ** the GNU Free Documentation License version 1.3 requirements ** will be met: http://www.gnu.org/copyleft/fdl.html. ** $QT_END_LICENSE$ ** ****************************************************************************/ /*! \page qtest-overview.html \title Qt Test Overview \brief Overview of the Qt unit testing framework. \ingroup frameworks-technologies \ingroup qt-basic-concepts \keyword qtestlib Qt Test is a framework for unit testing Qt based applications and libraries. Qt Test provides all the functionality commonly found in unit testing frameworks as well as extensions for testing graphical user interfaces. Qt Test is designed to ease the writing of unit tests for Qt based applications and libraries: \table \header \li Feature \li Details \row \li \b Lightweight \li Qt Test consists of about 6000 lines of code and 60 exported symbols. \row \li \b Self-contained \li Qt Test requires only a few symbols from the Qt Core module for non-gui testing. \row \li \b {Rapid testing} \li Qt Test needs no special test-runners; no special registration for tests. \row \li \b {Data-driven testing} \li A test can be executed multiple times with different test data. \row \li \b {Basic GUI testing} \li Qt Test offers functionality for mouse and keyboard simulation. \row \li \b {Benchmarking} \li Qt Test supports benchmarking and provides several measurement back-ends. \row \li \b {IDE friendly} \li Qt Test outputs messages that can be interpreted by Visual Studio and KDevelop. \row \li \b Thread-safety \li The error reporting is thread safe and atomic. \row \li \b Type-safety \li Extensive use of templates prevent errors introduced by implicit type casting. \row \li \b {Easily extendable} \li Custom types can easily be added to the test data and test output. \endtable \section1 Creating a Test To create a test, subclass QObject and add one or more private slots to it. Each private slot is a test function in your test. QTest::qExec() can be used to execute all test functions in the test object. In addition, there are four private slots that are \e not treated as test functions. They will be executed by the testing framework and can be used to initialize and clean up either the entire test or the current test function. \list \li \c{initTestCase()} will be called before the first test function is executed. \li \c{cleanupTestCase()} will be called after the last test function was executed. \li \c{init()} will be called before each test function is executed. \li \c{cleanup()} will be called after every test function. \endlist If \c{initTestCase()} fails, no test function will be executed. If \c{init()} fails, the following test function will not be executed, the test will proceed to the next test function. Example: \snippet code/doc_src_qtestlib.cpp 0 For more examples, refer to the \l{Qt Test Tutorial}. \section1 Building a Test If you are using \c qmake as your build tool, just add the following to your project file: \snippet code/doc_src_qtestlib.pro 1 If you would like to run the test via \c{make check}, add the additional line: \snippet code/doc_src_qtestlib.pro 2 See \l{qmake Common Projects#building-a-testcase}{the qmake manual} for more information about \c{make check}. If you are using other build tools, make sure that you add the location of the Qt Test header files to your include path (usually \c{include/QtTest} under your Qt installation directory). If you are using a release build of Qt, link your test to the \c QtTest library. For debug builds, use \c{QtTest_debug}. See \l {Chapter 1: Writing a Unit Test}{Writing a Unit Test} for a step by step explanation. \section1 Qt Test Command Line Arguments \section2 Syntax The syntax to execute an autotest takes the following simple form: \snippet code/doc_src_qtestlib.qdoc 2 Substitute \c testname with the name of your executable. \c testfunctions can contain names of test functions to be executed. If no \c testfunctions are passed, all tests are run. If you append the name of an entry in \c testdata, the test function will be run only with that test data. For example: \snippet code/doc_src_qtestlib.qdoc 3 Runs the test function called \c toUpper with all available test data. \snippet code/doc_src_qtestlib.qdoc 4 Runs the \c toUpper test function with all available test data, and the \c toInt test function with the test data called \c zero (if the specified test data doesn't exist, the associated test will fail). \snippet code/doc_src_qtestlib.qdoc 5 Runs the \c testMyWidget function test, outputs every signal emission and waits 500 milliseconds after each simulated mouse/keyboard event. \section2 Options \section3 Logging Options The following command line options determine how test results are reported: \list \li \c -o \e{filename,format} \br Writes output to the specified file, in the specified format (one of \c txt, \c xml, \c lightxml or \c xunitxml). The special filename \c - may be used to log to standard output. \li \c -o \e filename \br Writes output to the specified file. \li \c -txt \br Outputs results in plain text. \li \c -xml \br Outputs results as an XML document. \li \c -lightxml \br Outputs results as a stream of XML tags. \li \c -xunitxml \br Outputs results as an Xunit XML document. \endlist The first version of the \c -o option may be repeated in order to log test results in multiple formats, but no more than one instance of this option can log test results to standard output. If the first version of the \c -o option is used, neither the second version of the \c -o option nor the \c -txt, \c -xml, \c -lightxml or \c -xunitxml options should be used. If neither version of the \c -o option is used, test results will be logged to standard output. If no format option is used, test results will be logged in plain text. \section3 Test Log Detail Options The following command line options control how much detail is reported in test logs: \list \li \c -silent \br Silent output; only shows fatal errors, test failures and minimal status messages. \li \c -v1 \br Verbose output; shows when each test function is entered. (This option only affects plain text output.) \li \c -v2 \br Extended verbose output; shows each \l QCOMPARE() and \l QVERIFY(). (This option affects all output formats and implies \c -v1 for plain text output.) \li \c -vs \br Shows all signals that get emitted and the slot invocations resulting from those signals. (This option affects all output formats.) \endlist \section3 Testing Options The following command-line options influence how tests are run: \list \li \c -functions \br Outputs all test functions available in the test, then quits. \li \c -datatags \br Outputs all data tags available in the test. A global data tag is preceded by ' __global__ '. \li \c -eventdelay \e ms \br If no delay is specified for keyboard or mouse simulation (\l QTest::keyClick(), \l QTest::mouseClick() etc.), the value from this parameter (in milliseconds) is substituted. \li \c -keydelay \e ms \br Like -eventdelay, but only influences keyboard simulation and not mouse simulation. \li \c -mousedelay \e ms \br Like -eventdelay, but only influences mouse simulation and not keyboard simulation. \li \c -maxwarnings \e number \br Sets the maximum number of warnings to output. 0 for unlimited, defaults to 2000. \li \c -nocrashhandler \br Disables the crash handler on Unix platforms. \li \c -platform \e name \br This command line argument applies to all Qt applications, but might be especially useful in the context of auto-testing. By using the "offscreen" platform plugin (-platform offscreen) it's possible to have tests that use QWidget or QWindow run without showing anything on the screen. Currently the offscreen platform plugin is only fully supported on X11. \endlist \section3 Benchmarking Options The following command line options control benchmark testing: \list \li \c -callgrind \br Uses Callgrind to time benchmarks (Linux only). \li \c -tickcounter \br Uses CPU tick counters to time benchmarks. \li \c -eventcounter \br Counts events received during benchmarks. \li \c -minimumvalue \e n \br Sets the minimum acceptable measurement value. \li \c -minimumtotal \e n \br Sets the minimum acceptable total for repeated executions of a test function. \li \c -iterations \e n \br Sets the number of accumulation iterations. \li \c -median \e n \br Sets the number of median iterations. \li \c -vb \br Outputs verbose benchmarking information. \endlist \section3 Miscellaneous Options \list \li \c -help \br Outputs the possible command line arguments and gives some useful help. \endlist \section1 Creating a Benchmark To create a benchmark, follow the instructions for creating a test and then add a QBENCHMARK macro to the test function that you want to benchmark. \snippet code/doc_src_qtestlib.cpp 12 The code inside the QBENCHMARK macro will be measured, and possibly also repeated several times in order to get an accurate measurement. This depends on the selected measurement back-end. Several back-ends are available. They can be selected on the command line: \target testlib-benchmarking-measurement \table \header \li Name \li Command-line Argument \li Availability \row \li Walltime \li (default) \li All platforms \row \li CPU tick counter \li -tickcounter \li Windows, Mac OS X, Linux, many UNIX-like systems. \row \li Valgrind Callgrind \li -callgrind \li Linux (if installed) \row \li Event Counter \li -eventcounter \li All platforms \endtable In short, walltime is always available but requires many repetitions to get a useful result. Tick counters are usually available and can provide results with fewer repetitions, but can be susceptible to CPU frequency scaling issues. Valgrind provides exact results, but does not take I/O waits into account, and is only available on a limited number of platforms. Event counting is available on all platforms and it provides the number of events that were received by the event loop before they are sent to their corresponding targets (this might include non-Qt events). \note Depending on the device configuration, tick counters on the Windows CE platform may not be as fine-grained, compared to other platforms. Devices that do not support high-resolution timers default to one-millisecond granularity. See \l {Chapter 5: Writing a Benchmark}{Writing a Benchmark} in the Qt Test Tutorial for more benchmarking examples. \section1 Using Qt Test Remotely on Windows CE The \c cetest convenience application enables you to launch an application remotely on a Windows CE device or emulator. It needs to be executed after the unit test has been successfully compiled. Prior to launching, the following files are copied to the device: \list \li all Qt libraries the project links to \li \l {QtRemote}{QtRemote.dll} \li the c runtime library specified during installation \li all files specified in the \c .pro file following the \l DEPLOYMENT rules. \endlist \section2 Syntax The syntax to execute an autotest takes the following simple form: \snippet code/doc_src_qtestlib.qdoc 6 \section2 Options \c cetest provides the same options as those for unit-testing on non cross-compiled platforms. See \l {Qt Test Command Line Arguments} {Command Line Arguments} for more information. The following commands are also included: \list \li \c -debug \br Compiles the test version in debug mode. \li \c -release \br Compiles the test version in release mode. \li \c -libpath \e path \br Copies Qt libraries to the specified path. \li \c -qt-delete \br Deletes Qt libraries after execution. \li \c -project-delete \br Deletes project files after execution. \li \c -delete \br Deletes project and Qt libraries after execution. \li \c -conf \br Specifies a qt.conf file to be deployed to remote directory. \endlist \note \c{debug} is the default build option. \section2 QtRemote \c QtRemote is a small library which is built after Qt Test. It allows the host system to create a process on a remote device and waits until its execution has been finished. \section2 Requirements \c cetest uses Microsoft ActiveSync to establish a remote connection between the host computer and the device. Thus header files and libraries are needed to compile cetest and QtRemote successfully. Prior to \l{Installing Qt for Windows CE}{installation} of Qt, you need to set your \c INCLUDE and \c LIB environment variables properly. A default installation of Windows Mobile 5 for Pocket PC can be obtained by: \snippet code/doc_src_qtestlib.qdoc 7 Note that Qt will remember the path, so you do not need to set it again after switching the environments for cross-compilation. \section1 3rd Party Code The CPU tick counters used for benchmarking are licensed under the following license: (from src/testlib/3rdparty/cycle.h) \legalese Copyright (c) 2003, 2006 Matteo Frigo\br Copyright (c) 2003, 2006 Massachusetts Institute of Technology Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. \endlegalese */ /*! \page qtest-tutorial.html \brief A short introduction to testing with Qt Test. \contentspage Qt Test Overview \nextpage {Chapter 1: Writing a Unit Test}{Chapter 1} \ingroup best-practices \title Qt Test Tutorial This tutorial gives a short introduction to how to use some of the features of the Qt Test framework. It is divided into five chapters: \list 1 \li \l {Chapter 1: Writing a Unit Test}{Writing a Unit Test} \li \l {Chapter 2: Data Driven Testing}{Data Driven Testing} \li \l {Chapter 3: Simulating GUI Events}{Simulating GUI Events} \li \l {Chapter 4: Replaying GUI Events}{Replaying GUI Events} \li \l {Chapter 5: Writing a Benchmark}{Writing a Benchmark} \endlist */ /*! \example tutorial1 \contentspage {Qt Test Tutorial}{Contents} \nextpage {Chapter 2: Data Driven Testing}{Chapter 2} \title Chapter 1: Writing a Unit Test In this first chapter we will see how to write a simple unit test for a class, and how to execute it. \section1 Writing a Test Let's assume you want to test the behavior of our QString class. First, you need a class that contains your test functions. This class has to inherit from QObject: \snippet tutorial1/testqstring.cpp 0 \note You need to include the QTest header and declare the test functions as private slots so the test framework finds and executes it. Then you need to implement the test function itself. The implementation could look like this: \snippet code/doc_src_qtestlib.cpp 8 The \l QVERIFY() macro evaluates the expression passed as its argument. If the expression evaluates to true, the execution of the test function continues. Otherwise, a message describing the failure is appended to the test log, and the test function stops executing. But if you want a more verbose output to the test log, you should use the \l QCOMPARE() macro instead: \snippet tutorial1/testqstring.cpp 1 If the strings are not equal, the contents of both strings are appended to the test log, making it immediately visible why the comparison failed. Finally, to make our test case a stand-alone executable, the following two lines are needed: \snippet tutorial1/testqstring.cpp 2 The \l QTEST_MAIN() macro expands to a simple \c main() method that runs all the test functions. Note that if both the declaration and the implementation of our test class are in a \c .cpp file, we also need to include the generated moc file to make Qt's introspection work. \section1 Executing a Test Now that we finished writing our test, we want to execute it. Assuming that our test was saved as \c testqstring.cpp in an empty directory, we build the test using qmake to create a project and generate a makefile. \snippet code/doc_src_qtestlib.qdoc 9 \note If you're using windows, replace \c make with \c nmake or whatever build tool you use. Running the resulting executable should give you the following output: \snippet code/doc_src_qtestlib.qdoc 10 Congratulations! You just wrote and executed your first unit test using the Qt Test framework. */ /*! \example tutorial2 \previouspage {Chapter 1: Writing a Unit Test}{Chapter 1} \contentspage {Qt Test Tutorial}{Contents} \nextpage {Chapter 3: Simulating Gui Events}{Chapter 3} \title Chapter 2: Data Driven Testing In this chapter we will demonstrate how to execute a test multiple times with different test data. So far, we have hard coded the data we wanted to test into our test function. If we add more test data, the function might look like this: \snippet code/doc_src_qtestlib.cpp 11 To prevent that the function ends up being cluttered by repetitive code, Qt Test supports adding test data to a test function. All we need is to add another private slot to our test class: \snippet tutorial2/testqstring.cpp 0 \section1 Writing the Data Function A test function's associated data function carries the same name, appended by \c{_data}. Our data function looks like this: \snippet tutorial2/testqstring.cpp 1 First, we define the two elements of our test table using the \l QTest::addColumn() function: a test string, and the expected result of applying the QString::toUpper() function to that string. Then we add some data to the table using the \l QTest::newRow() function. Each set of data will become a separate row in the test table. \l QTest::newRow() takes one argument: a name that will be associated with the data set. If the test fails, the name will be used in the test log, referencing the failed data. Then we stream the data set into the new table row. First an arbitrary string, and then the expected result of applying the QString::toUpper() function to that string. You can think of the test data as a two-dimensional table. In our case, it has two columns called \c string and \c result and three rows. In addition a name as well as an index is associated with each row: \table \header \li index \li name \li string \li result \row \li 0 \li all lower \li "hello" \li HELLO \row \li 1 \li mixed \li "Hello" \li HELLO \row \li 2 \li all upper \li "HELLO" \li HELLO \endtable \section1 Rewriting the Test Function Our test function can now be rewritten: \snippet tutorial2/testqstring.cpp 2 The TestQString::toUpper() function will be executed three times, once for each entry in the test table that we created in the associated TestQString::toUpper_data() function. First, we fetch the two elements of the data set using the \l QFETCH() macro. \l QFETCH() takes two arguments: The data type of the element and the element name. Then we perform the test using the \l QCOMPARE() macro. This approach makes it very easy to add new data to the test without modifying the test itself. And again, to make our test case a stand-alone executable, the following two lines are needed: \snippet tutorial2/testqstring.cpp 3 As before, the QTEST_MAIN() macro expands to a simple main() method that runs all the test functions, and since both the declaration and the implementation of our test class are in a .cpp file, we also need to include the generated moc file to make Qt's introspection work. */ /*! \example tutorial3 \previouspage {Chapter 2: Data Driven Testing}{Chapter 2} \contentspage {Qt Test Tutorial}{Contents} \nextpage {Chapter 4: Replaying GUI Events}{Chapter 4} \title Chapter 3: Simulating GUI Events Qt Test features some mechanisms to test graphical user interfaces. Instead of simulating native window system events, Qt Test sends internal Qt events. That means there are no side-effects on the machine the tests are running on. In this chapter we will see how to write a simple GUI test. \section1 Writing a GUI test This time, let's assume you want to test the behavior of our QLineEdit class. As before, you will need a class that contains your test function: \snippet tutorial3/testgui.cpp 0 The only difference is that you need to include the Qt GUI class definitions in addition to the QTest namespace. \snippet tutorial3/testgui.cpp 1 In the implementation of the test function we first create a QLineEdit. Then we simulate writing "hello world" in the line edit using the \l QTest::keyClicks() function. \note The widget must also be shown in order to correctly test keyboard shortcuts. QTest::keyClicks() simulates clicking a sequence of keys on a widget. Optionally, a keyboard modifier can be specified as well as a delay (in milliseconds) of the test after each key click. In a similar way, you can use the QTest::keyClick(), QTest::keyPress(), QTest::keyRelease(), QTest::mouseClick(), QTest::mouseDClick(), QTest::mouseMove(), QTest::mousePress() and QTest::mouseRelease() functions to simulate the associated GUI events. Finally, we use the \l QCOMPARE() macro to check if the line edit's text is as expected. As before, to make our test case a stand-alone executable, the following two lines are needed: \snippet tutorial3/testgui.cpp 2 The QTEST_MAIN() macro expands to a simple main() method that runs all the test functions, and since both the declaration and the implementation of our test class are in a .cpp file, we also need to include the generated moc file to make Qt's introspection work. */ /*! \example tutorial4 \previouspage {Chapter 3: Simulating GUI Events}{Chapter 3} \contentspage {Qt Test Tutorial}{Contents} \nextpage {Chapter 5: Writing a Benchmark}{Chapter 5} \title Chapter 4: Replaying GUI Events In this chapter, we will show how to simulate a GUI event, and how to store a series of GUI events as well as replay them on a widget. The approach to storing a series of events and replaying them is quite similar to the approach explained in \l {Chapter 2: Data Driven Testing}{chapter 2}. All you need to do is to add a data function to your test class: \snippet tutorial4/testgui.cpp 0 \section1 Writing the Data Function As before, a test function's associated data function carries the same name, appended by \c{_data}. \snippet tutorial4/testgui.cpp 1 First, we define the elements of the table using the QTest::addColumn() function: A list of GUI events, and the expected result of applying the list of events on a QWidget. Note that the type of the first element is \l QTestEventList. A QTestEventList can be populated with GUI events that can be stored as test data for later usage, or be replayed on any QWidget. In our current data function, we create two \l {QTestEventList} elements. The first list consists of a single click to the 'a' key. We add the event to the list using the QTestEventList::addKeyClick() function. Then we use the QTest::newRow() function to give the data set a name, and stream the event list and the expected result into the table. The second list consists of two key clicks: an 'a' with a following 'backspace'. Again we use the QTestEventList::addKeyClick() to add the events to the list, and QTest::newRow() to put the event list and the expected result into the table with an associated name. \section1 Rewriting the Test Function Our test can now be rewritten: \snippet tutorial4/testgui.cpp 2 The TestGui::testGui() function will be executed two times, once for each entry in the test data that we created in the associated TestGui::testGui_data() function. First, we fetch the two elements of the data set using the \l QFETCH() macro. \l QFETCH() takes two arguments: the data type of the element and the element name. Then we create a QLineEdit, and apply the list of events on that widget using the QTestEventList::simulate() function. Finally, we use the QCOMPARE() macro to check if the line edit's text is as expected. As before, to make our test case a stand-alone executable, the following two lines are needed: \snippet tutorial4/testgui.cpp 3 The QTEST_MAIN() macro expands to a simple main() method that runs all the test functions, and since both the declaration and the implementation of our test class are in a .cpp file, we also need to include the generated moc file to make Qt's introspection work. */ /*! \example tutorial5 \previouspage {Chapter 4: Replaying GUI Events}{Chapter 4} \contentspage {Qt Test Tutorial}{Contents} \title Chapter 5: Writing a Benchmark In this final chapter we will demonstrate how to write benchmarks using Qt Test. \section1 Writing a Benchmark To create a benchmark we extend a test function with a QBENCHMARK macro. A benchmark test function will then typically consist of setup code and a QBENCHMARK macro that contains the code to be measured. This test function benchmarks QString::localeAwareCompare(). \snippet tutorial5/benchmarking.cpp 0 Setup can be done at the beginning of the function, the clock is not running at this point. The code inside the QBENCHMARK macro will be measured, and possibly repeated several times in order to get an accurate measurement. Several \l {testlib-benchmarking-measurement}{back-ends} are available and can be selected on the command line. \section1 Data Functions Data functions are useful for creating benchmarks that compare multiple data inputs, for example locale aware compare against standard compare. \snippet tutorial5/benchmarking.cpp 1 The test function then uses the data to determine what to benchmark. \snippet tutorial5/benchmarking.cpp 2 The "if (useLocaleCompare)" switch is placed outside the QBENCHMARK macro to avoid measuring its overhead. Each benchmark test function can have one active QBENCHMARK macro. \section1 External Tools Tools for handling and visualizing test data are available as part of the \l {qtestlib-tools} project. These include a tool for comparing performance data obtained from test runs and a utility to generate Web-based graphs of performance data. See the \l{qtestlib-tools Announcement}{qtestlib-tools announcement} for more information on these tools and a simple graphing example. */