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/*!
    \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 Qt Creator, 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

    You can use a Qt Creator wizard to create a project that contains Qt tests
    and build and run them directly from Qt Creator. For more information, see
    \l {Qt Creator: Running Autotests}{Running Autotests}.

    \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, you can define the following private slots that are \e not
    treated as test functions. When present, 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{initTestCase_data()} will be called to create a global test data table.
    \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

    Use \c initTestCase() for preparing the test. Every test should leave the
    system in a usable state, so it can be run repeatedly. Cleanup operations
    should be handled in \c cleanupTestCase(), so they get run even if the test
    fails.

    Use \c init() for preparing a test function. Every test function should
    leave the system in a usable state, so it can be run repeatedly. Cleanup
    operations should be handled in \c cleanup(), so they get run even if the
    test function fails and exits early.

    Alternatively, you can use RAII (resource acquisition is initialization),
    with cleanup operations called in destructors, to ensure they happen when
    the test function returns and the object moves out of scope.

    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

    Finally, if the test class has a static public \c{void initMain()} method,
    it is called by the QTEST_MAIN macros before the QApplication object
    is instantiated. This was added in 5.14.

    For more examples, refer to the \l{Qt Test Tutorial}.

    \section1 Increasing Test Function Timeout

    QtTest limits the run-time of each test to catch infinite loops and similar
    bugs. By default, any test function call will be interrupted after five
    minutes. For data-driven tests, this applies to each call with a distinct
    data-tag. This timeout can be configured by setting the \c QTEST_FUNCTION_TIMEOUT
    environment variable to the maximum number of milliseconds that is acceptable
    for a single call to take. If a test takes longer than the configured timeout,
    it is interrupted, and \c qFatal() is called. As a result, the test aborts by
    default, as if it had crashed.

    To set \c QTEST_FUNCTION_TIMEOUT from the command line on Linux or macOS, enter:

    \badcode
    QTEST_FUNCTION_TIMEOUT=900000
    export QTEST_FUNCTION_TIMEOUT
    \endcode

    On Windows:
    \badcode
    SET QTEST_FUNCTION_TIMEOUT=900000
    \endcode

    Then run the test inside this environment.

    Alternatively, you can set the environment variable programmatically in the
    test code itself, for example by calling, from the
    \l{Creating a Test}{initMain()} special method of your test class:

    \badcode
    qputenv("QTEST_FUNCTION_TIMEOUT", "900000");
    \endcode

    To calculate a suitable value for the timeout, see how long the test usually
    takes and decide how much longer it can take without that being a symptom of
    some problem. Convert that longer time to milliseconds to get the timeout value.
    For example, if you decide that a test that takes several minutes could
    reasonably take up to twenty minutes, for example on a slow machine,
    multiply \c{20 * 60 * 1000 = 1200000} and set the environment variable to
    \c 1200000 instead of the \c 900000 above.

    \if !defined(qtforpython)
    \section1 Building a Test

    You can build an executable that contains one test class that typically
    tests one class of production code. However, usually you would want to
    test several classes in a project by running one command.

    See \l {Chapter 1: Writing a Unit Test}{Writing a Unit Test} for a step by
    step explanation.

    \section2 Building with CMake and CTest

    You can use \l {Building with CMake and CTest} to create a test.
    \l{https://cmake.org/cmake/help/latest/manual/ctest.1.html}{CTest} enables
    you to include or exclude tests based on a regular expression that is
    matched against the test name. You can further apply the \c LABELS property
    to a test and CTest can then include or exclude tests based on those labels.
    All labeled targets will be run when \c {test} target is called on the
    command line.

    \note On Android, if you have one connected device or emulator, tests will
    run on that device. If you have more than one device connected, set the
    environment variable \c {ANDROID_DEVICE_SERIAL} to the
    \l {Android: Query for devices}{ADB serial number} of the device that
    you want to run tests on.

    There are several other advantages with CMake. For example, the result of
    a test run can be published on a web server using CDash with virtually no
    effort.

    CTest scales to very different unit test frameworks, and works out of the
    box with QTest.

    The following is an example of a CMakeLists.txt file that specifies the
    project name and the language used (here, \e mytest and C++), the Qt
    modules required for building the test (Qt5Test), and the files that are
    included in the test (\e tst_mytest.cpp).

    \quotefile code/doc_src_cmakelists.txt

    For more information about the options you have, see \l {Build with CMake}.

    \section2 Building with qmake

    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

    To prevent the test from being installed to your target, add the
    additional line:

    \snippet code/doc_src_qtestlib.pro 3

    See the \l{Building a Testcase}{qmake manual} for
    more information about \c{make check}.

    \section2 Building with Other Tools

    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}.

    \endif

    \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 row called \c
    zero (if the specified test data doesn't exist, the associated test
    will fail and the available data tags are reported).

    \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, \c junitxml or \c tap).  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 -junitxml \br
    Outputs results as an JUnit XML document.
    \li \c -csv \br
    Outputs results as comma-separated values (CSV). This mode is only suitable for
    benchmarks, since it suppresses normal pass/fail messages.
    \li \c -teamcity \br
    Outputs results in TeamCity format.
    \li \c -tap \br
    Outputs results in Test Anything Protocol (TAP) format.
    \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, \c -teamcity,
    \c -junitxml or \c -tap 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.
    On Windows, it re-enables the Windows Error Reporting dialog, which is
    turned off by default. This is useful for debugging crashes.

    \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 Qt Test Environment Variables

    You can set certain environment variables in order to affect
    the execution of an autotest:

    \list
    \li \c QTEST_DISABLE_CORE_DUMP \br
    Setting this variable to a non-zero value will disable the generation
    of a core dump file.
    \li \c QTEST_DISABLE_STACK_DUMP \br
    Setting this variable to a non-zero value will prevent Qt Test from
    printing a stacktrace in case an autotest times out or crashes.
    \li \c QTEST_FATAL_FAIL \br
    Setting this variable to a non-zero value will cause a failure in
    an autotest to immediately abort the entire autotest. This is useful
    to e.g. debug an unstable or intermittent failure in a test, by
    launching the test in a debugger. Support for this variable has been
    added in Qt 6.1.
    \endlist

    \section1 Creating a Benchmark

    To create a benchmark, follow the instructions for creating a test and then add a
    \l QBENCHMARK macro or \l QTest::setBenchmarkResult() to the test function that
    you want to benchmark. In the following code snippet, the macro is used:

    \snippet code/doc_src_qtestlib.cpp 12

    A test function that measures performance should contain either a single
    \c QBENCHMARK macro or a single call to \c setBenchmarkResult(). Multiple
    occurrences make no sense, because only one performance result can be
    reported per test function, or per data tag in a data-driven setup.

    Avoid changing the test code that forms (or influences) the body of a
    \c QBENCHMARK macro, or the test code that computes the value passed to
    \c setBenchmarkResult(). Differences in successive performance results
    should ideally be caused only by changes to the product you are testing.
    Changes to the test code can potentially result in misleading report of
    a change in performance. If you do need to change the test code, make
    that clear in the commit message.

    In a performance test function, the \c QBENCHMARK or \c setBenchmarkResult()
    should be followed by a verification step using \l QCOMPARE(), \l QVERIFY(),
    and so on. You can then flag a performance result as \e invalid if another
    code path than the intended one was measured. A performance analysis tool
    can use this information to filter out invalid results.
    For example, an unexpected error condition will typically cause the program
    to bail out prematurely from the normal program execution, and thus falsely
    show a dramatic performance increase.

    \section2 Selecting the Measurement Back-end

    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, \macos, Linux, many UNIX-like systems.
    \row \li Event Counter
         \li -eventcounter
         \li All platforms
    \row \li Valgrind Callgrind
         \li -callgrind
         \li Linux (if installed)
    \row \li Linux Perf
         \li -perf
         \li Linux
    \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).

    The Linux Performance Monitoring solution is available only on Linux and
    provides many different counters, which can be selected by passing an
    additional option \c {-perfcounter countername}, such as \c {-perfcounter
    cache-misses}, \c {-perfcounter branch-misses}, or \c {-perfcounter
    l1d-load-misses}. The default counter is \c {cpu-cycles}. The full list of
    counters can be obtained by running any benchmark executable with the
    option \c -perfcounterlist.

    \note
    \list
    \li Using the performance counter may require enabling access to non-privileged
        applications.
    \li Devices that do not support high-resolution timers default to
        one-millisecond granularity.
    \endlist

    See \l {Chapter 5: Writing a Benchmark}{Writing a Benchmark} in the Qt Test
    Tutorial for more benchmarking examples.

    \section1 Using Global Test Data

    You can define \c{initTestCase_data()} to set up a global test data table.
    Each test is run once for each row in the global test data table. When the
    test function itself \l{Chapter 2: Data Driven Testing}{is data-driven},
    it is run for each local data row, for each global data row. So, if there
    are \c g rows in the global data table and \c d rows in the test's own
    data-table, the number of runs of this test is \c g times \c d.

    Global data is fetched from the table using the \l QFETCH_GLOBAL() macro.

    The following are typical use cases for global test data:

    \list
        \li Selecting among the available database backends in QSql tests to run
            every test against every database.
        \li Doing all networking tests with and without SSL (HTTP versus HTTPS)
            and proxying.
        \li Testing a timer with a high precision clock and with a coarse one.
        \li Selecting whether a parser shall read from a QByteArray or from a
            QIODevice.
    \endlist

    For example, to test each number provided by \c {roundTripInt_data()} with
    each locale provided by \c {initTestCase_data()}:

    \snippet code/src_qtestlib_qtestcase_snippet.cpp 31

    On the command-line of a test you can pass the name of a function (with no
    test-class-name prefix) to run only that one function's tests. If the test
    class has global data, or the function is data-driven, you can append a data
    tag, after a colon, to run only that tag's data-set for the function. To
    specify both a global tag and a tag specific to the test function, combine
    them with a colon between, putting the global data tag first. For example

    \snippet code/doc_src_qtestlib.qdoc 6

    will run the \c zero test-case of the \c roundTripInt() test above (assuming
    its \c TestQLocale class has been compiled to an executable \c testqlocale)
    in each of the locales specified by \c initTestCase_data(), while

    \snippet code/doc_src_qtestlib.qdoc 7

    will run all three test-cases of \c roundTripInt() only in the C locale and

    \snippet code/doc_src_qtestlib.qdoc 8

    will only run the \c zero test-case in the C locale.

    Providing such fine-grained control over which tests are to be run can make
    it considerably easier to debug a problem, as you only need to step through
    the one test-case that has been seen to fail.

*/

/*!
    \page qtest-tutorial.html
    \brief A short introduction to testing with Qt Test.
    \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}
    \li \l {Chapter 6: Skipping Tests with QSKIP}{Skipping Tests}
    \endlist

*/


/*!
    \example tutorial1

    \nextpage {Chapter 2: Data Driven Testing}{Chapter 2}

    \title Chapter 1: Writing a Unit Test
    \brief How to write 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 \c 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}
    \nextpage {Chapter 3: Simulating Gui Events}{Chapter 3}

    \title Chapter 2: Data Driven Testing
    \brief How to create data driven tests.

    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 and used in the test log to identify the data set.
    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

    When data is streamed into the row, each datum is asserted to match
    the type of the column whose value it supplies. If any assertion fails,
    the test is aborted.

    \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}
    \nextpage {Chapter 4: Replaying GUI Events}{Chapter 4}

    \title Chapter 3: Simulating GUI Events
    \brief Howe to simulate 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}
    \nextpage {Chapter 5: Writing a Benchmark}{Chapter 5}

    \title Chapter 4: Replaying GUI Events
    \brief How to replay 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}
    \nextpage {Chapter 6: Skipping Tests with QSKIP}{Chapter 6}

    \title Chapter 5: Writing a Benchmark
    \brief How to write 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.

*/
/*!
    \page qttestlib-tutorial6.html

    \previouspage {Chapter 5: Writing a Benchmark}{Chapter 5}

    \title Chapter 6: Skipping Tests with QSKIP
    \brief How to skip tests in certain cases.

    \section2 Using QSKIP(\a description) in a test function

    If the \l QSKIP() macro is called from a test function, it stops
    the execution of the test without adding a failure to the test log.
    It can be used to skip tests that are certain to fail. The text in
    the QSKIP \a description parameter is appended to the test log,
    and explains why the test was not carried out.

    QSKIP can be used to skip testing when the implementation is not yet
    complete or not supported on a certain platform. When there are known
    failures, it is recommended to use \l QEXPECT_FAIL, so that the test is
    always completely executed.

    Example of QSKIP in a test function:

    \snippet code/doc_src_qtqskip_snippet.cpp 0

    In a data-driven test, each call to QSKIP() skips only the current
    row of test data. If the data-driven test contains an unconditional
    call to QSKIP, it produces a skip message for each row of test data.

    \section2 Using QSKIP in a _data function

    If called from a _data function, the QSKIP() macro stops
    execution of the _data function. This prevents execution of the
    associated test function.

    See below for an example:

    \snippet code/doc_src_qtqskip.cpp 1

    \section2 Using QSKIP from initTestCase() or initTestCase_data()

    If called from \c initTestCase() or \c initTestCase_data(), the
    QSKIP() macro will skip all test and _data functions.

    \sa {Select Appropriate Mechanisms to Exclude Tests}
*/
