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/****************************************************************************
**
** Copyright (C) 2019 The Qt Company Ltd.
** Copyright (C) 2016 Intel Corporation.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
** Commercial License Usage
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** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Free Documentation License Usage
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
** the GNU Free Documentation License version 1.3 requirements
** will be met: https://www.gnu.org/licenses/fdl-1.3.html.
** $QT_END_LICENSE$
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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}.
\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.
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 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, \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
*/
/*!
\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 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 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 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.
*/
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