qttestlib-tutorial1.qdoc

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// Copyright (C) 2023 The Qt Company Ltd.
// Copyright (C) 2016 Intel Corporation.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
/*!
    \page qttestlib-tutorial1-example.html
    \previouspage {Qt Test Tutorial}{Qt Test Tutorial Overview}
    \nextpage {Chapter 2: Data Driven Testing}{Chapter 2}
 
    \title Chapter 1: Writing a Unit Test
    \brief How to write a unit test.
 
    This first chapter demonstrates how to write a simple unit test and how to
    run the test case as a stand-alone executable.
 
    \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.
 
    \section1 Preparing the Stand-Alone Executable
 
    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 Building the Executable
 
    \include {building-examples.qdocinc} {building the executable} {tutorial1}
 
    \note If you're using windows, replace \c make with \c
    nmake or whatever build tool you use.
 
    \section1 Running the Executable
 
    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.
*/