Redirect QTest Output To Log File

QtTest classes are created by subclassing QObject class and adding private slots into derived QObject class. Every private slot is treated as a testfunction and executed by QTest::qExec() function.
Sample project started as a QT Console Application and contains main.cpp, TestString.h and TestString.cpp files.
Project Directory Structure in Qt Creator IDE :



LogQTestOutputToFile.pro is the project configuration file and contains:

QT       += testlib core
TARGET = LogQTestOutputToFile
TEMPLATE = app
SOURCES += main.cpp \
    TestString.cpp
HEADERS  += TestString.h

QT += testlib

line which is used to include testlib dependencies into project.

TestString.h file contains private slots which are aimed to test mainly toUpper() behavior of String class.

#include <QtTest/QtTest>
#include <QString>
#include <QObject>

class TestString: public QObject
{
    Q_OBJECT
private slots:
    void initTestCase();
    void toUpper();
    void cleanupTestCase();
};

initTestCase() and cleanupTestCase() private slots are executed by the testing framework and used to initialize and release resources; respectively.

TestString.cpp file contains implementation details for the private slots declared in TestString.h file.

#include "TestString.h"

void TestString::initTestCase()
{
    qDebug("called before everything else, initialize your resources");
}

void TestString::toUpper()
{
    QString str = "Hello";
    QCOMPARE(str.toUpper(), QString("HELLO"));
}

void TestString::cleanupTestCase()
{
    qDebug("called after toUpper(), release allocated resources here");
}

Because this a QT Console Application, main.cpp file contains only main() function which calls QTest::qExec(&testString, testCmd) function to execute testfunctions in the specified test object.

#include <QApplication>
#include <QStringList>
#include <QDir>
#include "TestString.h"
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QStringList testCmd;
    QDir qtestLogDir;
    qtestLogDir.mkdir("UnitTest_Results");
    testCmd<<" "<<"-o"<<"UnitTest_Results/QTestString_log.txt";
    TestString testString;
    QTest::qExec(&testString, testCmd);
    return a.exec();
}

When you run the application, test execution output is displayed at QT Creator Application Output Window. In order to redirect testfunction output to specified log file; output directory and log file name information are passed as argument to QTest::qExec(&testString, testCmd) function.

testCmd<<" "<<"-o"<<"UnitTest_Results/QTestString_log.txt";

command line argument redirects output to UnitTest_Results/QTestString_log.txt file.

QTestString_log.txt file can be found under LogQTestOutputToFile/UnitTest_Results folder.