[SOLVED] QXcbConnection: Could not connect to display [Qt] [Jenkins]

Nielske87

I’m having some problems implementing a simple GuiTest (that uses QTestLib) in Jenkins. In a terminal I can execute the following command:

@./tst_testgui -xunitxml > testresult.xml@

This command generates the following .xml file:

@
<?xml version="1.0" encoding="UTF-8" ?>
<testsuite errors="0" failures="0" tests="3" name="TestGui">
<properties>
<property value="5.0.2" name="QTestVersion"/>
<property value="5.0.2" name="QtVersion"/>
</properties>
<testcase result="pass" name="initTestCase"/>
<testcase result="pass" name="testGui"/>
<testcase result="pass" name="cleanupTestCase"/>
<system-err/>
</testsuite>@

In Jenkins I’m trying to do the same by executing the same command in an Execute Shell, but after building the project (works fine) and then executing de command:

@./tst_testgui -xunitxml > testresult.xml@

I get the following message in Jenkins:

QXcbConnection: Could not connect to display
Aborted (core dumped)
Build step ‘Execute shell’ marked build as failure
Finished: FAILURE

Does somebody know what could be the problem?

I’m running Jenkins (for the moment) on my localhost and I don’t know if I have a graphic server.
Where can I check if I’m using a graphic server in Jenkins?

BTW: There is an empty testresult.xml generated in de workspace folder.

Grtz. Niels

Nielske87

The GuiTest I made is an example project from Qt itself and looks like this:
@#include <QString>
#include <QStringList>
#include <QtTest>
#include <QLineEdit>

#include <QApplication>
#include <QTextEdit>
#include <QtGui>
#include <QPushButton>
#include <QVBoxLayout>
#include <QMessageBox>

class TestGui : public QObject
{
Q_OBJECT

private slots:
void testGui();

};

void TestGui::testGui()
{
QLineEdit lineEdit;
QTest::keyClicks(&lineEdit, "hello world");
QCOMPARE(lineEdit.text(), QString("hello world"));
}

QTEST_MAIN(TestGui)

#include "tst_testgui.moc"@

The output in QtCreator after running looks like this:

********** Start testing of TestGui **********
Config: Using QTest library 5.0.2, Qt 5.0.2
PASS : TestGui::initTestCase()
PASS : TestGui::testGui()
PASS : TestGui::cleanupTestCase()
Totals: 3 passed, 0 failed, 0 skipped
********* Finished testing of TestGui *********

When I change:
@QTEST_MAIN(TestGui)@

In:
@QTEST_APPLESS_MAIN(TestGui)@

The output in QtCreator looks like this:

********* Start testing of TestGui *********
Config: Using QTest library 5.0.2, Qt 5.0.2
PASS : TestGui::initTestCase()
QFATAL : TestGui::testGui() QWidget: Must construct a QApplication before a QPaintDevice
FAIL! : TestGui::testGui() Received a fatal error.
Loc: [Unknown file(0)]
Totals: 1 passed, 1 failed, 0 skipped
********* Finished testing of TestGui *********
The program has unexpectedly finished.

But the error in Jenkins is different now:

+ ./tst_testgui -xml
Aborted (core dumped)
Build step 'Execute shell' marked build as failure
Finished: FAILURE

Does anybody have an idea?

SGaist

Hi,

You are using GUI elements so you have to use QTEST_MAIN.

When running your application from Jenkins, are you sure that it can find all libraries and plugins ?

Nielske87

I think it does, because I can build and compile the project via Jenkins and I managed to make an UnitTest using CppUnit via the JUnit-plugin in an other project with (almost) the same configuration and that works perfect.

Via the terminal I can exucte the program (tst_testgui) but not with Jenkins.

Thnx for the fast response!

EDIT: I'm not using a plugin at the moment. I'm only using shell commands.

EDIT2: When try to execute the program via Jenkins from my home directory I get the same output as before:
+ /home/hotracodev/workspace/Focus/Experiment/TutorialGuiTest/tutorialGuiTest/tst_testgui
QXcbConnection: Could not connect to display
Aborted (core dumped)
Build step 'Execute shell' marked build as failure
Finished: FAILURE

SGaist

Yes you are: Qt 5's platform plugin which is using xcb in your case.

I don't know jenkins but you could try to see if sets somehow the environment variables before doing a test and if so how does it differ from your console environment variables

Nielske87

I managed to solve my problem.

The problem was in the configuration of Jenkins.
I needed to use an X-server on my Jenkins machine to run my GUI programs.

#SOLVED

SGaist

Great you found out !

Can you update your thread's title to solved ? So other forum users may know a solution has been found :)