moc file not found

[rpieket]

@Christian-Ehrlicher Thanks. I don't see that file. I'm using qmake. There is a generated makefile that is too large to attach.

[jsulm]

@rpieket said in moc file not found:

I'm using qmake

Then you can show the pro file

[rpieket]

@jsulm Here is the pro file:

QT = core testlib

CONFIG += c++17 cmdline

# You can make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
    tests.cpp

# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

[Christian Ehrlicher]

Why do you include testqstring.moc when your source file is tests.cpp?

[ChrisW67]

@Christian-Ehrlicher Beat me to it.

The qmake "magic" that generates a Makefile rule for moc when it sees this style of include requires that it matches on the base name of the source file concerned.

[rpieket]

The mismatch is due to my attempt to simplify before posting. This is my actual main file, named tests.cpp. And yes, both TestOneToOne and TestOneToMany have the Q_OBJECT macro.

#include <QCoreApplication>
#include <QTest>

#include "TestOneToOne.h"
#include "TestOneToMany.h"

int main(int argc, char *argv[])
{
    int status = 0;
    status |= QTest::qExec(new TestOneToOne, argc, argv);
    status |= QTest::qExec(new TestOneToMany, argc, argv);

    return status;
}

#include "TestOneToOne.moc"
#include "TestOneToMany.moc"

[Christian Ehrlicher]

There is no need for foo.moc files when it's in a header. Then qmake/cmake automatically creates and adds moc_foo.cpp files.

[rpieket]

@Christian-Ehrlicher Without the moc files, I get:

ld: Undefined symbols:
  vtable for TestOneToOne, referenced from:
      _main in tests.o
  vtable for TestOneToMany, referenced from:
      _main in tests.o

With the moc files, it was working until this afternoon. Somehow I broke something, but I don't know what.

[Christian Ehrlicher]

Please show a minmal, compileable example and move code into source files and not in headers. qmake will not generate a moc_foo.cpp when there is no corresponding source file.

[ChrisW67]

The headers need to be listed in the PRO file:

HEADERS += TestOneToOne.h TestOneToMany.h

and qmake re-run. The magic moc includes are not required.

Edit: Maybe @Christian-Ehrlicher has a point: a one-to-one header-source relationship.

[Christian Ehrlicher]

@ChrisW67 said in moc file not found:

Edit: Maybe @Christian-Ehrlicher has a point: a one-to-one header-source relationship

I'm not completely sure since I don't use qmake since 15 years or so but how else should qmake know that it has to moc those files.

[SGaist]

Hi,

You can see in this thread a way to put together multiple tests.

That said, it will break the output. You should really keep the one class per test file.

@Christian-Ehrlicher the moc file include is standard when you define classes in the implementation file. It has some other benefits.

This blog article gives a pretty good summary about them.

[rpieket]

Minimal code. First main.cpp

#include <QCoreApplication>
#include <QTest>
QTEST_MAIN(TestQString)

And qteststring.h:

#pragma once
#include <QObject>
class TestQString: public QObject
{
    Q_OBJECT
private slots:
    void toUpper();
};

And qteststring.cpp:

#include <QTest>
#include "testqstring.h"
void TestQString::toUpper()
{
    QString str = "Hello";
    QCOMPARE(str.toUpper(), QString("HELLO"));
}
#include "testqstring.moc"

Finally the auto-generated .pro file:

QT = core

CONFIG += c++17 cmdline

# You can make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
        main.cpp \
        testqstring.cpp

# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

HEADERS += \
    testqstring.h

Resulting output:

make: *** No rule to make target `testqstring.moc', needed by `testqstring.o'.  Stop.
make: *** Waiting for unfinished jobs....
../Test_with_qmake/main.cpp:2:10: fatal error: 'QTest' file not found
#include <QTest>
         ^~~~~~~
1 error generated.
make: *** [main.o] Error 1
14:28:39: The process "/usr/bin/make" exited with code 2.
Error while building/deploying project Test_with_qmake (kit: Qt 6.6.1 for macOS)
When executing step "Make"

BTW I have never seen a moc_*.cpp, only a *.moc, and then only until yesterday afternoon, when it stopped working altogether.
Should I be using cmake? I have no preference. I'm using qmake only because it was the default.

[Christian Ehrlicher]

@rpieket said in moc file not found:

#include <QTest>

Then you should also add the correct qmake command as written in the documentation.

[ChrisW67]

@rpieket
The file names in the PRO file do not match those in your post.

Simple fix so that qmake now finds files.

A Qt test is just another Qt program, following all the same rules. It is just that the Test Lib writes main() for you to allow it to provide a lot of plumbing for you behind the scenes.
If you have the test class declaration in a separate header, as in this case, then that header should be listed in the PRO file HEADERS variable and not in the source file as an #include "blah.moc".

No longer get: make: *** No rule to make target `testqstring.moc', needed by `testqstring.o'. Stop

The QT variable in the PRO file needs QT += testlib so that the test Lib elements are included at compile and link time.
Rerun qmake after changing the PRO file

No longer get: ./Test_with_qmake/main.cpp:2:10: fatal error: 'QTest' file not found

Remaining problems are to do with the construction of the sources and not qmake.
main.cpp needs to #include "qteststring.h" so that the QTEST_MAIN macro expansion, which references TestString, knows what the class looks like.

Test compiles