running pyqt app event loop in secondary thread, using (Py)Qt6.5

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Hello,

I'm trying to establish a Python test methodology whereby a QApplication is
launched (and its event loop executed) in a secondary thread, while the
primary thread performs some "test scenario".
Summary: I'm unable to set this up, and it isn't clear why this isn't
working.

Details: please consider the attached test file (executed with `pytest -vs
qt-minimal-test,py`).

In this minimal test case, the actual test function body is empty. A
"fixture" function is used to set up the system, i.e. launch a thread to
construct the application showing only a "quit" button.

Consider these cases:

0.  run the above command, wait for the test passing being reported on the
console, then click the "quit" button. This appears to be working as
expected.

1. run the above command, but click the "quit" button immediately. Thus
results in the error message `QObject::killTimer: Timers cannot be stopped
from another thread`,
followed by a segmentation fault

2. rather than just "yielding" to the test function, yield the application
object (so the test function can interact with it). No matter when you
click the "quit" button, the result is the same as in 1.

3. call `h.app.quit()` after he `yield` (i.e. as soon as the test function
completes). Result: the application becomes unresponsive, but doesn't stop

Any idea why the above happens ?

Many thanks for any help you can offer !



-- 

      ...ich hab' noch einen Koffer in Berlin...

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<div dir=3D"ltr"><div>Hello,</div><div><br></div><div>I&#39;m trying to est=
ablish a Python test methodology whereby a QApplication is launched (and it=
s event loop executed) in a secondary thread, while the primary thread perf=
orms some &quot;test scenario&quot;.</div><div>Summary: I&#39;m unable to s=
et this up, and it isn&#39;t clear why this isn&#39;t working.</div><div><b=
r></div><div>Details: please consider the attached test file (executed with=
 `pytest -vs qt-minimal-test,py`).<br></div><div><br></div><div>In this min=
imal test case, the actual test function body is empty. A &quot;fixture&quo=
t; function is used to set up the system, i.e. launch a thread to construct=
 the application showing only a &quot;quit&quot; button.<br></div><div><br>=
</div><div>Consider these cases:</div><div><br></div><div>0.=C2=A0 run the =
above command, wait for the test passing being reported on the console, the=
n click the &quot;quit&quot; button. This appears to be working as expected=
.</div><div><br></div><div>1. run the above command, but click the &quot;qu=
it&quot; button immediately. Thus results in the error message `<span style=
=3D"font-family:monospace"><span style=3D"color:rgb(0,0,0);background-color=
:rgb(255,255,255)">QObject::killTimer: Timers cannot be stopped from anothe=
r thread`,</span><br></span></div><div><span style=3D"font-family:monospace=
">
followed by a segmentation fault<br></span></div><div><span style=3D"font-f=
amily:monospace"><br></span></div><div><span style=3D"font-family:monospace=
">2. rather than just &quot;yielding&quot; to the test function, yield the =
application object (so the test function can interact with it). No matter w=
hen you click the &quot;quit&quot; button, the result is the same as in 1.<=
/span></div><div><span style=3D"font-family:monospace"><br></span></div><di=
v><span style=3D"font-family:monospace">3. call `h.app.quit()` after he `yi=
eld` (i.e. as soon as the test function completes). Result: the application=
 becomes unresponsive, but doesn&#39;t stop</span></div><div><span style=3D=
"font-family:monospace"><br></span></div><div><span style=3D"font-family:mo=
nospace">Any idea why the above happens ?<br></span></div><div><span style=
=3D"font-family:monospace"><br></span></div><div><span style=3D"font-family=
:monospace">Many thanks for any help you can offer !<br></span></div><div><=
br></div><div><br></div><div><br><span class=3D"gmail_signature_prefix">-- =
</span><br><div dir=3D"ltr" class=3D"gmail_signature" data-smartmail=3D"gma=
il_signature"><div dir=3D"ltr"><div><img src=3D"https://ci3.googleuserconte=
nt.com/mail-sig/AIorK4yh4RzsqlxV6irScDGRVZ8a7NRCh_INtpPsAHx2Y8v4Vu3VKsI54RF=
Ns3YRZk_2xTTtMMdSCzdNrf5XRUlmF4BkezmtZv-j5c3A4G0hEA"></div><div><pre>      =
...ich hab&#39; noch einen Koffer in Berlin...
</pre></div></div></div></div></div>

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