1179684 - [gui] list index out of range error when stopping a bisection

Status: RESOLVED FIXED

(Testing :: mozregression, defect)

Description

[Julien Pagès (:parkouss)]

I was playing around with the gui, started a download then clicked on the toolbar button:

> python gui/build.py run
> Executing `/home/jp/dev/mozregression/venv/bin/python mozregui/main.py`
> Traceback (most recent call last):
>   File "/home/jp/dev/mozregression/gui/mozregui/report.py", line 129, in download_progress
>     item = self.items[-1]
> IndexError: list index out of range

This is not blocking at all, as it have no impact, but it would be cool to handle this possible error.

I suppose it may happen because even if we stop the bisection, the download is in a thread and may not stop immediately - in this case it had the time to trigger a last signal, but after we removed the items in the view.

I highly suspect that moving:

https://github.com/mozilla/mozregression/blob/9e54f073894b2f053ea56141fd988915249dd794/gui/mozregui/main.py#L98

before we call stop on the bisect runner will fix this.

Comment 1

[MikeLing]

(In reply to Julien Pagès from comment #0)

Hi Julien,

Did you still have this problem on your gui? I just try it on locally and haven't see the same output as you given.

Comment 2

[Julien Pagès (:parkouss)]

It is an intermittent bug. When we stop the bisection, we ask for the download to stop (calling bisect_runner.stop(False)) then we clear the report view and detach it to not get incoming signals anymore. But it appears that sometimes this fails

The logic would be rather to first clean the report view / disconnect it - then ask for the bisection to stop. This way we can't receive signals coming from the thread since we disconnected the signal reception before asking the end of the thread.

Is that clear enough ? Feel free to tackle this if you want! I think the solution I propose is good (comment 0), but this should be tested (just to be sure it still works good), and also it would be good if you agree on the logic I described here (I mean if that also make sense for you).

Comment 3

[MikeLing]

Attachment: PR for bug 1179684

Done~ Hope this PR can help :)

Comment 4

[Julien Pagès (:parkouss)]

Comment on attachment 8647494 [details] [review]
PR for bug 1179684

Thanks for this!

Comment 5

[Julien Pagès (:parkouss)]

Landed in https://github.com/mozilla/mozregression/commit/6cfc95c16413ec560a24853920d2c3d6f0cee8d0.