2060460 - moz:debugging fails to handle nested pauses correctly

Status: RESOLVED FIXED

(Remote Protocol :: WebDriver BiDi, defect, P3)

Description

[Julian Descottes [:jdescottes]]

Spotted while reviewing Bug 2041335.

The moz:debugging windowglobal module tracks the paused state via a single flag (#paused). We also store a single paused frame in messageHandler.debuggerEnvironment.

If a nested pause occurs (either through evaluating script while paused, or via a same process iframe), this model breaks because you can't cleanly resume only the top pause (prior to Bug 2041335, it would fail slightly differently: we would remain paused with no way to resume).

We should fix this by adding a depth counter and a stack of frames, as well as tests.

Comment 1

[Julian Descottes [:jdescottes]]

Khalid, would you be interested in picking up this follow up bug around breakpoints? It is a bit more involved but I'm happy to help in case you want to pick it up.

I will push a patch adding tests in any case.

Comment 2

[Julian Descottes [:jdescottes]]

Attachment: WIP: Bug 2060460 - [wdpsec] Add tests for nested paused with moz:debugging

Comment 3

[Khalid AlHaddad]

(In reply to Julian Descottes [:jdescottes] from comment #1)

Khalid, would you be interested in picking up this follow up bug around breakpoints? It is a bit more involved but I'm happy to help in case you want to pick it up.

I will push a patch adding tests in any case.

Yes, I would like to pick it up, and thank you!

Comment 4

[Julian Descottes [:jdescottes]]

Great! Assigning to you, I think you already know how to run wdspec tests right? Feel free to pull the tests attached to the bug and use them to check your fixes!

Comment 5

[Khalid AlHaddad]

Yes as well, so I will add the depth counter and stack of frames. I will also pull the tests from this bug to verify my fixes, and I will let you know if I run into any issues.

Comment 6

[Khalid AlHaddad]

Attachment: Bug 2060460 - Add depth counter and stack of frames to handle nested pauses in moz:debugging. r=jdescottes

Comment 7

[Julian Descottes [:jdescottes]]

Hi Khalid, can you request review on https://phabricator.services.mozilla.com/D316732 ?

Comment 8

[Khalid AlHaddad]

Hi Julian, done. I requested review.

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/31d2cf1564f5
https://hg.mozilla.org/integration/autoland/rev/2de58503718e
Add depth counter and stack of frames to handle nested pauses in moz:debugging. r=jdescottes

Comment 10

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/2de58503718e