1628626 - Can't clear messages in Browser Console/Browser Toolbox if target was destroyed

Status: VERIFIED FIXED

(DevTools :: Console, defect, P1)

Description

[Nicolas Chevobbe [:nchevobbe]]

Steps to reproduce

1. In firefox, navigate to https://nchevobbe.github.io/demo/console-test-app.html
2. Click on the console.log button to log some messages
3. Open the browser console
4. Close the https://nchevobbe.github.io/demo/console-test-app.html tab
5. In the browser console, try to clear the output

Expected results

The output gets cleared

Actual results

The output isn't cleared, and we get the following message:

Error: Can not send request 'release' because front 'obj' is already destroyed.

---

Closing the tab is probably destroying the target, which means we release all the related fronts and actors. But then, when clearing the output, we'll try to release the fronts for the rendered objects, which may already be destroyed.

Comment 1

[Nicolas Chevobbe [:nchevobbe]]

Attachment: Bug 1628626 - Fix issue when clearing output with messages from destroyed targets. r=jdescottes.

With the new architecture, it might happen that a message (and the ObjectFronts
it holds), are still displayed in the Browser Console / Browser Toolbox Console,
even if the target of those object fronts was destroyed.
In such case, when the user would legimitely try to clear the console, we'd try
to release the fronts that were already destroyed, which would throw an exception
and leave the console in a bad state.
This patch simply check that the fronts are still alive when we try to release
them, and adds a test (that was failing without that patch, with fission ON) for
the Browser Console.

Comment 2

[Chris Peterson [:cpeterson]]

Tracking Fission DevTools bugs for Fission Nightly (M6) milestone

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/6b974e1bf99a
Fix issue when clearing output with messages from destroyed targets. r=jdescottes.

Comment 4

[Stefan Hindli [:stefan_hindli]]

https://hg.mozilla.org/mozilla-central/rev/6b974e1bf99a

Comment 5

[Alexandru Trif, Desktop QA [:atrif]]

Reproduced the issue using Firefox 77.0a1 (20200409131623) on Windows 10x64.
The issue is verified fixed with Firefox 77.0.1 (20200602222727) and 78.0.1 (20200630195452) on Windows 10x64.