1698842 - Prevent TargetCommand from notifying about new target that are already destroyed

Status: RESOLVED FIXED

(DevTools :: Framework, defect)

Description

[Alexandre Poirot [:ochameau]]

When trying to run devtools/client/framework/test/browser_toolbox_backward_forward_navigation.js test with patches from bug 1631451,
the test often fails with fission enabled because various onTargetAvailable function get called with an already destroyed target front.

This happens because the target is destroyed while TargetComment await for target attach and initialize thread front.
https://searchfox.org/mozilla-central/source/devtools/shared/commands/target/target-command.js#165-181

We should check that before calling emitAsync and call all the onTargetAvailable, that the target front is still usable.

Comment 1

[Alexandre Poirot [:ochameau]]

Attachment: Bug 1698842 - [devtools] Avoid notifying about already destroyed targets from TargetCommand.

This helps browser_toolbox_backward_forward_navigation.js passing with fission enabled.

Comment 2

[Alexandre Poirot [:ochameau]]

Attachment: Bug 1698842 - [devtools] Avoid a few cases where targetFront is null during a client side target switching.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/55166c719cd2
[devtools] Avoid notifying about already destroyed targets from TargetCommand. r=nchevobbe
https://hg.mozilla.org/integration/autoland/rev/0d9035ed5c50
[devtools] Avoid a few cases where targetFront is null during a client side target switching. r=nchevobbe

Comment 4

[Cosmin Sabou [:CosminS]]

Backed out for causing devtools and xpcshell failures.

Push with failures: https://treeherder.mozilla.org/jobs?repo=autoland&resultStatus=testfailed%2Cbusted%2Cexception%2Cretry%2Cusercancel&revision=0d9035ed5c50b569d09fab60d4e64c16c362de10&selectedTaskRun=B6cCh9skSbiADrrmcp1q7A.0

Failure logs:
https://treeherder.mozilla.org/logviewer?job_id=333573797&repo=autoland
https://treeherder.mozilla.org/logviewer?job_id=333573618&repo=autoland

Backlout link: https://hg.mozilla.org/integration/autoland/rev/0f098000e0e79fbe1b1f4542de062b7429454d49

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/b791ebfc50aa
[devtools] Avoid notifying about already destroyed targets from TargetCommand. r=nchevobbe
https://hg.mozilla.org/integration/autoland/rev/cfa1cd1f0ad0
[devtools] Avoid a few cases where targetFront is null during a client side target switching. r=nchevobbe

Comment 6

[Atila Butkovits]

https://hg.mozilla.org/mozilla-central/rev/b791ebfc50aa
https://hg.mozilla.org/mozilla-central/rev/cfa1cd1f0ad0