2071238 - Intermittent browser_dbg-event-breakpoints.js | Test timed out | leaked 1 window(s)

Status: RESOLVED FIXED

(DevTools :: Debugger, defect)

Description

[Florian Quèze [:florian]]

The blackboxed round of browser_dbg-event-breakpoints.js invokes timerHandler, waits 100ms and asserts that the debugger did not pause. The page's timer is 50ms, but on a slow worker it fired at 114ms, after the round had unblackboxed the source. The timer.timeout.fire breakpoint then pauses the thread behind the test's back.

The next round enables the beforeunload breakpoint and reloads. That navigation runs inside the stray pause, where the debuggee no-execute guard refuses the handler, so the breakpoint never hits and the test times out with the toolbox window leaked. Turning the round's breakpoints off before unblackboxing fixes it.

Comment 1

[Florian Quèze [:florian]]

Attachment: Bug 2071238 - [devtools] Retire the blackboxed round's event breakpoints before unblackboxing, r=#devtools-reviewers.

The XHR load and the 50ms timer the blackboxed round starts can land after its
wait(100), and unblackboxing first lets the timer pause the thread. The next
round's navigation then runs "beforeunload" inside that pause, where
EnterDebuggeeNoExecute refuses the debuggee, so the breakpoint the test waits
for never hits and the test times out with the toolbox window leaked.

Bug 2070797 removed this test's macOS skips on the strength of a mechanism that
is not macOS-specific; that still wants a macOS debug rebuild push for a real
denominator.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/ff977d7c66bb
https://hg.mozilla.org/integration/autoland/rev/f561c5285c99
[devtools] Retire the blackboxed round's event breakpoints before unblackboxing, r=devtools-reviewers,nchevobbe.

Comment 3

[amarc]

https://hg.mozilla.org/mozilla-central/rev/f561c5285c99