1630485 - Intermittent comm/calendar/test/browser/browser_todayPane.js | uncaught exception - TypeError: can't access property "currentTask", this.tree is null at modifyItems@chrome://calendar/content/calendar-task-tree-view.js:88:19

Status: RESOLVED FIXED

(Calendar :: Calendar Frontend, defect, P5)

Description

[Treeherder Bug Filer]

Filed by: geoff [at] darktrojan.net
Parsed log: https://treeherder.mozilla.org/logviewer.html#?job_id=297831810&repo=comm-central
Full log: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/WWJ8vr9YT3emqe7t0EDhYg/runs/0/artifacts/public/logs/live_backing.log

---

Comment 1

[Geoff Lankow (:darktrojan) [PTO, back 9 Feb]]

Attachment: 1630485-this-tree-is-null-1.diff

I don't know how we end up with a tree view not attached to a tree, the only explanations I have are that somehow the tree's been removed from the DOM or a new view has been set on it. I can't see how that either of those are possible.

I also can't see why this test is only failing after 16:00 UTC, but it seems that is the case. I can't test this patch properly right now if that really is the case.

Comment 2

[Geoff Lankow (:darktrojan) [PTO, back 9 Feb]]

Attachment: 1630485-move-timezones-test-1.diff

This patch moves browser_timezones.js into a folder of its own. I suspect it is part of the problem with browser_todayPane.js, for two reasons: the weird "this only happens at certain times of day" thing, and because the failure doesn't seem to happen on debug builds, and browser_timezones.js doesn't run on debug builds.

Ideally I'd land these patches separately to confirm one or the other fixes this bug.

Comment 3

[Paul Morris [:pmorris]]

Comment on attachment 9140929 [details] [diff] [review]
1630485-this-tree-is-null-1.diff

Review of attachment 9140929 [details] [diff] [review]:
-----------------------------------------------------------------

r+ LGTM. Strange bug. One suggestion for the comment, if you think it would help.

::: calendar/base/content/calendar-task-tree.js
@@ +458,5 @@
>          operation: null,
>  
>          onOperationComplete(opCalendar, status, operationType, id, dateTime) {
> +          if (!this.tree.mTreeView.tree) {
> +            // Looks like we've been disconnected from the DOM, there's no point in continuing.

Maybe add this bug number to the comment?

Comment 4

[Paul Morris [:pmorris]]

Comment on attachment 9140930 [details] [diff] [review]
1630485-move-timezones-test-1.diff

Review of attachment 9140930 [details] [diff] [review]:
-----------------------------------------------------------------

r+ LGTM.  (As an aside this test always causes trouble when I run it locally.  It intermittently fails to select some of the timezones in the event timezone dialog menu, gets stuck.  I have it on my list to try and fix that.)

::: calendar/test/browser/timezones/browser_timezones.js
@@ -50,5 @@
>  ];
>  
>  add_task(async function testTimezones1_SetGMT() {
>    Services.prefs.setStringPref("calendar.timezone.local", "Europe/London");
> -  await setCalendarView("day");

Can you say more about why this change?  Just curious.  Also, you could drop the "async" from the function.

Comment 5

[Geoff Lankow (:darktrojan) [PTO, back 9 Feb]]

(In reply to Paul Morris [:pmorris] from comment #4)

• await setCalendarView("day");

Can you say more about why this change? Just curious.

The test will always start in the day view, unless we add more tests to this folder. It was insurance that we were in the right view to begin with. Also, the setCalendarView function is in the head.js file of the folder this used to be in, which we can't easily use from here.

I'm going to check this patch in but not the other, to see if it makes a difference by itself.

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/comm-central/rev/7ef1b81d70f7
Move browser_timezones.js to a folder of its own. r=pmorris

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/comm-central/rev/01f1041e43c5
Stop trying to refresh a task tree that no longer exists. r=pmorris

Comment 8

[Intermittent Failures Robot]

32 failures in 4528 pushes (0.007 failures/push) were associated with this bug in the last 7 days.

** This failure happened more than 30 times this week! Resolving this bug is a high priority. **

** Try to resolve this bug as soon as possible. If unresolved for 2 weeks, the affected test(s) may be disabled. **

Repository breakdown:

• comm-central: 32

Platform breakdown:

• windows7-32: 6
• macosx1014-64: 7
• linux32: 6
• linux64: 7
• windows10-64: 6

For more details, see:
https://treeherder.mozilla.org/intermittent-failures.html#/bugdetails?bug=1630485&startday=2020-04-13&endday=2020-04-19&tree=all