456653 - ASSERTION: Unexpected mutations happened. Check your match function!: '!debugMutationGuard.Mutated(0)'

Status: VERIFIED FIXED

(Core :: DOM: Core & HTML, defect)

Description

[Mats Palmgren (inactive)]

STEPS TO REPRODUCE
1. run the following mochitest in a debug build:
toolkit/content/tests/widgets/test_sorttemplate.xul

ACTUAL RESULT
###!!! ASSERTION: Unexpected mutations happened.  Check your match function!: '!debugMutationGuard.Mutated(0)', file /usr/moz/hg5/content/base/src/nsContentList.cpp, line 763
###!!! ASSERTION: Unexpected mutations happened.  Check your match function!: '!debugMutationGuard.Mutated(0)', file /usr/moz/hg5/content/base/src/nsContentList.cpp, line 810


EXPECTED RESULT


PLATFORMS AND BUILDS TESTED
Firefox trunk on Linux and MacOSX

Comment 1

[Boris Zbarsky [:bzbarsky]]

Fixing bug 450990 will fix this.

Comment 2

[[e-mail]]

(In reply to comment #1)
> Fixing bug 450990 will fix this.
How does that work when your content list includes a menu or tree, you only see already generated content (which works for me btw) in that case?

Comment 3

[Boris Zbarsky [:bzbarsky]]

enn is the right guy to ask that.

Comment 5

[Neil Deakin]

(In reply to comment #3)
> enn is the right guy to ask that.

Ask what?

Comment 6

[[e-mail]]

(In reply to comment #5)
> (In reply to comment #3)
> > enn is the right guy to ask that.
> Ask what?
Trees and menus still generate templated content lazily, right? Would you expect code such as tree.getElementsByTagName('treeitem') to generate the contents to ensure that it returns all the tree items, or only return those contents that have already been generated? Currently we do the former; if we should do the latter, does bug 450990 achieve that?

Comment 7

[Neil Deakin]

(In reply to comment #6)
> (In reply to comment #5)
> > (In reply to comment #3)
> > > enn is the right guy to ask that.
> > Ask what?
> Trees and menus still generate templated content lazily, right? Would you
> expect code such as tree.getElementsByTagName('treeitem') to generate the
> contents to ensure that it returns all the tree items, or only return those
> contents that have already been generated? Currently we do the former; if we
> should do the latter, does bug 450990 achieve that?

Content for closed menus and trees is not generated until they are opened. With the patch in bug 450990, all other content is generated right away when the template is first built.

Comment 8

[Serge Gautherie (:sgautherie)]

(In reply to comment #4)
> *** Bug 456307 has been marked as a duplicate of this bug. ***

[Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9.1b2pre) Gecko/20081021 SeaMonkey/2.0a2pre] (home, debug default) (W2Ksp4)

I confirm that bug 450990 fixed this bug as reported in bug 456307.

Comment 9

[Henrik Skupin [:whimboo][⌚️UTC+2]]

So lets mark it fixed. Can you verify Serge?

The mentioned mochitest from comment 0 runs without any assertion:

Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.1b2pre) Gecko/20081021 Minefield/3.1b2pre ID:20081021200750

Comment 10

[Serge Gautherie (:sgautherie)]

V.Fixed, per (2) previous comment(s).