384327 - Attempting to remove a CSS style rule results in errors

Status: RESOLVED DUPLICATE of bug 253354

(Other Applications :: DOM Inspector, defect)

Description

[Shawn Wilsher :sdwilsh]

Trying to remove a CSS style rule nets a few errors, and ends up crashing.  This might not be a DOMi bug.

WARNING: NS_ENSURE_TRUE(index != -1) failed: file /Developer/mozilla/layout/style/nsCSSStyleSheet.cpp, line 1113
###!!! ASSERTION: container didn't take ownership: 'Not Reached', file /Developer/mozilla/layout/style/nsCSSStyleRule.cpp, line 996
************************************************************
* Call to xpconnect wrapped JSObject produced this error:  *
[Exception... "Component returned failure code: 0x8000ffff (NS_ERROR_UNEXPECTED) [nsIDOMCSSStyleDeclaration.removeProperty]"  nsresult: "0x8000ffff (NS_ERROR_UNEXPECTED)"  location: "JS frame :: chrome://inspector/content/viewers/styleRules/styleRules.js :: doTransaction :: line 560"  data: no]
************************************************************
JavaScript error: , line 0: uncaught exception: [Exception... "Component returned failure code: 0x8000ffff (NS_ERROR_UNEXPECTED) [nsIDOMCSSStyleDeclaration.removeProperty]"  nsresult: "0x8000ffff (NS_ERROR_UNEXPECTED)"  location: "JS frame :: chrome://inspector/content/viewers/styleRules/styleRules.js :: doTransaction :: line 560"  data: no]

Comment 1

[Robert Kaiser]

I'm seeing such weirdness here... tries to delete a chrome CSS rules from DOMI and ended up crashing in nsCOMPtr called from nsCSSRuleProcessor.

Comment 2

[Shawn Wilsher :sdwilsh]

This seems to be the case in chrome only - not content.  Not sure who to cc in layout to get their attention on this....

Comment 3

[Shawn Wilsher :sdwilsh]

Exact steps to reproduce:
1) Open DOMi
2) File->Inspect Chrome Document and select the browser window (it will have the same title as the content in the browser with a build identifier)
3) Search for "statusbar-icon" (it is the progressbar)
4) Make sure the Object - CSS Style View panel is currently being displayed, and select the first progressmeter rule.
5) Select the -moz-binding property, then press delete.

Results in previously mentioned console output.

Comment 4

[Boris Zbarsky [:bzbarsky]]

Oh, that viewer.  Yeah, it gets the rule list through internal C++ APIs that aren't exposed to script and hence don't ensure unique stylesheet inner objects, so when you try to modify a rule on a cloned sheet (as xul.css), things break, because you actually modify the rule from one clone and then ask the other clone to deal.

Note that you're not trying to remove a rule here, but a declaration; that's why I was wondering about the steps to reproduce...

See also bug 180856.  And I was pretty sure we had a more specific bug on this, but I can't find it right now.

Comment 5

[Boris Zbarsky [:bzbarsky]]

Here we are.