714162 - Don't traverse certainly alive selections

Status: RESOLVED FIXED

(Core :: DOM: Selection, defect)

Description

[Olli Pettay [:smaug][[e-mail]]]

Attachment: patch

nsFrameSelection is kept alive by Presshell (until Presshell is deleted) and
for text form controls nsTextEditorState/nsTextControlFrame.
When presshell is going away mShell is set to null using DisconnectFromPresShell.

So, as long a mShell is there, the nsFrameSelection object should be certainly alive and 
the whole traversing is just useless.

Comment 1

[Mats Palmgren (inactive)]

Yes, the above comment is correct.  I'm not familiar with the cycle collector or
what NS_SUCCESS_INTERRUPTED_TRAVERSE means though, so you should get someone else
to review the actual code change.

Comment 2

[Olli Pettay [:smaug][[e-mail]]]

https://tbpl.mozilla.org/?tree=Try&rev=685465da3f10

Comment 3

[Andrew McCreight [:mccr8]]

Comment on attachment 584818 [details] [diff] [review]
patch

Review of attachment 584818 [details] [diff] [review]:
-----------------------------------------------------------------

Looks good. Death to death stars!

r=me given mats's comment.

Comment 4

[Olli Pettay [:smaug][[e-mail]]]

https://hg.mozilla.org/mozilla-central/rev/0d684c34d1e4

Comment 5

[Olli Pettay [:smaug][[e-mail]]]

Attachment: Safer version

I started to worry about this a bit, so better be safe.

Comment 6

[Andrew McCreight [:mccr8]]

Comment on attachment 585860 [details] [diff] [review]
Safer version

Review of attachment 585860 [details] [diff] [review]:
-----------------------------------------------------------------

The diff on top of the previous patch wasn't really necessary for a tiny patch.

At some point, we should probably another CC macro for this pattern (if document is non-null and in the current generation, return interrupted traverse).

Comment 7

[Olli Pettay [:smaug][[e-mail]]]

https://hg.mozilla.org/mozilla-central/rev/57a33c9f08b1