620691 - Select's value and selectedIndex is changes when selecting (not after) values

Status: RESOLVED WORKSFORME

(Core :: Layout: Form Controls, defect)

Description

[Adam Brunner]

User-Agent:       Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.2.13) Gecko/20101203 Firefox/3.6.13
Build Identifier: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.2.13) Gecko/20101203 Firefox/3.6.13

If you read a value of a select when the user is choosing between the options and moving the focus (mouse or keyboard) from one to another option, the select's value and selectedIndex will not be the original value and selectedIndex, but the currently active option's value and selectedIndex.

Reproducible: Always

Steps to Reproduce:
1. Open the page
2. Activate the select and move the mouse between the options

Actual Results:  
The selected value and selectedIndex will change to that option's value and selectedIndex you're hovering.

Expected Results:  
The value and the selectedIndex remains the original until selecting one option (until change event).

Also tried with latest Firefox 4.0 Beta 9 pre (Mozilla/5.0 (Macintosh; Intel Mac OS X 10.5; rv:2.0b9pre) Gecko/20101221 Firefox/4.0b9pre), and it still exists in it.

Comment 1

[:Ms2ger (he/him; ⌚ UTC+1/+2)]

cc'ing usual suspect.

Comment 2

[Mounir Lamouri (:mounir)]

I saw that behavior when I've implemented :-moz-ui-invalid and :-moz-ui-valid. It's really weird but that's not a regression (3.6 has the exact same behavior).

I guess this is because of nsListControlFrame::MouseMove but I don't know why we have this behavior. Boris, by any chance, do you know?

FWIW, IE6 and Opera 11 only update the selection on click. I didn't test Webkit (Safari/Chrome) and latest IE.

Comment 3

[Boris Zbarsky [:bzbarsky]]

Yeah, I think this is because of the frame stuff needing the change notifications to update what it's showing.  And yeah, we should fix this.  I bet mats knows existing bugs on this.

Comment 4

[Richard Wiseman]

It has been a long time since the status of this bug was updated.  I have today experienced the same problem using Firefox 13.0.1.  It's a pretty major problem for me because I'm checking the selection when an AJAX call returns, so it's entirely possible that the user could have the list open and be moving the mouse over it, thus confusing the interpretation of the AJAX response.

Comment 8

[Adam Brunner]

To wrap up, this bug still exists. Was able to reproduce with "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:32.0) Gecko/20100101 Firefox/32.0"

Comment 9

[BugBot [:suhaib / :marco/ :calixte]]

The severity field for this bug is relatively low, S3. However, the bug has 3 duplicates.
:emilio, could you consider increasing the bug severity?

For more information, please visit auto_nag documentation.

Comment 10

[Emilio Cobos Álvarez (:emilio)]

Page is down, reporter is inactive, and looking at dupes we no longer fire changes until the dropdown is closed.