508334 - LTR text in RTL textarea may reverse while deleting text

Status: RESOLVED FIXED

(Core :: Layout: Text and Fonts, defect)

Description

[Tomer Cohen :tomer]

Attachment: testcase

When mixing between LTR and RTL text in a multiple lines textarea, while removing characters the English text can lose its direction and appear reversed in the textbox.

Steps to reproduce (see attached testcase): 
a. Place the text cursor between the two 'a' characters.
b. Press the backspace key until the English text reverse.
c. Press the backspace key again to get the English text to appear correctly again.

Issue is reproducible for me on Firefox 3.5/Gecko 1.9.1, but not on Firefox 3.0/Gecko 1.9.0.

Comment 1

[Tomer Cohen :tomer]

Attachment: screenshot of the testcase

Comment 2

[Simon Montagu :smontagu]

Attachment: more reproducable testcase

Specifying the width of the textarea makes this reproducable for me on both Mac and Linux

Comment 3

[Simon Montagu :smontagu]

Uh, no. The second testcase only shows the bug on Mac (at least with my fonts)

Comment 4

[Simon Montagu :smontagu]

As it happened I pulled today after bug 504524 was checked in and before it was backed out, and it seems to fix this.

Comment 5

[Simon Montagu :smontagu]

Fixed by bug 504524. We need to find a variation on the theme of the attached testcases which will reliably fail without the fix.

Comment 6

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Mmmm, do we want to take bug 504524 on branch? I'm not sure.

Comment 7

[Simon Montagu :smontagu]

(In reply to comment #6)
> Mmmm, do we want to take bug 504524 on branch? I'm not sure.

Is that a criterion for whether this is a blocker, or just an obiter dictum? We can probably fix this independently of bug 504524 if necessary.

Comment 8

[Robert O'Callahan (:roc) (email my personal email if necessary)]

How hard is it to fix independently?

Comment 9

[Simon Montagu :smontagu]

Because of the serendipity described in comment 4 I never investigated it thoroughly. I would guess that if I invested enough debugging time to answer the question, the actual fix would take much less time. Probably not more than one or two days' work altogether.

Comment 10

[Simon Montagu :smontagu]

Humph, it looks like this is WFM on 1.9.2, though not on 1.9.1. Possibly bug 490559 is enough to fix it.

Comment 11

[Simon Montagu :smontagu]

Yes, bug 490559 does fix this.

Comment 12

[Daniel Veditz [:dveditz]]

Sounds ugly but not really a "blocker". Happily you have already identified the patch so we'll get to that approval request.

Comment 13

[Al Billings [:abillings - ex-MoCo]]

Verified for 1.9.1 with bug 490559.