722639 - Needs some automated tests for bug 692145

Status: RESOLVED FIXED

(Core :: DOM: UI Events & Focus Handling, defect)

Description

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

I have no idea to test the actual cause of bug 692145 directly.

However, I think that we can test something related of the bug:

1. Add NS_ABORT_IF_FALSE() into the CountNewlinesIn*().
2. Insert a lot of lines in <textarea>
3. Do query the text rect of each line's start.

Then, between the each line's y should be same distance (might be different 1px by subpixel positioning though).

Comment 1

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Attachment: Patch

Comment 2

[(no longer active)]

Comment on attachment 593319 [details] [diff] [review]
Patch

Review of attachment 593319 [details] [diff] [review]:
-----------------------------------------------------------------

The 1px tolerance is fragile.  Can't you just store the last item's .top+.height, and verify that the .top of the next element is greater than that value?

Comment 3

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

(In reply to Ehsan Akhgari [:ehsan] from comment #2)
> The 1px tolerance is fragile.  Can't you just store the last item's
> .top+.height, and verify that the .top of the next element is greater than
> that value?

Hmm, no, it isn't. On Linux, lines may be overlapped each other. Actually, lines overlap each other 2px on tryserver. It's valid for CSS and not a problem for composition.

Comment 4

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Comment on attachment 593319 [details] [diff] [review]
Patch

requesting r again for my previous comment.

Comment 5

[(no longer active)]

Comment on attachment 593319 [details] [diff] [review]
Patch

OK, fair enough!

Comment 6

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/08b3c9d38e32

Comment 7

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/08b3c9d38e32