77394 - incorrect handling of empty text nodes (like word break)

Status: VERIFIED FIXED

(Core :: Layout, defect)

Description

[Kathleen :Brade]

I will attach a testcase which I developed after finding a bug when editing
plain text.  This testcase shows that the bug isn't in the editor but rather in
the wordbreak or linebreak code when encountering empty text nodes.

To reproduce:
  load the attachment/test case
  enter some text with no spaces in the 3rd editfield (such as "1234567890")
  press add a few times
  remove the text in the 3rd editfield
  press add a few more times (insertion of empty text nodes)
  enter some text with no spaces in the 3rd editfield (such as "abcdefghijkl")
  press add a few times until you see a line break between the first set of text
and the second set of text

expectation:  an empty text node should not cause the line to break

Comment 1

[Kathleen :Brade]

Attachment: file to help reproduce bug (see steps in bug)

Comment 2

[Frank Tang]

erik resign. reassign all his bug to ftang for now.

Comment 3

[Frank Tang]

shanjian- line break issue. Please help to take care

Comment 4

[Shanjian Li]

I do not see any problem here. In your reproduce step, you input "123456789" in 3rd edit field, and 
then add empty text node, and then "abcdefg". Because "123456789" and "abcdefg"  are of different 
category, line/word break might happen. If you just use "aaaa" and "bbbb" and such, you will see 
that it works fine. 
Reopen if my understanding is incorrect. 

Comment 5

[Kathleen :Brade]

reopen bug until we've clarified...

Shanjian--can you explain what you mean by "are of different category"?  This can 
be reproduced by using the same string ("abcdefghijklmnopqrst") with empty text 
nodes.  The text added doesn't really matter, the problem seems to be with the 
empty text nodes.

Comment 6

[Frank Tang]

brade- how important is this one? is it moz0.9.2 or future?

Comment 7

[kinmoz]

Without a fix, people might see wierd wrapping while deleting lines in 
textareas. Several people have already reported this problem.

This bug was filed just to prove that the problem exists outside of the editor 
context.

Wrapping content that contained empty text nodes used to work, so something 
regressed it.

Comment 8

[Shanjian Li]

Ok, I reproduced the problem and found out that this is a layout issue. 
patch will follow soon.

Comment 9

[Shanjian Li]

Attachment: proposed fix, correct handling empty text node in lookahead text-run measurement

Comment 10

[Shanjian Li]

set milstone to 0.9.3. We might want to change it to 0.9.2. 

Comment 11

[Chris Waterson]

Nice! r=waterson

Comment 12

[Shanjian Li]

chris, since you are a super-reviewer, can you give sr as well?

Comment 13

[Shanjian Li]

add [e-mail] to cc list

Marc, can you sr this one?

Comment 14

[Marc Attinasi]

sr=attinasi

Comment 15

[Shanjian Li]

fix checked in to trunk.

Comment 16

[Chris Petersen]

Marking verified fixed in the Sept 5th build (2001-09-05-05)