553280 - mails with long subjects are displayed incorrectly in the top right window ([CRLF][Tab] in Subject: header for folding is removed upon thread pane display)

Status: RESOLVED DUPLICATE of bug 593337

(Thunderbird :: Mail Window Front End, defect)

Description

[sassmann]

User-Agent:       Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.8) Gecko/20100216 Fedora/3.5.8-1.fc12 Firefox/3.5.8
Build Identifier: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.8) Gecko/20100301 Fedora/3.0.3-1.fc12 Thunderbird/3.0.3

mails with a subject longer than 80 characters sometimes get displayed incorrectly in the mail overview window (not sure how this part is called exactly, I'm talking about the part that shows all the mail subjects). A space is missing between the 2 words where the line wrapping should happen.

If the mail is being selected the subject is shown correctly in the headers section.

Recent example from [e-mail]:
subject displayed in the top window
Feature Owners: Beta Freeze is 2010-03-23 :: Features must be at100% complete
subject displayed in the tbs header section
Feature Owners: Beta Freeze is 2010-03-23 :: Features must be at 100% complete

See the difference between "at100%" and "at 100%"

Reproducible: Always

Steps to Reproduce:
1. look at [e-mail] mailing list (or other lists) and keep an eye out for posts with long subjects
2.
3.
Actual Results:  
space is missing between 2 words where line break is happening in mail subject

Expected Results:  
subject should be displayed correctly

Comment 1

[Ludovic Hirlimann [:Usul]]

Can you provide both a screenshot and a example email please ?

Comment 2

[sassmann]

Attachment: screenshot

Comment 3

[sassmann]

Attachment: mail as .eml

Comment 4

[Nathan Tuggy (:tuggyne)]

I'm sure I've seen this bug before somewhere, but can't find it off-hand. I've seen the behavior myself, though. If someone could find the dup (essentially, it's treating the tab as zero-width whitespace instead of as a line-wrap with implicit space), that'd be great.

Also, links to the relevant RFCs on header wrapping (specifically, whether to insert an extra space for a tab) would be good as well.

Comment 5

[sassmann]

RFC2822 - Internet Message Format
http://www.faqs.org/rfcs/rfc2822.html

2.2.3. Long Header Fields

   Each header field is logically a single line of characters comprising
   the field name, the colon, and the field body.  For convenience
   however, and to deal with the 998/78 character limitations per line,
   the field body portion of a header field can be split into a multiple
   line representation; this is called "folding".  The general rule is

   that wherever this standard allows for folding white space (not
   simply WSP characters), a CRLF may be inserted before any WSP.  For
   example, the header field:

           Subject: This is a test

   can be represented as:

           Subject: This
            is a test

   Note: Though structured field bodies are defined in such a way that
   folding can take place between many of the lexical tokens (and even
   within some of the lexical tokens), folding SHOULD be limited to
   placing the CRLF at higher-level syntactic breaks.  For instance, if
   a field body is defined as comma-separated values, it is recommended
   that folding occur after the comma separating the structured items in
   preference to other places where the field could be folded, even if
   it is allowed elsewhere.

   The process of moving from this folded multiple-line representation
   of a header field to its single line representation is called
   "unfolding". Unfolding is accomplished by simply removing any CRLF
   that is immediately followed by WSP.  Each header field should be
   treated in its unfolded form for further syntactic and semantic
   evaluation.

Comment 6

[sassmann]

My guess would be that thunderbird, while unfolding, removes the CRLF + first whitespace in the second line. Instead only the CRLF should be removed as the RFC suggests.

Example
Subject: This is a test

This gets folded into
Subject: This
 is a test
^--this space might be falsely removed while unfolding and the result would be

Subject: Thisis a test

Comment 7

[Nathan Tuggy (:tuggyne)]

Ah, there we go, it's bug 271312.

Comment 8

[WADA:World Anti-bad-Duping Agency]

(In reply to comment #7)
> Ah, there we go, it's bug 271312.

Nathan Tuggy, really dup of bug 271312?

AFAIR, phenomenon of bug 271312 was "htab in subject is displayed by U+FFFD because no font has Glyph for htab".
This bug is for phenomenon that "at[HTAB][CRLF]100%" part of attached test mail is displayed by Tb 3.0.3(opener) and Tb 3.0.4(me) like;
  Thread pane             : at100%    (HTAB is removed)
  Tool tip at Thread pane : at   100% (HTAB for indention. Text editor like.)
  Message header Box      : at 100%   (HTAB is rendered as space. HTML like.)
Data in .msf file is as follows.
> <(86=[e-mail])(87=21)(88
>     =John Poelstra <[e-mail]>)(89
>     =[e-mail])(8A
>     =Feature Owners: Beta Freeze is 2010-03-23 :: Features must be at$0D$0A$09\
> 100% complete)(8B=[e-mail])(8D=4ba1640a)(8E=us-ascii)

Problem of this bug is;
Thread pane display removes [CRLF][HTAB] instead of "remove [CRLF] and replace [HTAB] by a space"(this is request of bug 271312).
Bug 271312 comment #32 is not repoting original problem of Bug 271312. That comment reports phenomenon reported this bug's phenomenon in thread pane display and in printing.

Comment 9

[WADA:World Anti-bad-Duping Agency]

Duping to bug 593337 instead of Bug 271312, for ease of tracking, to avoid confusion.