Empathy aligns RTL text as LTR text on messenger

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install empathy on Hebrew Ubuntu add account with windows users which is basically the only users i have and i guess normal msn and try to write things in Hebrew and see if they align to the left or to the right i tested it so far with two users and both told me that when i use empathy it's align to the left and with pidgin it's align properly to the right that is all i can tell you.

msn account i don't know about other protocols for now.

Back to new, as aviramof provided the steps to reproduce the bug.
It would be great if someone else with a RTL language installed can confirm the bug.

This bug sound like an upstream bug and I'll take a "wild" guess and say the fix is probably the same one I did in Pidgin a few years ago:
http://shlomil.blogspot.com/2007/02/patch-to-fix-some-bidi-text-issues-in.html

RL=1 should be passed for RTL messages in MSN protocol.
Wireshark can be used to confirm what flag value is used by Empathy.

Solution: The first letter of the message should be detected for direction and set the flag accordingly (AKA, the Gnome way).

confirmed.
also, the hebrew messages are locally aligned to the left on the chat window, not only on the remote side's window, but that's for another bug :)

Thanks a lot for confirming. I have reported this bug upstream to GNOME and it can be tracked at https://bugzilla.gnome.org/show_bug.cgi?id=630632. This should import bug comments, but its a new feature so it's best to follow at the bugzilla site in case anything is needed.

This was bounced from project to project and ended up in telepathy-spec at <https://bugs.freedesktop.org/show_bug.cgi?id=30396>.

However, I'm not sure whether this is actually relevant to telepathy-spec, because I don't think the communication between Empathy and its MSN backend should need to specify the text direction if it can be detected automatically.

Is it meant to be possible to auto-detect alignment from the text of the message? It seems to be, since if I copy "שרה" from http://en.wikipedia.org/wiki/Bi-directional_text and send it between my XMPP accounts, the edit box displays it right-aligned (however, the conversation history displays it left-aligned).

So, I think there are really three bugs here, of which we can't fix (B):

(A) For all protocols, Empathy should auto-detect whether the text should be RTL, and if so, right-align the text in the conversation history

(B) (not fixable by us!) MSN on Windows should auto-detect whether the text should be RTL in the same way as (A), rather than relying on the RL=1 flag

(C) To work around (B), telepathy-butterfly (which Empathy uses for MSN) should auto-detect whether the text should be RTL, and if so, set the RL=1 flag when it sends it to the MSN server

People who speak RTL languages: does that sound like a reasonable course of action?

An alternative course of action would be to give Telepathy messages a flag similar to MSN's RL=1, which indicates "the main context's writing direction" (as described in <http://en.wikipedia.org/wiki/Bi-directional_text>).

Since I don't know how RTL languages work, I can't judge whether auto-detection is enough or whether we need a flag. I'd prefer to use auto-detection if we can, though.

<Frustration>
Well, Going by the GNOME logic (which I dislike .. sigh ( https://bugzilla.gnome.org/show_bug.cgi?id=167354 ))
.. the auto-detection should be just fine (option C).

The grandmothers using Gnome should be smart enough to insert the Invisible Unicode LRM/RLM characters when auto-detection goes wrong (which happens very rarely I must admit ).
</Frustration>

I'm afraid the problem get even more complex since last time I checked, MSN didn't support RLM/LRM so well (this might have been changed by now) and in this case butterfly should remove the RLM/LRM marks and set MSN's RL flag accordingly.

IMO, Support for Rich text solves the problem since you may specify both alignment and direction (note these are actually two different properties) for different parts of the text and let the protocol plugin do what it can to send it correctly.

Maybe Behdad Esfahbod should be asked for his opinion on this.

Dear ones,

How does Windows MSN client determine whether to use the RL=1 flag? Does anyone know? Can anyone guess?

Blessings,
Shahar

@Shahar
I do not know what Windows MSN is using but Pidgin is open-source and is successful at sending this flag. I'm no developer but it seems to me this could be figured out from the pidgin/libpurple source code.