bug#48125: 28.0.50; Display garbled by emoji variation sequence

[Filipp Gunbin <fgunbin@fastmail.fm>]

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On 04/05/2021 22:29 +0300, Eli Zaretskii wrote:

>> Date: Tue, 04 May 2021 22:17:18 +0300
>> From: Eli Zaretskii <eliz@gnu.org>
>> Cc: 48125@debbugs.gnu.org
>>
>> > From: Filipp Gunbin <fgunbin@fastmail.fm>
>> > Cc: 48125@debbugs.gnu.org
>> > Date: Tue, 04 May 2021 22:06:36 +0300
>> >
>> > One more question.  In the attached screenshot there're two lines, one
>> > with soccer balls (width 2), and another with letter "a" (width 1).
>> > Both do not fit on screen, and are continued to the next (screen) line.
>> > When at EOL of either, C-x = reports column=142, but the first is longer
>> > (by 1 column).  That is because it's continued with two backslashes, not
>> > one.  Is this the right behavior?
>>
>> I don't see the continuation backslashes in the screenshot, but from
>> your description the behavior sounds right.  There could even be more
>> than 2 backslashes in some rare cases.
>
> Oh, and of course the backslashes aren't counted as part of the column
> number, only the displayed text is counted.

Re-checked - they should be visible in the screenshot (maybe you didn't
scroll the image to the right?)

Ok, I have two continuation backslashes in the end of the screen line
with soccer balls.  But what I wanted to note is that on continuation
lines, I get equal column numbers at different screen positions.

I've now made two screenshots with point at each EOL, to show that
screen positions are different.


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