bug#23871: 25.1.50; Undo unexpectedly leads to blank buffer

[phillip.lord@russet.org.uk (Phillip Lord)]

Markus Triska <triska@metalevel.at> writes:

> Hi Phillip,
>
> phillip.lord@russet.org.uk (Phillip Lord) writes:
>
>> I believe the following patch addresses the issue.
>
> This patch causes a regression with the original case I posted in this
> report (#23871):
>
> Without your patch, after undo, point is *either*
>
> (1) at the beginning of line 15 OR
> (2) at a position that is outside the buffer (point 323 of 322).
>
> Case (1) is the expected behaviour, and case (2) is the issue I reported
> and which, just FYI, also still arises with your patch applied.
>
> However, your patch also leads to the new problem that even in cases
> where the point is not outside the buffer, it is unexpectedly placed at
> the *end* of line 15 instead of at the beginning, where ediprolog-dwim
> was invoked before the insertion is undone.
>
> In this sense, the behaviour is worse than before for #23871 with your
> patch, because point is never restored to where the interaction started.


I haven't started to look at 23871 yet, only 21722; I would rather deal
with the simple case first. Can you tell me whether it fixes this case?

Phil