bug#20847: [display engine] 25.0.50; company-mode popup makes point jump to an entirely different location

[Dmitry Gutov]

On 06/22/2015 07:23 PM, Eli Zaretskii wrote:

> I see.  Is this something you need to determine in addition to knowing
> whether point is at the last position of a screen line?

I think so. It's only when point is at the last position, and when the 
line continues afterwards, and there's no truncation, or word-wrap, that 
I could omit the newline at the beginning of the completion overlay 
display string. And I've probably missed some possibility.

That's a lot of things to check.

> The example I have is the exact recipe with which you started this bug
> report.  As soon as you type "el" in step 6, and the "tooltip" with
> completions pops up, look at the next paragraph of text below the
> "tooltip" -- you will see the rightmost character on every line of
> that paragraph disappear.  (For this to show, you need to have both
> fringes, but "emacs -Q" should make sure you do.)

Thank you. I've never noticed it myself before. It was an implementation 
quirk, now fixed in master.