bug#62029: 29.0.60; Allow users to customize eldoc buffer separator

[Dmitry Gutov <dmitry@gutov.dev>]

On 18/04/2023 14:17, João Távora wrote:
> On Tue, Apr 18, 2023 at 1:47 AM Dmitry Gutov <dmitry@gutov.dev> wrote:
> 
>> Here is a minor suggestion:
>>
> 
>> The negative width stops the line height from shifting, and the increase
>> in font size is definitely subjective, but 0.7 really looked too small here.
> 
> Feel free to push that, it makes sense.  But maybe halfway at 0.8?

Split that in half again and pushed 0.85 ;-) Feel free to revert or 
change, of course.

> More seriously though, this clashes with Company's overlay-based
> dropdown, and I don't know how to fix that.> Company makes Flymake's
> end-of-line overlay temporarily invisible, which is good, but
> it still takes a lot of space, so the dropdown is ridiculously
> offset to the right.

Right. Like line numbers or other display-related features.

I'm not sure how to fix that for the overlay popup frontend, but one 
good news is that people can use child frame based ones, those should be 
compatible.

For all other users (like tty ones), also consider a different mode of 
operation: when the corresponding overlay is only shown when point is on 
the error, or mouse hovers over it. That can reduce the odds of conflict 
to the minimum.

This was it would be a straight substitute for help-at-pt and eldoc, for 
flymake's purposes.