Re: electric-pair-mode as a minor mode?

[Dmitry Gutov <dgutov@yandex.ru>]

On 04/13/2015 01:16 AM, joaotavora@gmail.com (João Távora) wrote:

> (I pressed `M-p', not `M-n').

Right, that.

> That's right. Although I can't resist asking why these "Summary" and
> "Author" hints/cookies can't be some display-only element like a
> before-string in an overlay. Why are they implemented as actual buffer
> text?

I guess partly because it can be handled similarly to mail buffers (and 
maybe, at some point, some code can be merged).

And while "Summary:" could be implemented as a before-string on an 
overlay (or even purely with font-lock, maybe), other headers need extra 
processing: transform the value, move it to a different part of the 
buffer, etc. Aside from "Author" and "Signed-Off-By", we can encounter 
"Fixes:" and now, after the ChangeLogs conversion, 
"Copyright-paperwork-exempt:" and "Also-By:" (or some alternative thereof).

And good luck saving/restoring overlays in M-n/M-p implementations. Text 
prop-based implementation would handle this better, but how to use them 
in this context isn't necessarily apparent to me.

> Never tried it. Didn't know they existed even. I make commits from
> vc-dir and command line alternately as is more convenient, so I
> `log-edit-mode' in COMMIT_EDITMSG for a consistent UI.

I'm guessing git-commit-mode from MELPA would probably be a better fit, 
even if it has different interface.

>> Maybe somewhere in `before-save-hook' of the new major mode?
>
> Won't kick in when the buffer doesn't need saving.

But COMMIT_EDITMSG needs to be saved, doesn't it?

> This seems works nicely though:

log-edit-callback looks like a nice option, too.

> Got it in my .emacs, but perhaps this could be installed, seems generic
> enough.

It should probably handle other headers as well. I don't know if Git 
allows to set arguments like --author or --signed-off-by via some 
special comments in the commit file, but if it did, that would allow to 
unify the implementations nicely.