Mode for editing patches?

Mode for editing patches?

[Paul Smith]

So, I used to (in a previous incarnation of my development environment)
be able to edit a patch file and do things like add or remove lines from
the patch file, and Emacs would automatically update the unified diff
header info (lines add/removed, etc.)

I don't remember installing or configuring anything special to get this
behavior, but I must have because in my current environment when I visit
patch files I get normal "Diff" mode, which has nice font-locking but no
support for inline editing of the diff (as far as I can tell).

I'm sure I didn't imagine this.  Can someone suggest what I used to use,
or what I'd configured before, that I cannot remember now?

I'm using Emacs 24.3.1 on GNU/Linux.

Re: Mode for editing patches?

[Stefan Monnier]

> I'm sure I didn't imagine this.  Can someone suggest what I used to use,
> or what I'd configured before, that I cannot remember now?

This support should be enabled by default without having to do anything.
You may have to C-x C-q to make the buffer writable, of course, but
that's about it.


        Stefan

Re: Mode for editing patches?

[Damien Wyart]

* Paul Smith <psmith@gnu.org> in gnu.emacs.help:
> So, I used to (in a previous incarnation of my development
> environment) be able to edit a patch file and do things like add or
> remove lines from the patch file, and Emacs would automatically update
> the unified diff header info (lines add/removed, etc.)

You might have diff-update-on-the-fly set to nil.

-- 
DW