Possible to hook into Emacs's buffer name generation?

Possible to hook into Emacs's buffer name generation?

[Sean McAfee]

Lately I've been doing a lot of editing inside a large source
repository.  Sometimes I'll have different versions of the same source
file open at the same time, and it's a bit of a hassle to have to keep
in mind whether the older or the newer version is the one with a "<2>"
after its name in the mode line.

I thought it might be cool to have Emacs automatically name buffers that
are visiting files in my repository with a trailing "<component-x.y.z>"
when I open them, where component-x.y.z is simply the closest directory
name above the file that matches that pattern.  I could do this by
adding a hook to find-file-hooks and renaming the buffer according to my
scheme, but it seems cleaner to tell Emacs how to generate the desired
buffer name in the first place.  I've traced the code from find-file all
the way down to generate-new-buffer-name, but I can't find anywhere I
can interpose my buffer-naming logic.

Did I miss something, or am I out of luck?

Re: Possible to hook into Emacs's buffer name generation?

[Leo]

On 2011-02-18 08:28 +0800, Sean McAfee wrote:
> Lately I've been doing a lot of editing inside a large source
> repository.  Sometimes I'll have different versions of the same source
> file open at the same time, and it's a bit of a hassle to have to keep
> in mind whether the older or the newer version is the one with a "<2>"
> after its name in the mode line.
>
> I thought it might be cool to have Emacs automatically name buffers that
> are visiting files in my repository with a trailing "<component-x.y.z>"
> when I open them, where component-x.y.z is simply the closest directory
> name above the file that matches that pattern.  I could do this by
> adding a hook to find-file-hooks and renaming the buffer according to my
> scheme, but it seems cleaner to tell Emacs how to generate the desired
> buffer name in the first place.  I've traced the code from find-file all
> the way down to generate-new-buffer-name, but I can't find anywhere I
> can interpose my buffer-naming logic.
>
> Did I miss something, or am I out of luck?

Maybe you can build on top of uniquify.el?

Leo

Re: Possible to hook into Emacs's buffer name generation?

[Óscar Fuentes]

Sean McAfee <eefacm@gmail.com> writes:

[snip]

> I thought it might be cool to have Emacs automatically name buffers that
> are visiting files in my repository with a trailing "<component-x.y.z>"
> when I open them, where component-x.y.z is simply the closest directory
> name above the file that matches that pattern.

See if this helps:

C-h v uniquify-buffer-name-style

> I could do this by
> adding a hook to find-file-hooks and renaming the buffer according to my
> scheme, but it seems cleaner to tell Emacs how to generate the desired
> buffer name in the first place.  I've traced the code from find-file all
> the way down to generate-new-buffer-name, but I can't find anywhere I
> can interpose my buffer-naming logic.

The mechanism proposed above advises `create-file-buffer':

(defadvice create-file-buffer (after create-file-buffer-uniquify activate)
  "Uniquify buffer names with parts of directory name."
...

That is in the last lines of lisp/uniquify.el

Re: Possible to hook into Emacs's buffer name generation?

[Tassilo Horn]

Leo <sdl.web@gmail.com> writes:

> Maybe you can build on top of uniquify.el?

I'm using that, which does the trick.

  (require 'uniquify)
  (setq uniquify-buffer-name-style 'post-forward-angle-brackets)

,----[ C-h v uniquify-buffer-name-style RET ]
| uniquify-buffer-name-style is a variable defined in `uniquify.el'.
| Its value is post-forward-angle-brackets
| Original value was nil
| 
| Documentation:
| If non-nil, buffer names are uniquified with parts of directory name.
| The value determines the buffer name style and is one of `forward',
| `reverse', `post-forward', or `post-forward-angle-brackets'.
| For example, files `/foo/bar/mumble/name' and `/baz/quux/mumble/name'
| would have the following buffer names in the various styles:
|   forward        bar/mumble/name  quux/mumble/name
|   reverse        name\mumble\bar  name\mumble\quux
|   post-forward   name|bar/mumble  name|quux/mumble
|   post-forward-angle-brackets   name<bar/mumble>  name<quux/mumble>
|   nil            name  name<2>
| Of course, the "mumble" part may be stripped as well, depending on the setting
| of `uniquify-strip-common-suffix'.
`----

Bye,
Tassilo

Re: Possible to hook into Emacs's buffer name generation?

[Sean McAfee]

Leo <sdl.web@gmail.com> writes:

> On 2011-02-18 08:28 +0800, Sean McAfee wrote:
>> I thought it might be cool to have Emacs automatically name buffers that
>> are visiting files in my repository with a trailing "<component-x.y.z>"
>> when I open them, where component-x.y.z is simply the closest directory
>> name above the file that matches that pattern.

> Maybe you can build on top of uniquify.el?

I hadn't known of uniquify, but after some experimentation it seems not
to offer everything I'd like.  In particular, I want a trailing
component-x.y.z on the buffer name even when I'm not already visiting
the same file in a different directory.  uniquify only steps in when
there's a name conflict.

I wrote a short find-file hook to fix the buffer name, so it's not that
big a deal.

Re: Possible to hook into Emacs's buffer name generation?

[Stefan Monnier]

> I hadn't known of uniquify, but after some experimentation it seems not
> to offer everything I'd like.  In particular, I want a trailing
> component-x.y.z on the buffer name even when I'm not already visiting
> the same file in a different directory.  uniquify only steps in when
> there's a name conflict.

Depending on your needs, uniquify-min-dir-content might do the trick.


        Stefan