Re: [PATCH] Option for updating modeline VC state.

[Stefan Monnier <monnier@iro.umontreal.ca>]

> In short, the VC state modeline is changed to signal `edited' the first
> time the file is saved. Even if subsequent editions revert the file to
> its pristine state, the VC state modeline will keep showing the `edited'
> flag. As Dan is concerned about performance issues if VC asks the
> backend for the state of the file, this is implemented as an option
> disabled by default.

Maybe there are backends where this option might be "necessary", but
until this is proved to be the case, I'd rather not have any option and
instead consider any performance problem as a bug.

One more thing, tho: I'd really like it if this state-recomputation
could be done once for all the affected nuffers (i.e. for the buffer
currently visiting the file as well as all the vc-dir buffers that
include the file).  Could someone refactor the code accordingly?


        Stefan


> 2009-09-24  Oscar Fuentes  <ofv@wanadoo.es>

> 	* lisp/vc-hooks.el (vc-always-update-modeline-after-save):
>         new defcustom.
>         (vc-after-save): Use it and when non-nil check the vc file state
>         so the modeline reflects its actual state.


> diff -cp "c:/apps/emacs/lisp/vc-hooks.el" "d:/vc-hooks.el"
> *** c:/apps/emacs/lisp/vc-hooks.el	2009-09-24 07:25:53.000000000 +0200
> --- d:/vc-hooks.el	2009-09-24 08:10:01.062500000 +0200
> *************** If nil (the default), files covered by v
> *** 96,101 ****
> --- 96,110 ----
>     :group 'vc
>     :group 'backup)
  
> + (defcustom vc-always-update-modeline-after-save nil
> +   "If non-nil, always update the state shown in the modeline
> + after saving the file. This may be time-consuming for some
> + backends. If nil, the modeline changes to `edited' when the file
> + is saved for the first time and it is not updated on subsequent
> + saves."
> +   :type 'boolean
> +   :group 'vc)
> + 
>   (defcustom vc-follow-symlinks 'ask
>     "What to do if visiting a symbolic link to a file under version control.
>   Editing such a file through the link bypasses the version control system,
> *************** Before doing that, check if there are an
> *** 743,751 ****
>   		  ;; to avoid confusion.
>   		  (vc-file-setprop file 'vc-checkout-time nil))
>   	     t)
> -          (vc-up-to-date-p file)
>            (eq (vc-checkout-model backend (list file)) 'implicit)
> !          (vc-file-setprop file 'vc-state 'edited)
>   	 (vc-mode-line file backend)
>   	 ;; Try to avoid unnecessary work, a *vc-dir* buffer is
>   	 ;; present if and only if this is true.
> --- 752,766 ----
>   		  ;; to avoid confusion.
>   		  (vc-file-setprop file 'vc-checkout-time nil))
>   	     t)
>            (eq (vc-checkout-model backend (list file)) 'implicit)
> ! 	 (if vc-always-update-modeline-after-save
> ! 	     (progn
> ! 	       ;; Avoid using cached value on `vc-state':
> ! 	       (vc-file-setprop file 'vc-state 'nil)
> ! 	       (vc-file-setprop file 'vc-state (vc-state file backend)))
> ! 	   (and
> ! 	    (vc-up-to-date-p file)
> ! 	    (vc-file-setprop file 'vc-state 'edited)))
>   	 (vc-mode-line file backend)
>   	 ;; Try to avoid unnecessary work, a *vc-dir* buffer is
>   	 ;; present if and only if this is true.