bug#30503: 27.0.50; allow hiding M-x grep command line

[charles@aurox.ch (Charles A. Roelli)]

> Date: Sun, 04 Mar 2018 17:11:07 +0100
> From: charles@aurox.ch (Charles A. Roelli)
>
> > > Thanks for adding this feature.  Here's the change that implements a
> > > toggling command.
> > 
> > Thanks.  I have only one comment about the naming: since we will now have
> > grep-find-toggle-abbreviation, how about renaming for symmetry
> > grep-find-hide to e.g. grep-find-hide-abbreviation, and
> > grep-find-hide-properties to e.g. grep-find-hide-abbreviation-props?
> > 
> > Or maybe better to have the same prefix for all functions/variables
> > of this feature?
> > 
> > grep-find-abbreviation-toggle
> > grep-find-abbreviation-hide
> > grep-find-abbreviation-hide-props
> 
> I've gone for:
> 
> grep-find-abbreviate (defcustom)
> grep-find-abbreviate-properties (defvar)
> grep-find-toggle-abbreviation (command)
> 
> (Most "toggle" commands seem not to end with that word, so I've
> followed this convention.)
> 
> The patch follows:
> 
> diff --git a/doc/emacs/building.texi b/doc/emacs/building.texi
> index 0697e1b..e1c3cea 100644
> --- a/doc/emacs/building.texi
> +++ b/doc/emacs/building.texi
> @@ -434,14 +434,17 @@ Grep Searching
>  @kbd{M-x rgrep}.  The default value includes the data directories used
>  by various version control systems.
>  
> -@vindex grep-find-hide
> +@vindex grep-find-abbreviate
> +@findex grep-find-toggle-abbreviation
>    By default, the shell commands constructed for @code{lgrep},
>  @code{rgrep}, and @code{zgrep} are abbreviated for display by
>  concealing the part that contains a long list of files and directories
>  to ignore.  You can reveal the concealed part by clicking on the
> -button with ellipsis, which represents them.  To disable this
> -abbreviation of the shell commands, customize the option
> -@code{grep-find-hide} to a @code{nil} value.
> +button with ellipsis, which represents them.  You can also
> +interactively toggle viewing the concealed part by typing @kbd{M-x
> +grep-find-toggle-abbreviation}.  To disable this abbreviation of the
> +shell commands, customize the option @code{grep-find-abbreviate} to a
> +@code{nil} value.
>  
>  @node Flymake
>  @section Finding Syntax Errors On The Fly
> diff --git a/etc/NEWS b/etc/NEWS
> index 08c7e7e..24064f8 100644
> --- a/etc/NEWS
> +++ b/etc/NEWS
> @@ -209,8 +209,10 @@ by default.
>  
>  *** rgrep, lgrep and zrgrep now hide part of the command line
>  that contains a list of ignored directories and files.
> -Clicking on the button with ellipsis unhides the truncated part.
> -This truncation can be disabled by the new option 'grep-find-hide'.
> +Clicking on the button with ellipsis unhides it.
> +The abbreviation can be disabled by the new option
> +'grep-find-abbreviate'.  The new command
> +'grep-find-toggle-abbreviation' toggles it interactively.
>  
>  ** ERT
>  
> diff --git a/lisp/progmodes/grep.el b/lisp/progmodes/grep.el
> index 9b2c6f1..f7c90ba 100644
> --- a/lisp/progmodes/grep.el
> +++ b/lisp/progmodes/grep.el
> @@ -433,24 +433,26 @@ grep-mode-line-matches
>                        help-echo "Number of matches so far")
>      "]"))
>  
> -(defcustom grep-find-hide t
> +(defcustom grep-find-abbreviate t
>    "If non-nil, hide part of rgrep/lgrep/zrgrep command line.
>  The hidden part contains a list of ignored directories and files.
>  Clicking on the button-like ellipsis unhides the abbreviated part
> -and reveals the entire command line."
> +and reveals the entire command line.  The visibility of the
> +abbreviated part can also be toggled with
> +`grep-find-toggle-abbreviation'."
>    :type 'boolean
>    :version "27.1"
>    :group 'grep)
>  
> -(defvar grep-find-hide-properties
> +(defvar grep-find-abbreviate-properties
>    (let ((ellipsis (if (char-displayable-p ?…) "[…]" "[...]"))
>          (map (make-sparse-keymap)))
>      (define-key map [down-mouse-2] 'mouse-set-point)
> -    (define-key map [mouse-2] 'grep-find-show)
> -    (define-key map "\C-m" 'grep-find-show)
> +    (define-key map [mouse-2] 'grep-find-toggle-abbreviation)
> +    (define-key map "\C-m" 'grep-find-toggle-abbreviation)
>      `(face nil display ,ellipsis mouse-face highlight
>        help-echo "RET, mouse-2: show unabbreviated command"
> -      keymap ,map))
> +      keymap ,map abbreviated-command t))
>    "Properties of button-like ellipsis on part of rgrep command line.")
>  
>  (defvar grep-mode-font-lock-keywords
> @@ -476,10 +478,12 @@ grep-mode-font-lock-keywords
>               `(face nil display ,(match-string 2)))))
>       ;; Hide excessive part of rgrep command
>       ("^find \\(\\. -type d .*\\\\)\\)"
> -      (1 (when grep-find-hide grep-find-hide-properties)))
> +      (1 (if grep-find-abbreviate grep-find-abbreviate-properties
> +           '(face nil abbreviated-command t))))
>       ;; Hide excessive part of lgrep command
>       ("^grep \\( *--exclude.*--exclude[^ ]+\\)"
> -      (1 (when grep-find-hide grep-find-hide-properties))))
> +      (1 (if grep-find-abbreviate grep-find-abbreviate-properties
> +           '(face nil abbreviated-command t)))))
>     "Additional things to highlight in grep output.
>  This gets tacked on the end of the generated expressions.")
>  
> @@ -1195,23 +1199,19 @@ rgrep-default-command
>                   (shell-quote-argument ")")
>                   " -prune -o ")))))
>  
> -(defun grep-find-show ()
> -  "Show the hidden part of rgrep/lgrep/zrgrep command line."
> +(defun grep-find-toggle-abbreviation ()
> +  "Toggle showing the hidden part of rgrep/lgrep/zrgrep command line."
>    (interactive)
> -  (when (get-text-property (point) 'display)
> -    (let ((beg (or (previous-single-property-change
> -                    (min (point-max) (1+ (point))) 'display)
> -                   (point)))
> -          (end (or (next-single-property-change
> -                    (point) 'display)
> -                   (point)))
> -          (inhibit-modification-hooks t)
> -          (inhibit-read-only t)
> -	  (buffer-undo-list t)
> -	  (modified (buffer-modified-p)))
> -      (remove-list-of-text-properties
> -       beg end '(display help-echo mouse-face help-echo keymap))
> -      (set-buffer-modified-p modified))))
> +  (with-silent-modifications
> +    (let* ((beg (next-single-property-change (point-min) 'abbreviated-command))
> +           (end (when beg
> +                  (next-single-property-change beg 'abbreviated-command))))
> +      (if end
> +          (if (get-text-property beg 'display)
> +              (remove-list-of-text-properties
> +               beg end '(display help-echo mouse-face help-echo keymap))
> +            (add-text-properties beg end grep-find-abbreviate-properties))
> +        (user-error "No abbreviated part to hide/show")))))
>  
>  ;;;###autoload
>  (defun zrgrep (regexp &optional files dir confirm template)

I've pushed this change, along with a modification to add a menu-bar
item, and am closing the bug.