Re: dired-details[+].el

[Stefan Monnier]

>> I discovered dired-details and dired-details+ and found them useful.
>> Could they be added to emacs?
>> http://www.emacswiki.org/emacs/DiredDetails
> They were supposed to be added.  Rob Giardina submitted an Emacs 23 patch two
> years ago that integrates the functionality of both in a better way even than
> the separate libraries dired-details[+].el.

Thanks.

> I don't think any reason was ever given for why the patch wasn't
> incorporated (committed).

A technical reason is lack of copyright paperwork.  I'm not sure if the
email I used in the Cc is valid.  If so, Rob, could you contact me to
get this copyright business out of the way?

> Rob's change log and RMS's call for comment:
> http://lists.gnu.org/archive/html/emacs-devel/2007-07/msg01187.html

This was mangled by the non-MIME forwarding, but I think I managed to
unmangle it (see after my sig).  Some of the hunks don't apply any more,
but they're trivial to fix.  There are a few minor details to make
before we can install the code:

>         * dired.el: new functions to support hiding file details in dired.

Please capitalize all the phrases in your changelog.

>         (dired-revert): delete cached overlay lists

And please punctuate them properly.

>         (dired-details): new customize group
>         New customizable vars.
>         (dired-details-hidden-string)
>         (dired-details-hide-link-targets)
>         (dired-details-initially-hide)
>         New buffer local vars.

There's some ":" missing somewhere.

> --- old/lisp/dired-x.el      Sun Jul 15 21:25:37 2007
> +++ new/lisp/dired-x.el    Sun Jul 15 22:00:23 2007
> @@ -755,7 +755,8 @@
>    (set (make-local-variable 'dired-subdir-alist) nil)
>    (dired-build-subdir-alist)
>    (goto-char (point-min))
> -  (dired-initial-position dirname))
> +  (dired-initial-position dirname)
> +  (run-hooks 'dired-after-readin-hook))

I'm not sure if this is appropriate.  But I think it's OK to just try it
and fix it later if someone reports a problem.

> +    (dired-details-delete-overlays) ;;ditch the entire overlay cache

Please capitalize and punctuate your comments.

> +    (define-key map "(" 'dired-details-hide)
> +    (define-key map ")" 'dired-details-show)
> +    (define-key map ";" 'dired-details-toggle)

I'd rather place the bindings on a "dired-details" prefix.

> +(defcustom dired-details-hidden-string "[...]"
> +  "*This string will be shown in place of file details and symbolic links."
> +  :group 'dired-details
> +  :type 'string)

No need for "*" in defcustoms.

> +(defcustom dired-details-hide-link-targets t
> +  "*Hide symbolic link target paths."
> +  :group 'dired-details
> +  :type 'boolean)

FWIW I find something like (setq truncate-lines t) to be better.
Since line truncation is the default in tabulated-list-mode, maybe we
should also make it the default in dired.

> +(defvar dired-details-state nil
> +  "Three possible values: nil (has not been set), 'hidden (details are
> +hidden), 'shown (details are visible).")
> +(make-variable-buffer-local 'dired-details-state)

The first line of a docstring should stand on its own.

> +(add-hook 'dired-after-readin-hook 'dired-details-activate)

Rather than unconditionally adding to dired-after-readin-hook, I think
we should add/remove from this hook when toggling.

> +    (dolist (overlay (cdr dir-and-overlays))
> +      (delete-overlay overlay)))

Aka (mapc #'delete-overlay (cdr dir-and-overlays)).

> +(defun dired-details-toggle (&optional arg default-too)
> +  "Toggle visibility of dired details.
> +With positive prefix argument ARG hide the details, with negative
> +show them."
> +  (interactive "P")
> +  (let ((hide (if (null arg)
> +                  (not (eq 'hidden dired-details-state))
> +                (> (prefix-numeric-value arg) 0))))
> +    (if default-too
> +        (setq dired-details-initially-hide hide))
> +    (if hide (dired-details-hide)
> +      (dired-details-show))))

Use define-minor-mode.

> +(defun dired-details-hide()

Add a space before open parentheses.

> +  "Make an invisible, evaporable overlay for each visible file
> +details in this dired buffer. This is called from

Again, the first line of a docstring should stand on its own.

> +  (unless (memq major-mode '(dired-mode vc-dired-mode))

Use derived-mode-p.

> +    (error "dired-details-hide can only be called in dired mode"))

Actually, why bother signaling an error here?

> +                 (cached-overlays
> +                  (assoc dir dired-details-internal-overlay-cache)))

BTW, why do we bother with this business of caching overlays?

> +(defun dired-details-hide-overlay (o)
> +  (overlay-put o 'invisible t)
> +  (overlay-put o 'before-string dired-details-hidden-string))

Why use dired-details-hidden-string rather than just using the
traditional ellipsis with buffer-invisibility-spec?


        Stefan


2007-07-15  Rob Giardina  <address@hidden>

        * dired.el: new functions to support hiding file details in dired.
        (dired-revert): delete cached overlay lists
        (dired-details): new customize group
        New customizable vars.
        (dired-details-hidden-string)
        (dired-details-hide-link-targets)
        (dired-details-initially-hide)
        New buffer local vars.
        (dired-details-internal-overlay-cache)
        (dired-details-state)
        New functions.
        (dired-details-activate)
        (dired-details-delete-overlays)
        (dired-details-toggle)
        (dired-details-hide)
        (dired-details-show)
        (dired-details-make-current-line-overlay)
        (dired-details-hide-overlay)
        (dired-details-show-overlay)
        (dired-details-frob-overlays)

        * dired-x.el (dired-virtual): run `dired-after-readin-hook' after
        restoring a saved dired buffer

--- old/lisp/dired-x.el      Sun Jul 15 21:25:37 2007
+++ new/lisp/dired-x.el    Sun Jul 15 22:00:23 2007
@@ -755,7 +755,8 @@
   (set (make-local-variable 'dired-subdir-alist) nil)
   (dired-build-subdir-alist)
   (goto-char (point-min))
-  (dired-initial-position dirname))
+  (dired-initial-position dirname)
+  (run-hooks 'dired-after-readin-hook))
 
 (defun dired-virtual-guess-dir ()
   "Guess and return appropriate working directory of this buffer.

--- old/lisp/dired.el   Sun Jul 15 15:42:33 2007
+++ new/lisp/dired.el   Sun Jul 15 21:19:44 2007
@@ -1042,6 +1042,7 @@
     (goto-char (point-min))
     (setq mark-alist;; only after dired-remember-hidden since this unhides:
          (dired-remember-marks (point-min) (point-max)))
+    (dired-details-delete-overlays) ;;ditch the entire overlay cache
     ;; treat top level dir extra (it may contain wildcards)
     (dired-uncache
      (if (consp dired-directory) (car dired-directory) dired-directory))
@@ -1242,6 +1243,9 @@
     (define-key map "\C-n" 'dired-next-line)
     (define-key map "\C-p" 'dired-previous-line)
     (define-key map [down] 'dired-next-line)
+    (define-key map "(" 'dired-details-hide)
+    (define-key map ")" 'dired-details-show)
+    (define-key map ";" 'dired-details-toggle)
     (define-key map [up] 'dired-previous-line)
     ;; hiding
     (define-key map "$" 'dired-hide-subdir)
@@ -3334,6 +3338,171 @@
             '(dired-mode . dired-restore-desktop-buffer))
 
 
+;;; optionally hide file details and link targets
+
+(defgroup dired-details nil
+  "Settings for to hide file details and symbolic link targets."
+  :group 'dired
+  :prefix "dired-details-")
+
+(defcustom dired-details-hidden-string "[...]"
+  "*This string will be shown in place of file details and symbolic links."
+  :group 'dired-details
+  :type 'string)
+
+(defcustom dired-details-hide-link-targets t
+  "*Hide symbolic link target paths."
+  :group 'dired-details
+  :type 'boolean)
+
+(defcustom dired-details-initially-hide nil
+  "*Hide dired details on entry to dired buffers."
+  :group 'dired-details
+  :type 'boolean)
+
+(defvar dired-details-internal-overlay-cache nil)
+(make-variable-buffer-local 'dired-details-internal-overlay-cache)
+
+(defvar dired-details-state nil
+  "Three possible values: nil (has not been set), 'hidden (details are
+hidden), 'shown (details are visible).")
+(make-variable-buffer-local 'dired-details-state)
+
+(defun dired-details-activate()
+  "Set up dired-details in the current dired buffer. Called by
+dired-after-readin-hook on initial display and when a dired
+buffer is modified. If the state of detail display has been set
+in this buffer then use that state, otherwise use the value of
+`dired-details-initially-hide'."
+  (if (eq 'hidden dired-details-state)
+      (dired-details-hide)
+      (when dired-details-initially-hide
+        (dired-details-hide))))
+(add-hook 'dired-after-readin-hook 'dired-details-activate)
+
+(defun dired-details-delete-overlays()
+  (dolist (dir-and-overlays dired-details-internal-overlay-cache)
+    (dolist (overlay (cdr dir-and-overlays))
+      (delete-overlay overlay)))
+  (setq dired-details-internal-overlay-cache nil))
+
+(defun dired-details-toggle (&optional arg default-too)
+  "Toggle visibility of dired details.
+With positive prefix argument ARG hide the details, with negative
+show them."
+  (interactive "P")
+  (let ((hide (if (null arg)
+                  (not (eq 'hidden dired-details-state))
+                (> (prefix-numeric-value arg) 0))))
+    (if default-too
+        (setq dired-details-initially-hide hide))
+    (if hide (dired-details-hide)
+      (dired-details-show))))
+
+(defun dired-details-hide()
+  "Make an invisible, evaporable overlay for each visible file
+details in this dired buffer. This is called from
+dired-after-readin-hook in different contexts: (1) narrowed to a
+single file (after copy, move, symlink etc.)  (2) narrowed to a
+single subdir (e.g. after dired-insert-subdir) (3) with multiple
+visible subdirs and not narrowed (e.g. after dired-revert)"
+  (interactive)
+  (unless (memq major-mode '(dired-mode vc-dired-mode))
+    (error "dired-details-hide can only be called in dired mode"))
+
+  (save-excursion
+    (goto-char (point-min))
+    (if (not (looking-at dired-subdir-regexp))
+        ;;a single file or files -- just make an overlay for each
+        (let* ((parent (dired-current-directory))
+               (cached-parent-overlays
+                (assoc parent dired-details-internal-overlay-cache)))
+          (unless cached-parent-overlays
+            (error "dired-details overlays not found for directory %s" parent))
+          (dired-goto-next-file)
+          (while (< (point) (point-max))
+            (dired-details-make-current-line-overlay cached-parent-overlays)
+            (dired-next-line 1)))
+
+        ;;hide each visible subdirectory (either of cases (2) or (3)
+        ;;mentioned above)
+        (dolist (dir-and-pos dired-subdir-alist)
+          (let* ((dir (car dir-and-pos))
+                 (pos (cdr dir-and-pos))
+                 (cached-overlays
+                  (assoc dir dired-details-internal-overlay-cache)))
+            ;;skip this directory if it's outside of a narrowed region
+            (when (and (>= pos (point-min)) (<= pos (point-max)))
+              (if cached-overlays
+                  (dired-details-frob-overlays t) ;;reuse existing
+                  (let ((cache (list dir)) ;;make new overlays
+                        (subdir-start (let ((rest pos))
+                                        ;;xemacs compat: in xemacs, this is a 
list
+                                        (if (atom rest) rest (car rest))))
+                        (subdir-end (1- (dired-get-subdir-max dir-and-pos))))
+                    (goto-char subdir-start)
+                    (dired-goto-next-file)
+                    (while (< (point) subdir-end)
+                      ;;nb: uses setcdr to update cache
+                      (dired-details-make-current-line-overlay cache)
+                      (dired-next-line 1))
+                    (setq dired-details-internal-overlay-cache
+                          (cons cache 
dired-details-internal-overlay-cache)))))))
+        (setq dired-details-state 'hidden))))
+
+(defun dired-details-show()
+  "Show whatever details a call to `dired-details-hide' may have
+hidden in this buffer."
+  (interactive)
+  (dired-details-frob-overlays nil)
+  (setq dired-details-state 'shown))
+
+(defun dired-details-make-current-line-overlay (cache)
+  (let ((detail-overlay ;hide the flags, size, owner, date, etc.
+         (make-overlay
+          (+ 2 (progn (beginning-of-line) (point)))
+          (progn (dired-move-to-filename)(point))))
+
+        (ln-target ;hide the destination of a symbolic when
+         (when dired-details-hide-link-targets
+           (if (progn (beginning-of-line)
+                      (search-forward-regexp
+                       "-> \\(.*\\)"
+                       (save-excursion (end-of-line)(point)) t))
+               (make-overlay (match-beginning 1) (match-end 1))))))
+
+    ;;delete the overlay when the dired line goes away
+    (overlay-put detail-overlay 'evaporate t)
+    (dired-details-hide-overlay detail-overlay)
+
+    (when ln-target
+      (overlay-put ln-target 'evaporate t)
+      (dired-details-hide-overlay ln-target))
+
+    (setcdr cache (append (if ln-target
+                              (list ln-target detail-overlay)
+                            (list detail-overlay))
+                          (cdr cache)))
+    detail-overlay))
+
+(defun dired-details-hide-overlay (o)
+  (overlay-put o 'invisible t)
+  (overlay-put o 'before-string dired-details-hidden-string))
+
+(defun dired-details-show-overlay (o)
+  (overlay-put o 'invisible nil)
+  (overlay-put o 'before-string ""))
+
+(defun dired-details-frob-overlays (hide)
+  (when dired-details-internal-overlay-cache
+    (let ((frobber (if hide 'dired-details-hide-overlay
+                            'dired-details-show-overlay)))
+      (dolist (dir-and-overlays dired-details-internal-overlay-cache)
+        (dolist (overlay (cdr dir-and-overlays))
+          (funcall frobber overlay))))))
+
+
+
 (if (eq system-type 'vax-vms)
     (load "dired-vms"))
 

--- old/doc/emacs/dired.texi      Sun Jul 15 18:00:22 2007
+++ new/doc/emacs/dired.texi    Sun Jul 15 18:00:10 2007
@@ -41,6 +41,7 @@
  @end ifnottex
  * Subdirectory Motion::             Moving across subdirectories, and up and 
down.
  * Hiding Subdirectories::     Making subdirectories visible or invisible.
+ * Hiding File Details::       Making file attributes visible or invisible.
  * Updating: Dired Updating.   Discarding lines for files of no interest.
  * Find: Dired and Find.             Using `find' to choose the files for 
Dired.
  * Wdired::                    Operating on files by editing the Dired buffer.
@@ -1011,6 +1012,45 @@
 without having to remove the Dired marks on files in those
 subdirectories.
 
address@hidden Hiding File Details
address@hidden Hiding File Details
+
address@hidden hiding in Dired (Dired)
+  @dfn{Hiding} file details means making file attributes and symbolic
+link targets invisible using overlays (@pxref{Overlays,,, elisp, the
+Emacs Lisp Reference Manual}). This converts the dired display to a
+terse list of filenames while continuing to support all normal dired
+commands.
+
address@hidden @kbd
address@hidden @kbd{;}
address@hidden dired-details-toggle
address@hidden @kbd{;} @r{(Dired)}
+Hide or reveal file details in the current Dired buffer.
+
address@hidden @kbd{(}
address@hidden dired-details-hide
address@hidden @kbd{(} @r{(Dired)}
+Hide file details in the current Dired buffer.
+
address@hidden @kbd{)}
address@hidden dired-details-hide
address@hidden @kbd{)} @r{(Dired)}
+Show file details in the current Dired buffer.
address@hidden table
+
+   You can customize @code{dired-details-hidden-string} to display any
+string in place of hidden details and link targets (the default is
+"[...]").
+
+   The option @code{dired-details-hide-link-targets} can be set to
address@hidden to show link targets when details are hidden. The default is to
+hide link targets.
+
+   Currently, the dired-sort-* family of functions do not call
address@hidden and thus will not hide details until
+the next call to @code{dired-revert} (@kbd{g}).
+
 @node Dired Updating
 @section Updating the Dired Buffer
 @cindex updating Dired buffer