bug#18475: 24.4.50; Wdired: cannot use C-k to delete a dir name if -F switch used

bug#18475: 24.4.50; Wdired: cannot use C-k to delete a dir name if -F switch used

[Drew Adams]

The `wdired-mode' doc string says: "If you delete the filename of a
file, it is flagged for deletion in the Dired buffer."  And (emacs)
`Wdired' says: "To mark a file for deletion, delete the entire file
name."

And this applies to directory names also.

No problem, except if you use `ls' switch `-F', which appends `/' to
directory names.  In that case, if you try to use `C-k' anywhere on the
dir name text, you get the error "Text is read only".

(Yes, you can use other deletion keys besides `C-k' to delete the dir
name but not delete the `/'.  That looks weird and is not easily
guessable by users, but it works.  `C-k' should work also, as one would
expect.)

In GNU Emacs 24.4.50.1 (i686-pc-mingw32)
 of 2014-08-15 on LEG570
Bzr revision: 117706 rgm@gnu.org-20140815043406-p5hbu97cbm7pulcn
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --enable-checking 'CFLAGS=-O0 -g3' CPPFLAGS=-DGLYPH_DEBUG=1'

bug#18475: 24.4.50; Wdired: cannot use C-k to delete a dir name if -F switch used

[Basil L. Contovounesios]

Drew Adams <drew.adams@oracle.com> writes:

> The `wdired-mode' doc string says: "If you delete the filename of a
> file, it is flagged for deletion in the Dired buffer."  And (emacs)
> `Wdired' says: "To mark a file for deletion, delete the entire file
> name."
>
> And this applies to directory names also.
>
> No problem, except if you use `ls' switch `-F', which appends `/' to
> directory names.  In that case, if you try to use `C-k' anywhere on the
> dir name text, you get the error "Text is read only".
>
> (Yes, you can use other deletion keys besides `C-k' to delete the dir
> name but not delete the `/'.  That looks weird and is not easily
> guessable by users, but it works.  `C-k' should work also, as one would
> expect.)
>
> In GNU Emacs 24.4.50.1 (i686-pc-mingw32)
>  of 2014-08-15 on LEG570
> Bzr revision: 117706 rgm@gnu.org-20140815043406-p5hbu97cbm7pulcn
> Windowing system distributor `Microsoft Corp.', version 6.1.7601
> Configured using:
>  `configure --enable-checking 'CFLAGS=-O0 -g3' CPPFLAGS=-DGLYPH_DEBUG=1'

I can still reproduce this on Emacs 26 and latest master.

Stephen, any chance you could take a look at this given your recent work
in the area?

Thanks,

-- 
Basil

bug#18475: 24.4.50; Wdired: cannot use C-k to delete a dir name if -F switch used

[Stephen Berman]

On Sat, 27 Apr 2019 01:09:16 +0100 "Basil L. Contovounesios" <contovob@tcd.ie> wrote:

> Drew Adams <drew.adams@oracle.com> writes:
>
>> The `wdired-mode' doc string says: "If you delete the filename of a
>> file, it is flagged for deletion in the Dired buffer."  And (emacs)
>> `Wdired' says: "To mark a file for deletion, delete the entire file
>> name."
>>
>> And this applies to directory names also.
>>
>> No problem, except if you use `ls' switch `-F', which appends `/' to
>> directory names.  In that case, if you try to use `C-k' anywhere on the
>> dir name text, you get the error "Text is read only".
>>
>> (Yes, you can use other deletion keys besides `C-k' to delete the dir
>> name but not delete the `/'.  That looks weird and is not easily
>> guessable by users, but it works.  `C-k' should work also, as one would
>> expect.)
>>
>> In GNU Emacs 24.4.50.1 (i686-pc-mingw32)
>>  of 2014-08-15 on LEG570
>> Bzr revision: 117706 rgm@gnu.org-20140815043406-p5hbu97cbm7pulcn
>> Windowing system distributor `Microsoft Corp.', version 6.1.7601
>> Configured using:
>>  `configure --enable-checking 'CFLAGS=-O0 -g3' CPPFLAGS=-DGLYPH_DEBUG=1'
>
> I can still reproduce this on Emacs 26 and latest master.
>
> Stephen, any chance you could take a look at this given your recent work
> in the area?

Thanks for bringing this to my attention.  I've started looking at it
and have an idea I'll try to work out.

Steve Berman

bug#18475: 24.4.50; Wdired: cannot use C-k to delete a dir name if -F switch used

[Basil L. Contovounesios]

Stephen Berman <stephen.berman@gmx.net> writes:

> On Sat, 27 Apr 2019 01:09:16 +0100 "Basil L. Contovounesios" <contovob@tcd.ie> wrote:
>
>> Stephen, any chance you could take a look at this given your recent work
>> in the area?
>
> Thanks for bringing this to my attention.  I've started looking at it
> and have an idea I'll try to work out.

Thanks!

-- 
Basil

bug#18475: 24.4.50; Wdired: cannot use C-k to delete a dir name if -F switch used

[Stephen Berman]

[-- Attachment #1: Type: text/plain, Size: 3158 bytes --]

On Sat, 27 Apr 2019 01:09:16 +0100 "Basil L. Contovounesios" <contovob@tcd.ie> wrote:

> Drew Adams <drew.adams@oracle.com> writes:
>
>> The `wdired-mode' doc string says: "If you delete the filename of a
>> file, it is flagged for deletion in the Dired buffer."  And (emacs)
>> `Wdired' says: "To mark a file for deletion, delete the entire file
>> name."
>>
>> And this applies to directory names also.
>>
>> No problem, except if you use `ls' switch `-F', which appends `/' to
>> directory names.  In that case, if you try to use `C-k' anywhere on the
>> dir name text, you get the error "Text is read only".
>>
>> (Yes, you can use other deletion keys besides `C-k' to delete the dir
>> name but not delete the `/'.  That looks weird and is not easily
>> guessable by users, but it works.  `C-k' should work also, as one would
>> expect.)
>>
>> In GNU Emacs 24.4.50.1 (i686-pc-mingw32)
>>  of 2014-08-15 on LEG570
>> Bzr revision: 117706 rgm@gnu.org-20140815043406-p5hbu97cbm7pulcn
>> Windowing system distributor `Microsoft Corp.', version 6.1.7601
>> Configured using:
>>  `configure --enable-checking 'CFLAGS=-O0 -g3' CPPFLAGS=-DGLYPH_DEBUG=1'
>
> I can still reproduce this on Emacs 26 and latest master.

This happens not only with `/' but also with the other ls file indicator
characters appended when using the -F switch.  Making C-k work as
expected for these cases is a small fix.  However, the same issue also
arises with symlinks, whether or not -F is used, and it does not seem as
straightforward to deal with this case.  The attached patch (against
master) tries to ensure the following behavior:

- Typing `C-k' with point just before the first character of a file name
  ending with an indicator character (using -F), or of link name,
  deletes the file name/symlink in WDired, but it is restored but marked
  for deletion on returning to Dired.  The same also happens when just
  deleting the link name in WDired.

- Typing `C-k' with point on such a file or link name, but after the
  first character, deletes the rest, resulting in renaming on returning
  to Dired.

- Deleting the indicator character is possible in WDired but a noop: the
  character is restored on returning to Dired.  (In the current code
  without the patch, the indicator characters are read-only, but I had
  to change that to make C-k work.)

With symlinks:

- The patch preserves the current behavior that an edit of the target
  name (possible when wdired-allow-to-redirect-links is non-nil, as it
  is by default) is saved on returning to Dired, and if the target name
  is deleted, then the new target on returning to Dired is "/dev/null".

- Editing (changing or deleting) the string " -> " between the link and
  target names is possible in WDired but a noop: the symlink is
  unaltered on returning to Dired.  (In the current code without the
  patch, " -> " is read-only, but I had to change that to make C-k work.)

I've tested these cases, but it is quite possible that I overlooked some
variants or other cases, so I'd appreciate testing and feedback from
others.  (Also, the code still needs more commenting and probably
cleaning up.)

Steve Berman


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: wdired patch --]
[-- Type: text/x-patch, Size: 9118 bytes --]

diff --git a/lisp/wdired.el b/lisp/wdired.el
index d2a298bd25..e44b619b46 100644
--- a/lisp/wdired.el
+++ b/lisp/wdired.el
@@ -255,7 +255,7 @@ wdired-change-to-wdired-mode
   (setq buffer-read-only nil)
   (dired-unadvertise default-directory)
   (add-hook 'kill-buffer-hook 'wdired-check-kill-buffer nil t)
-  (add-hook 'after-change-functions 'wdired--restore-dired-filename-prop nil t)
+  (add-hook 'after-change-functions 'wdired--restore-properties nil t)
   (setq major-mode 'wdired-mode)
   (setq mode-name "Editable Dired")
   (setq revert-buffer-function 'wdired-revert)
@@ -266,7 +266,7 @@ wdired-change-to-wdired-mode
   (wdired-preprocess-files)
   (if wdired-allow-to-change-permissions
       (wdired-preprocess-perms))
-  (if (and wdired-allow-to-redirect-links (fboundp 'make-symbolic-link))
+  (if (fboundp 'make-symbolic-link)
       (wdired-preprocess-symlinks))
   (buffer-enable-undo) ; Performance hack. See above.
   (set-buffer-modified-p nil)
@@ -288,6 +288,7 @@ wdired-preprocess-files
   (save-excursion
     (goto-char (point-min))
     (let ((b-protection (point))
+          (used-F (dired-check-switches dired-actual-switches "F" "classify"))
 	  filename)
       (while (not (eobp))
 	(setq filename (dired-get-filename nil t))
@@ -299,8 +300,16 @@ wdired-preprocess-files
 	  (add-text-properties
 	   (1- (point)) (point) `(old-name ,filename rear-nonsticky (read-only)))
 	  (put-text-property b-protection (point) 'read-only t)
-	  (setq b-protection (dired-move-to-end-of-filename t))
+          (dired-move-to-end-of-filename t)
 	  (put-text-property (point) (1+ (point)) 'end-name t))
+          (when (and used-F (looking-at "[*/@|=>]$")) (forward-char))
+          (when (save-excursion
+                  (and (re-search-backward
+                        dired-permission-flags-regexp nil t)
+                       (looking-at "l")
+                       (search-forward " -> " (line-end-position) t)))
+            (goto-char (line-end-position)))
+	  (setq b-protection (point))
         (forward-line))
       (put-text-property b-protection (point-max) 'read-only t))))

@@ -327,7 +336,8 @@ wdired-get-filename
 non-nil means don't include directory.  Optional arg OLD with value
 non-nil means return old filename."
   ;; FIXME: Use dired-get-filename's new properties.
-  (let (beg end file)
+  (let ((used-F (dired-check-switches dired-actual-switches "F" "classify"))
+        beg end file)
     (save-excursion
       (setq end (line-end-position))
       (beginning-of-line)
@@ -339,7 +349,20 @@ wdired-get-filename
 	  ;; the filename end is found even when the filename is empty.
 	  ;; Fixes error and spurious newlines when marking files for
 	  ;; deletion.
-	  (setq end (next-single-property-change beg 'end-name))
+	  (setq end (next-single-property-change beg 'end-name nil end))
+          (when (save-excursion
+                  (and (re-search-forward
+                        dired-permission-flags-regexp nil t)
+                       (goto-char (match-beginning 0))
+                       (looking-at "l")
+                       (search-forward " -> " (line-end-position) t)))
+            (goto-char (match-beginning 0))
+            (setq end (point)))
+          (when (and used-F
+                     (save-excursion
+                       (goto-char end)
+                       (looking-back "[*/@|=>]$" (1- (point)))))
+              (setq end (1- end)))
 	  (setq file (buffer-substring-no-properties (1+ beg) end)))
 	;; Don't unquote the old name, it wasn't quoted in the first place
         (and file (setq file (wdired-normalize-filename file (not old)))))
@@ -364,7 +387,7 @@ wdired-change-to-dired-mode
   (setq mode-name "Dired")
   (dired-advertise)
   (remove-hook 'kill-buffer-hook 'wdired-check-kill-buffer t)
-  (remove-hook 'after-change-functions 'wdired--restore-dired-filename-prop t)
+  (remove-hook 'after-change-functions 'wdired--restore-properties t)
   (set (make-local-variable 'revert-buffer-function) 'dired-revert))


@@ -425,9 +448,9 @@ wdired-finish-edit
     (when files-renamed
       (setq errors (+ errors (wdired-do-renames files-renamed))))
     ;; We have to be in wdired-mode when wdired-do-renames is executed
-    ;; so that wdired--restore-dired-filename-prop runs, but we have
-    ;; to change back to dired-mode before reverting the buffer to
-    ;; avoid using wdired-revert, which changes back to wdired-mode.
+    ;; so that wdired--restore-properties runs, but we have to change
+    ;; back to dired-mode before reverting the buffer to avoid using
+    ;; wdired-revert, which changes back to wdired-mode.
     (wdired-change-to-dired-mode)
     (if changes
 	(progn
@@ -449,7 +472,11 @@ wdired-finish-edit
 				'(old-name nil end-name nil old-link nil
 					   end-link nil end-perm nil
 					   old-perm nil perm-changed nil))
-	(message "(No changes to be performed)")))
+	(message "(No changes to be performed)")
+        ;; Deleting file indicator characters or editing the symlink
+        ;; arrow in WDired are noops, so redisplay them immediately on
+        ;; returning to Dired.
+        (revert-buffer)))
     (when files-deleted
       (wdired-flag-for-deletion files-deleted))
     (when (> errors 0)
@@ -603,11 +630,21 @@ wdired-check-kill-buffer
 ;; dired-filename text property, which allows functions that look for
 ;; this property (e.g. dired-isearch-filenames) to work in wdired-mode
 ;; and also avoids an error with non-nil wdired-use-interactive-rename
-;; (bug#32173).
-(defun wdired--restore-dired-filename-prop (beg end _len)
+;; (bug#32173).  Also prevents editing the symlink arrow (which is a
+;; noop) from corrupting the link name (see bug#18475 for elaboration).
+(defun wdired--restore-properties (beg end _len)
   (save-match-data
     (save-excursion
       (let ((lep (line-end-position)))
+        ;; Deleting the space between the link name and the arrow (a
+        ;; noop) also deletes the end-name property, so restore it.
+        (when (and (save-excursion
+                     (re-search-backward dired-permission-flags-regexp nil t)
+                     (looking-at "l"))
+                   (get-text-property (1- (point)) 'dired-filename)
+                   (not (get-text-property (point) 'dired-filename))
+                   (not (get-text-property (point) 'end-name)))
+            (put-text-property (point) (1+ (point)) 'end-name t))
         (beginning-of-line)
         (when (re-search-forward
                directory-listing-before-filename-regexp lep t)
@@ -665,34 +702,37 @@ wdired-preprocess-symlinks
     (save-excursion
       (goto-char (point-min))
       (while (not (eobp))
-        (if (looking-at dired-re-sym)
-            (progn
-              (re-search-forward " -> \\(.*\\)$")
-	      (put-text-property (- (match-beginning 1) 2)
-				 (1- (match-beginning 1)) 'old-link
-				 (match-string-no-properties 1))
-              (put-text-property (match-end 1) (1+ (match-end 1)) 'end-link t)
-              (put-text-property (1- (match-beginning 1))
-				 (match-beginning 1)
-				 'rear-nonsticky '(read-only))
-	      (put-text-property (match-beginning 1)
-				 (match-end 1) 'read-only nil)))
+        (when (looking-at dired-re-sym)
+          (re-search-forward " -> \\(.*\\)$")
+	  (put-text-property (1- (match-beginning 1))
+			     (match-beginning 1) 'old-link
+			     (match-string-no-properties 1))
+          (put-text-property (match-end 1) (1+ (match-end 1)) 'end-link t)
+          (unless wdired-allow-to-redirect-links
+            (put-text-property (match-beginning 0)
+			       (match-end 1) 'read-only t)))
         (forward-line)
 	(beginning-of-line)))))

-
 (defun wdired-get-previous-link (&optional old move)
   "Return the next symlink target.
 If OLD, return the old target.  If MOVE, move point before it."
   (let (beg end target)
     (setq beg (previous-single-property-change (point) 'old-link nil))
-    (if beg
-	(progn
-	  (if old
-	      (setq target (get-text-property (1- beg) 'old-link))
-	    (setq end (next-single-property-change beg 'end-link))
-	    (setq target (buffer-substring-no-properties (1+ beg) end)))
-	  (if move (goto-char (1- beg)))))
+    (when beg
+      (when (save-excursion
+              (goto-char beg)
+              (and (looking-at " ")
+                   (looking-back " ->" (line-beginning-position))))
+        (setq beg (1+ beg)))
+      (if old
+          (setq target (get-text-property (1- beg) 'old-link))
+        (setq end (save-excursion
+                    (goto-char beg)
+                    (next-single-property-change beg 'end-link nil
+                                                 (line-end-position))))
+        (setq target (buffer-substring-no-properties beg end)))
+	  (if move (goto-char (1- beg))))
     (and target (wdired-normalize-filename target t))))

 (declare-function make-symbolic-link "fileio.c")

bug#18475: 24.4.50; Wdired: cannot use C-k to delete a dir name if -F switch used

[Basil L. Contovounesios]

Stephen Berman <stephen.berman@gmx.net> writes:

> This happens not only with `/' but also with the other ls file indicator
> characters appended when using the -F switch.  Making C-k work as
> expected for these cases is a small fix.  However, the same issue also
> arises with symlinks, whether or not -F is used, and it does not seem as
> straightforward to deal with this case.  The attached patch (against
> master) tries to ensure the following behavior:
>
> - Typing `C-k' with point just before the first character of a file name
>   ending with an indicator character (using -F), or of link name,
>   deletes the file name/symlink in WDired, but it is restored but marked
>   for deletion on returning to Dired.  The same also happens when just
>   deleting the link name in WDired.
>
> - Typing `C-k' with point on such a file or link name, but after the
>   first character, deletes the rest, resulting in renaming on returning
>   to Dired.
>
> - Deleting the indicator character is possible in WDired but a noop: the
>   character is restored on returning to Dired.  (In the current code
>   without the patch, the indicator characters are read-only, but I had
>   to change that to make C-k work.)
>
> With symlinks:
>
> - The patch preserves the current behavior that an edit of the target
>   name (possible when wdired-allow-to-redirect-links is non-nil, as it
>   is by default) is saved on returning to Dired, and if the target name
>   is deleted, then the new target on returning to Dired is "/dev/null".
>
> - Editing (changing or deleting) the string " -> " between the link and
>   target names is possible in WDired but a noop: the symlink is
>   unaltered on returning to Dired.  (In the current code without the
>   patch, " -> " is read-only, but I had to change that to make C-k work.)
>
> I've tested these cases, but it is quite possible that I overlooked some
> variants or other cases, so I'd appreciate testing and feedback from
> others.  (Also, the code still needs more commenting and probably
> cleaning up.)

I can confirm your patch fixes the issue in the OP, but I haven't tested
it extensively.

Thanks for working on this,

-- 
Basil

bug#18475: 24.4.50; Wdired: cannot use C-k to delete a dir name if -F switch used

[Lars Ingebrigtsen]

"Basil L. Contovounesios" <contovob@tcd.ie> writes:

>> I've tested these cases, but it is quite possible that I overlooked some
>> variants or other cases, so I'd appreciate testing and feedback from
>> others.  (Also, the code still needs more commenting and probably
>> cleaning up.)
>
> I can confirm your patch fixes the issue in the OP, but I haven't tested
> it extensively.

The patch no longer applies to Emacs 28, so I've respun the patch
(included below).

I've given it some light testing, and it seems to fix the problem for
me, but there's been other changes in this area in the meantime...
Could people who use wdired a lot give this patch a spin and see whether
it works for them?

diff --git a/lisp/wdired.el b/lisp/wdired.el
index b98becfafe..2c2d3cec25 100644
--- a/lisp/wdired.el
+++ b/lisp/wdired.el
@@ -255,7 +255,7 @@ wdired-change-to-wdired-mode
   (setq buffer-read-only nil)
   (dired-unadvertise default-directory)
   (add-hook 'kill-buffer-hook 'wdired-check-kill-buffer nil t)
-  (add-hook 'after-change-functions 'wdired--restore-dired-filename-prop nil t)
+  (add-hook 'after-change-functions 'wdired--restore-properties nil t)
   (setq major-mode 'wdired-mode)
   (setq mode-name "Editable Dired")
   (setq revert-buffer-function 'wdired-revert)
@@ -266,7 +266,7 @@ wdired-change-to-wdired-mode
   (wdired-preprocess-files)
   (if wdired-allow-to-change-permissions
       (wdired-preprocess-perms))
-  (if (and wdired-allow-to-redirect-links (fboundp 'make-symbolic-link))
+  (if (fboundp 'make-symbolic-link)
       (wdired-preprocess-symlinks))
   (buffer-enable-undo) ; Performance hack. See above.
   (set-buffer-modified-p nil)
@@ -288,6 +288,7 @@ wdired-preprocess-files
   (save-excursion
     (goto-char (point-min))
     (let ((b-protection (point))
+          (used-F (dired-check-switches dired-actual-switches "F" "classify"))
 	  filename)
       (while (not (eobp))
 	(setq filename (dired-get-filename nil t))
@@ -299,8 +300,16 @@ wdired-preprocess-files
 	  (add-text-properties
 	   (1- (point)) (point) `(old-name ,filename rear-nonsticky (read-only)))
 	  (put-text-property b-protection (point) 'read-only t)
-	  (setq b-protection (dired-move-to-end-of-filename t))
+          (dired-move-to-end-of-filename t)
 	  (put-text-property (point) (1+ (point)) 'end-name t))
+          (when (and used-F (looking-at "[*/@|=>]$")) (forward-char))
+          (when (save-excursion
+                  (and (re-search-backward
+                        dired-permission-flags-regexp nil t)
+                       (looking-at "l")
+                       (search-forward " -> " (line-end-position) t)))
+            (goto-char (line-end-position)))
+	  (setq b-protection (point))
         (forward-line))
       (put-text-property b-protection (point-max) 'read-only t))))
 
@@ -327,7 +336,8 @@ wdired-get-filename
 non-nil means don't include directory.  Optional arg OLD with value
 non-nil means return old filename."
   ;; FIXME: Use dired-get-filename's new properties.
-  (let (beg end file)
+  (let ((used-F (dired-check-switches dired-actual-switches "F" "classify"))
+        beg end file)
     (save-excursion
       (setq end (line-end-position))
       (beginning-of-line)
@@ -339,7 +349,20 @@ wdired-get-filename
 	  ;; the filename end is found even when the filename is empty.
 	  ;; Fixes error and spurious newlines when marking files for
 	  ;; deletion.
-	  (setq end (next-single-property-change beg 'end-name))
+	  (setq end (next-single-property-change beg 'end-name nil end))
+          (when (save-excursion
+                  (and (re-search-forward
+                        dired-permission-flags-regexp nil t)
+                       (goto-char (match-beginning 0))
+                       (looking-at "l")
+                       (search-forward " -> " (line-end-position) t)))
+            (goto-char (match-beginning 0))
+            (setq end (point)))
+          (when (and used-F
+                     (save-excursion
+                       (goto-char end)
+                       (looking-back "[*/@|=>]$" (1- (point)))))
+              (setq end (1- end)))
 	  (setq file (buffer-substring-no-properties (1+ beg) end)))
 	;; Don't unquote the old name, it wasn't quoted in the first place
         (and file (setq file (wdired-normalize-filename file (not old)))))
@@ -366,7 +389,7 @@ wdired-change-to-dired-mode
   (setq mode-name "Dired")
   (dired-advertise)
   (remove-hook 'kill-buffer-hook 'wdired-check-kill-buffer t)
-  (remove-hook 'after-change-functions 'wdired--restore-dired-filename-prop t)
+  (remove-hook 'after-change-functions 'wdired--restore-properties t)
   (set (make-local-variable 'revert-buffer-function) 'dired-revert))
 
 
@@ -427,9 +450,9 @@ wdired-finish-edit
     (when files-renamed
       (setq errors (+ errors (wdired-do-renames files-renamed))))
     ;; We have to be in wdired-mode when wdired-do-renames is executed
-    ;; so that wdired--restore-dired-filename-prop runs, but we have
-    ;; to change back to dired-mode before reverting the buffer to
-    ;; avoid using wdired-revert, which changes back to wdired-mode.
+    ;; so that wdired--restore-properties runs, but we have to change
+    ;; back to dired-mode before reverting the buffer to avoid using
+    ;; wdired-revert, which changes back to wdired-mode.
     (wdired-change-to-dired-mode)
     (if changes
 	(progn
@@ -451,7 +474,11 @@ wdired-finish-edit
 				'(old-name nil end-name nil old-link nil
 					   end-link nil end-perm nil
 					   old-perm nil perm-changed nil))
-	(message "(No changes to be performed)")))
+	(message "(No changes to be performed)")
+        ;; Deleting file indicator characters or editing the symlink
+        ;; arrow in WDired are noops, so redisplay them immediately on
+        ;; returning to Dired.
+        (revert-buffer)))
     (when files-deleted
       (wdired-flag-for-deletion files-deleted))
     (when (> errors 0)
@@ -605,14 +632,24 @@ wdired-check-kill-buffer
 ;; dired-filename text property, which allows functions that look for
 ;; this property (e.g. dired-isearch-filenames) to work in wdired-mode
 ;; and also avoids an error with non-nil wdired-use-interactive-rename
-;; (bug#32173).
-(defun wdired--restore-dired-filename-prop (beg end _len)
+;; (bug#32173).  Also prevents editing the symlink arrow (which is a
+;; noop) from corrupting the link name (see bug#18475 for elaboration).
+(defun wdired--restore-properties (beg end _len)
   (save-match-data
     (save-excursion
       (let ((lep (line-end-position))
             (used-F (dired-check-switches
                      dired-actual-switches
                      "F" "classify")))
+        ;; Deleting the space between the link name and the arrow (a
+        ;; noop) also deletes the end-name property, so restore it.
+        (when (and (save-excursion
+                     (re-search-backward dired-permission-flags-regexp nil t)
+                     (looking-at "l"))
+                   (get-text-property (1- (point)) 'dired-filename)
+                   (not (get-text-property (point) 'dired-filename))
+                   (not (get-text-property (point) 'end-name)))
+            (put-text-property (point) (1+ (point)) 'end-name t))
         (beginning-of-line)
         (when (re-search-forward
                directory-listing-before-filename-regexp lep t)
@@ -676,33 +713,36 @@ wdired-preprocess-symlinks
     (save-excursion
       (goto-char (point-min))
       (while (not (eobp))
-        (if (looking-at dired-re-sym)
-            (progn
-              (re-search-forward " -> \\(.*\\)$")
-	      (put-text-property (- (match-beginning 1) 2)
-				 (1- (match-beginning 1)) 'old-link
-				 (match-string-no-properties 1))
-              (put-text-property (match-end 1) (1+ (match-end 1)) 'end-link t)
-              (put-text-property (1- (match-beginning 1))
-				 (match-beginning 1)
-				 'rear-nonsticky '(read-only))
-	      (put-text-property (match-beginning 1)
-				 (match-end 1) 'read-only nil)))
+        (when (looking-at dired-re-sym)
+          (re-search-forward " -> \\(.*\\)$")
+	  (put-text-property (1- (match-beginning 1))
+			     (match-beginning 1) 'old-link
+			     (match-string-no-properties 1))
+          (put-text-property (match-end 1) (1+ (match-end 1)) 'end-link t)
+          (unless wdired-allow-to-redirect-links
+            (put-text-property (match-beginning 0)
+			       (match-end 1) 'read-only t)))
         (forward-line)))))
 
-
 (defun wdired-get-previous-link (&optional old move)
   "Return the next symlink target.
 If OLD, return the old target.  If MOVE, move point before it."
   (let (beg end target)
     (setq beg (previous-single-property-change (point) 'old-link nil))
-    (if beg
-	(progn
-	  (if old
-	      (setq target (get-text-property (1- beg) 'old-link))
-	    (setq end (next-single-property-change beg 'end-link))
-	    (setq target (buffer-substring-no-properties (1+ beg) end)))
-	  (if move (goto-char (1- beg)))))
+    (when beg
+      (when (save-excursion
+              (goto-char beg)
+              (and (looking-at " ")
+                   (looking-back " ->" (line-beginning-position))))
+        (setq beg (1+ beg)))
+      (if old
+          (setq target (get-text-property (1- beg) 'old-link))
+        (setq end (save-excursion
+                    (goto-char beg)
+                    (next-single-property-change beg 'end-link nil
+                                                 (line-end-position))))
+        (setq target (buffer-substring-no-properties beg end)))
+      (if move (goto-char (1- beg))))
     (and target (wdired-normalize-filename target t))))
 
 (declare-function make-symbolic-link "fileio.c")


-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#18475: 24.4.50; Wdired: cannot use C-k to delete a dir name if -F switch used

[Stephen Berman]

On Tue, 25 Aug 2020 12:11:22 +0200 Lars Ingebrigtsen <larsi@gnus.org> wrote:

> "Basil L. Contovounesios" <contovob@tcd.ie> writes:
>
>>> I've tested these cases, but it is quite possible that I overlooked some
>>> variants or other cases, so I'd appreciate testing and feedback from
>>> others.  (Also, the code still needs more commenting and probably
>>> cleaning up.)
>>
>> I can confirm your patch fixes the issue in the OP, but I haven't tested
>> it extensively.
>
> The patch no longer applies to Emacs 28, so I've respun the patch
> (included below).

Thanks.

> I've given it some light testing, and it seems to fix the problem for
> me, but there's been other changes in this area in the meantime...
> Could people who use wdired a lot give this patch a spin and see whether
> it works for them?

In particular, there were changes to fix problems with using the -F
switch on macOS, right?  So it would be good for people who use that
system (I don't) to test the patch.

Steve Berman

bug#18475: 24.4.50; Wdired: cannot use C-k to delete a dir name if -F switch used

[Lars Ingebrigtsen]

Stephen Berman <stephen.berman@gmx.net> writes:

> In particular, there were changes to fix problems with using the -F
> switch on macOS, right?  So it would be good for people who use that
> system (I don't) to test the patch.

Nobody piped up, so I've pushed the patch to the trunk, although we'll
have to be prepared to revert it if it turns out to be problematic on
Macos.  I'll try to do some testing myself...

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no