bug#60146: file-exists-in-trash-p needs better name or semantics

[Paul Eggert <eggert@cs.ucla.edu>]

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On 12/17/22 00:47, Eli Zaretskii wrote:
> I don't really mind renaming that function, but the reason I called it
> like I did was that apparently no one needed such a functionality in
> Emacs until now,

I have a bit of a different take. First, there's adequate functionality 
in Emacs now if we don't mind inefficiency, and it's already used; just 
call file-attributes. (Gnus does this, in nnmaildir-unlink at least, and 
I expect there are other uses.) Second, I wouldn't be surprised if other 
uses of file-exists-p have problems similar to the one you found in 
move-file-to-trash. Not that any of us have time to go scout for them 
right now.

It's a minor point. Still, the name file-exists-in-trash-p really needs 
to go somehow as it's not a name that should be user-visible. How about 
the attached patch?


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From adcf3112e72431e4c4a2610941afcc238e7dd243 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Sat, 17 Dec 2022 11:54:46 -0800
Subject: [PATCH] Remove file-exists-in-trash-p

* lisp/files.el (file-exists-in-trash-p): Remove, as this name is
not suitable for users.  All uses replaced by file-attributes,
which is good enough here.
---
 lisp/files.el | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/lisp/files.el b/lisp/files.el
index c74e7e808e4..149480a6f10 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -8467,14 +8467,6 @@ trash--hexify-table
 
 (declare-function system-move-file-to-trash "w32fns.c" (filename))
 
-(defun file-exists-in-trash-p (filename)
-  "Return non-nil if FILENAME exists in the trash.
-
-This is like `file-exists-p', but it also returns non-nil
-if FILENAME is a dangling symlink, to allow trashing such files."
-  (or (file-exists-p filename)
-      (file-symlink-p filename)))
-
 (defun move-file-to-trash (filename)
   "Move the file (or directory) named FILENAME to the trash.
 When `delete-by-moving-to-trash' is non-nil, this function is
@@ -8505,7 +8497,7 @@ move-file-to-trash
 	   (unless (file-directory-p trash-dir)
 	     (make-directory trash-dir t))
 	   ;; Ensure that the trashed file-name is unique.
-	   (if (file-exists-in-trash-p new-fn)
+	   (if (file-attributes new-fn)
 	       (let ((version-control t)
 		     (backup-directory-alist nil))
 		 (setq new-fn (car (find-backup-file-name new-fn)))))
@@ -8582,7 +8574,7 @@ move-file-to-trash
                  ;; We're checking further down whether the info file
                  ;; exists, but the file name may exist in the trash
                  ;; directory even if there is no info file for it.
-                 (when (file-exists-in-trash-p
+                 (when (file-attributes
                         (file-name-concat trash-files-dir files-base))
                    (setq overwrite t
                          files-base (file-name-nondirectory
@@ -8620,7 +8612,7 @@ move-file-to-trash
 		 (let ((delete-by-moving-to-trash nil)
 		       (new-fn (file-name-concat trash-files-dir files-base)))
                    (if (or (not is-directory)
-                           (not (file-exists-in-trash-p new-fn)))
+                           (not (file-attributes new-fn)))
                        (rename-file fn new-fn overwrite)
                      (copy-directory fn
                                      (file-name-as-directory new-fn)
-- 
2.38.1