From: Eric S. Raymond <esr@thyrsus.com>
Date: Sun, 6 Aug 2023 11:00:22 +0000 (-0400)
Subject: Separate filename-deletion mechanism from policy.
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=10a7615b5d45bcd909bb03d67423b337dfe93b1e;p=emacs.git

Separate filename-deletion mechanism from policy.

src/fileio.c: (delete-file-internal) Renamed from delete-file,
              parallel to delete-directory-internal; policy
	      code moved to Lisp.
src/files.el: (delete-file) New function, holds policy logic.
              calls delete-file-internal.

This is a pure refactoring step, delete-file's behavior is
unchanged. But the C core is a little simpler now.
---

diff --git a/lisp/files.el b/lisp/files.el
index f8867432000..84a8c308b09 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -6352,6 +6352,26 @@ non-nil and if FN fails due to a missing file or directory."
       (apply fn args)
     (file-missing (or no-such (signal (car err) (cdr err))))))
 
+(defun delete-file (filename &optional trash)
+  "Delete file named FILENAME.  If it is a symlink, remove the symlink.
+If file has multiple names, it continues to exist with the other names.q
+TRASH non-nil means to trash the file instead of deleting, provided
+`delete-by-moving-to-trash' is non-nil.
+
+When called interactively, TRASH is t if no prefix argument is given.
+With a prefix argument, TRASH is nil."
+  (interactive (list (read-file-name
+                      (if (and delete-by-moving-to-trash (null current-prefix-arg))
+                          "Move file to trash: " "Delete file: ")
+                      nil default-directory (confirm-nonexistent-file-or-buffer))
+                     (null current-prefix-arg)))
+  (if (and (file-directory-p filename) (not (file-symlink-p filename)))
+      (signal 'file-error (list "Removing old name: is a directory" filename)))
+  (let* ((filename (expand-file-name filename)) (handler (find-file-name-handler filename 'delete-file)))
+    (cond (handler (funcall handler 'delete-file filename trash))
+          ((and delete-by-moving-to-trash trash) (move-file-to-trash filename))
+          (t (delete-file-internal filename)))))
+
 (defun delete-directory (directory &optional recursive trash)
   "Delete the directory named DIRECTORY.  Does not follow symlinks.
 If RECURSIVE is non-nil, delete files in DIRECTORY as well, with
diff --git a/src/fileio.c b/src/fileio.c
index 63f4e698528..e49a4a3836b 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -2462,38 +2462,13 @@ DEFUN ("delete-directory-internal", Fdelete_directory_internal,
   return Qnil;
 }
 
-DEFUN ("delete-file", Fdelete_file, Sdelete_file, 1, 2,
-       "(list (read-file-name \
-                (if (and delete-by-moving-to-trash (null current-prefix-arg)) \
-                    \"Move file to trash: \" \"Delete file: \") \
-                nil default-directory (confirm-nonexistent-file-or-buffer)) \
-              (null current-prefix-arg))",
+DEFUN ("delete-file-internal", Fdelete_file_internal, Sdelete_file_internal, 1, 1, 0,
        doc: /* Delete file named FILENAME.  If it is a symlink, remove the symlink.
-If file has multiple names, it continues to exist with the other names.
-TRASH non-nil means to trash the file instead of deleting, provided
-`delete-by-moving-to-trash' is non-nil.
-
-When called interactively, TRASH is t if no prefix argument is given.
-With a prefix argument, TRASH is nil.  */)
-  (Lisp_Object filename, Lisp_Object trash)
+If file has multiple names, it continues to exist with the other names. */)
+  (Lisp_Object filename)
 {
-  Lisp_Object handler;
   Lisp_Object encoded_file;
 
-  if (!NILP (Ffile_directory_p (filename))
-      && NILP (Ffile_symlink_p (filename)))
-    xsignal2 (Qfile_error,
-	      build_string ("Removing old name: is a directory"),
-	      filename);
-  filename = Fexpand_file_name (filename, Qnil);
-
-  handler = Ffind_file_name_handler (filename, Qdelete_file);
-  if (!NILP (handler))
-    return call3 (handler, Qdelete_file, filename, trash);
-
-  if (delete_by_moving_to_trash && !NILP (trash))
-    return call1 (Qmove_file_to_trash, filename);
-
   encoded_file = ENCODE_FILE (filename);
 
   if (unlink (SSDATA (encoded_file)) != 0 && errno != ENOENT)
@@ -2725,7 +2700,7 @@ This is what happens in interactive use with M-x.  */)
   if (dirp)
     call2 (Qdelete_directory, file, Qt);
   else
-    Fdelete_file (file, Qnil);
+    call2 (Qdelete_file, file, Qnil);
   return unbind_to (count, Qnil);
 }
 
@@ -6346,7 +6321,7 @@ syms_of_fileio (void)
   DEFSYM (Qcopy_file, "copy-file");
   DEFSYM (Qmake_directory_internal, "make-directory-internal");
   DEFSYM (Qmake_directory, "make-directory");
-  DEFSYM (Qdelete_file, "delete-file");
+  DEFSYM (Qdelete_file_internal, "delete-file-internal");
   DEFSYM (Qfile_name_case_insensitive_p, "file-name-case-insensitive-p");
   DEFSYM (Qrename_file, "rename-file");
   DEFSYM (Qadd_name_to_file, "add-name-to-file");
@@ -6610,6 +6585,9 @@ This includes interactive calls to `delete-file' and
   delete_by_moving_to_trash = 0;
   DEFSYM (Qdelete_by_moving_to_trash, "delete-by-moving-to-trash");
 
+  /* Lisp function for interactive file delete with trashing */
+  DEFSYM (Qdelete_file, "delete-file");
+
   /* Lisp function for moving files to trash.  */
   DEFSYM (Qmove_file_to_trash, "move-file-to-trash");
 
@@ -6641,7 +6619,7 @@ This includes interactive calls to `delete-file' and
   defsubr (&Scopy_file);
   defsubr (&Smake_directory_internal);
   defsubr (&Sdelete_directory_internal);
-  defsubr (&Sdelete_file);
+  defsubr (&Sdelete_file_internal);
   defsubr (&Sfile_name_case_insensitive_p);
   defsubr (&Srename_file);
   defsubr (&Sadd_name_to_file);