Some Tramp fixes for directory-files-* and delete-*

* lisp/files.el (delete-directory): Simplify check for trash.

* lisp/net/ange-ftp.el (ange-ftp-delete-file): Implement TRASH.

* lisp/net/tramp-compat.el (tramp-compat-directory-files)
(tramp-compat-directory-files-and-attributes)
(tramp-compat-directory-empty-p): New defaliases.

* lisp/net/tramp.el (tramp-handle-directory-files-and-attributes)
(tramp-skeleton-delete-directory):
* lisp/net/tramp-gvfs.el (tramp-gvfs-handle-delete-directory): Use them.

* lisp/net/tramp-sh.el (tramp-sh-handle-directory-files-and-attributes):
Implement COUNT.

* test/lisp/net/tramp-tests.el (tramp-test14-delete-directory):
Do not run trash test for ange-ftp.
(tramp-test16-directory-files)
(tramp-test19-directory-files-and-attributes): Check COUNT argument.

lisp/files.el

@@ -5867,10 +5867,7 @@ RECURSIVE if DIRECTORY is nonempty."
       ;; case, where the operation fails in delete-directory-internal.
       ;; As `move-file-to-trash' trashes directories (empty or
       ;; otherwise) as a unit, we do not need to recurse here.
-      (if (and (not recursive)
-	       ;; Check if directory is empty apart from "." and "..".
-	       (directory-files
-		directory 'full directory-files-no-dot-files-regexp))
+      (if (not (or recursive (directory-empty-p directory)))
 	  (error "Directory is not empty, not moving to trash")
 	(move-file-to-trash directory)))
      ;; Otherwise, call ourselves recursively if needed.

lisp/net/ange-ftp.el

@@ -3536,20 +3536,22 @@ system TYPE.")
   (setq file (expand-file-name file))
   (let ((parsed (ange-ftp-ftp-name file)))
     (if parsed
-	(let* ((host (nth 0 parsed))
-	       (user (nth 1 parsed))
-	       (name (ange-ftp-quote-string (nth 2 parsed)))
-	       (abbr (ange-ftp-abbreviate-filename file))
-	       (result (ange-ftp-send-cmd host user
-					  (list 'delete name)
-					  (format "Deleting %s" abbr))))
-	  (or (car result)
-	      (signal 'ftp-error
-		      (list
-		       "Removing old name"
-		       (format "FTP Error: \"%s\"" (cdr result))
-		       file)))
-	  (ange-ftp-delete-file-entry file))
+        (if (and delete-by-moving-to-trash trash)
+	    (move-file-to-trash file)
+	  (let* ((host (nth 0 parsed))
+	         (user (nth 1 parsed))
+	         (name (ange-ftp-quote-string (nth 2 parsed)))
+	         (abbr (ange-ftp-abbreviate-filename file))
+	         (result (ange-ftp-send-cmd host user
+					    (list 'delete name)
+					    (format "Deleting %s" abbr))))
+	    (or (car result)
+	        (signal 'ftp-error
+		        (list
+		         "Removing old name"
+		         (format "FTP Error: \"%s\"" (cdr result))
+		         file)))
+	    (ange-ftp-delete-file-entry file)))
       (ange-ftp-real-delete-file file trash))))
 
 (defun ange-ftp-file-modtime (file)
@@ -4163,45 +4165,55 @@ directory, so that Emacs will know its current contents."
 
 (defun ange-ftp-delete-directory (dir &optional recursive trash)
   (if (file-directory-p dir)
-      (let ((parsed (ange-ftp-ftp-name dir)))
-	(if recursive
-	    (mapc
-	     (lambda (file)
-	       (if (file-directory-p file)
-		   (ange-ftp-delete-directory file recursive trash)
-		 (delete-file file trash)))
-	     (directory-files dir 'full directory-files-no-dot-files-regexp)))
-	(if parsed
-	    (let* ((host (nth 0 parsed))
-		   (user (nth 1 parsed))
-		   ;; Some ftp's on unix machines (at least on Suns)
-		   ;; insist that rmdir take a filename, and not a
-		   ;; directory-name name as an arg. Argh!! This is a bug.
-		   ;; Non-unix machines will probably always insist
-		   ;; that rmdir takes a directory-name as an arg
-		   ;; (as the ftp man page says it should).
-		   (name (ange-ftp-quote-string
-			  (if (eq (ange-ftp-host-type host) 'unix)
-			      (ange-ftp-real-directory-file-name
-			       (nth 2 parsed))
-			    (ange-ftp-real-file-name-as-directory
-			     (nth 2 parsed)))))
-		   (abbr (ange-ftp-abbreviate-filename dir))
-		   (result
-		    (progn
-		      ;; CWD must not in this directory.
-		      (ange-ftp-cd host user "/" 'noerror)
-		      (ange-ftp-send-cmd host user
-					 (list 'rmdir name)
-					 (format "Removing directory %s"
-						 abbr)))))
-	      (or (car result)
-		  (ange-ftp-error host user
-				  (format "Could not remove directory %s: %s"
-					  dir
-					  (cdr result))))
-	      (ange-ftp-delete-file-entry dir t))
-	  (ange-ftp-real-delete-directory dir recursive trash)))
+      ;; Trashing directories does not work yet, because
+      ;; `rename-file', called in `move-file-to-trash', does not
+      ;; handle directories.
+      (if nil ; (and delete-by-moving-to-trash trash)
+	  ;; Move non-empty dir to trash only if recursive deletion was
+	  ;; requested.
+	  (if (not (or recursive (directory-empty-p dir)))
+	      (signal 'ftp-error
+                      (list "Directory is not empty, not moving to trash"))
+	    (move-file-to-trash dir))
+        (let ((parsed (ange-ftp-ftp-name dir)))
+	  (if recursive
+	      (mapc
+	       (lambda (file)
+	         (if (file-directory-p file)
+		     (ange-ftp-delete-directory file recursive)
+		   (delete-file file)))
+	       (directory-files dir 'full directory-files-no-dot-files-regexp)))
+	  (if parsed
+	      (let* ((host (nth 0 parsed))
+		     (user (nth 1 parsed))
+		     ;; Some ftp's on unix machines (at least on Suns)
+		     ;; insist that rmdir take a filename, and not a
+		     ;; directory-name name as an arg. Argh!! This is a bug.
+		     ;; Non-unix machines will probably always insist
+		     ;; that rmdir takes a directory-name as an arg
+		     ;; (as the ftp man page says it should).
+		     (name (ange-ftp-quote-string
+			    (if (eq (ange-ftp-host-type host) 'unix)
+			        (ange-ftp-real-directory-file-name
+			         (nth 2 parsed))
+			      (ange-ftp-real-file-name-as-directory
+			       (nth 2 parsed)))))
+		     (abbr (ange-ftp-abbreviate-filename dir))
+		     (result
+		      (progn
+		        ;; CWD must not in this directory.
+		        (ange-ftp-cd host user "/" 'noerror)
+		        (ange-ftp-send-cmd host user
+					   (list 'rmdir name)
+					   (format "Removing directory %s"
+						   abbr)))))
+	        (or (car result)
+		    (ange-ftp-error host user
+				    (format "Could not remove directory %s: %s"
+					    dir
+					    (cdr result))))
+	        (ange-ftp-delete-file-entry dir t))
+	    (ange-ftp-real-delete-directory dir recursive trash))))
     (error "Not a directory: %s" dir)))
 
 ;; Make a local copy of FILE and return its name.

lisp/net/tramp-compat.el

@@ -309,6 +309,30 @@ A nil value for either argument stands for the current time."
     (lambda (filename &optional timestamp _flag)
       (set-file-times filename timestamp))))
 
+;; `directory-files' and `directory-files-and-attributes' got argument
+;; COUNT in Emacs 28.1.
+(defalias 'tramp-compat-directory-files
+  (if (equal (tramp-compat-funcall 'func-arity #'directory-files) '(1 . 5))
+      #'directory-files
+    (lambda (directory &optional full match nosort _count)
+      (directory-files directory full match nosort))))
+
+(defalias 'tramp-compat-directory-files-and-attributes
+  (if (equal (tramp-compat-funcall 'func-arity #'directory-files-and-attributes)
+	     '(1 . 6))
+      #'directory-files-and-attributes
+    (lambda (directory &optional full match nosort id-format _count)
+      (directory-files-and-attributes directory full match nosort id-format))))
+
+;; `directory-empty-p' is new in Emacs 28.1.
+(defalias 'tramp-compat-directory-empty-p
+  (if (fboundp 'directory-empty-p)
+      #'directory-empty-p
+    (lambda (dir)
+      (and (file-directory-p dir)
+	   (null (tramp-compat-directory-files
+		  dir nil directory-files-no-dot-files-regexp t 1))))))
+
 (add-hook 'tramp-unload-hook
 	  (lambda ()
 	    (unload-feature 'tramp-loaddefs 'force)
@@ -322,5 +346,8 @@ A nil value for either argument stands for the current time."
 ;;
 ;; * Starting with Emacs 27.1, there's no need to escape open
 ;;   parentheses with a backslash in docstrings anymore.
+;;
+;; * Starting with Emacs 27.1, there's `make-empty-file'.  Could be
+;;   used instead of `write-region'.
 
 ;;; tramp-compat.el ends here

lisp/net/tramp-gvfs.el

@@ -1088,7 +1088,7 @@ file names."
 		  (delete-file file)))
 	      (directory-files
 	       directory 'full directory-files-no-dot-files-regexp))
-      (when (directory-files directory nil directory-files-no-dot-files-regexp)
+      (unless (tramp-compat-directory-empty-p directory)
 	(tramp-error
 	 v 'file-error "Couldn't delete non-empty %s" directory)))
 

lisp/net/tramp-sh.el

@@ -1738,6 +1738,9 @@ ID-FORMAT valid values are `string' and `integer'."
 	    (setcar item (expand-file-name (car item) directory)))
 	  (push item result)))
 
+      (when (natnump count)
+        (setq result (last result count)))
+
       (or (if nosort
 	      result
 	    (sort result (lambda (x y) (string< (car x) (car y)))))

lisp/net/tramp.el

@@ -3145,7 +3145,7 @@ User is always nil."
    (lambda (x)
      (cons x (file-attributes
 	      (if full x (expand-file-name x directory)) id-format)))
-   (directory-files directory full match nosort count)))
+   (tramp-compat-directory-files directory full match nosort count)))
 
 (defun tramp-handle-dired-uncache (dir)
   "Like `dired-uncache' for Tramp files."
@@ -5346,9 +5346,7 @@ BODY is the backend specific code."
     (if (and delete-by-moving-to-trash ,trash)
 	;; Move non-empty dir to trash only if recursive deletion was
 	;; requested.
-	(if (and (not ,recursive)
-		 (directory-files
-		  ,directory nil directory-files-no-dot-files-regexp))
+	(if (not (or ,recursive (tramp-compat-directory-empty-p ,directory)))
 	    (tramp-error
 	     v 'file-error "Directory is not empty, not moving to trash")
 	  (move-file-to-trash ,directory))

test/lisp/net/tramp-tests.el

@@ -2783,8 +2783,9 @@ This tests also `file-directory-p' and `file-accessible-directory-p'."
       (should-not (file-directory-p tmp-name1))
 
       ;; Trashing directories works only since Emacs 27.1.  It doesn't
-      ;; work for crypted remote directories.
-      (when (and (not (tramp--test-crypt-p)) (tramp--test-emacs27-p))
+      ;; work for crypted remote directories and for ange-ftp.
+      (when (and (not (tramp--test-crypt-p)) (not (tramp--test-ftp-p))
+		 (tramp--test-emacs27-p))
 	(let ((trash-directory (tramp--test-make-temp-name 'local quoted))
 	      (delete-by-moving-to-trash t))
 	  (make-directory trash-directory)
@@ -2925,7 +2926,15 @@ This tests also `file-directory-p' and `file-accessible-directory-p'."
 			   '("bla" "foo")))
 	    (should (equal (directory-files
 			    tmp-name1 'full directory-files-no-dot-files-regexp)
-			   `(,tmp-name2 ,tmp-name3))))
+			   `(,tmp-name2 ,tmp-name3)))
+	    ;; Check the COUNT arg.  It exists since Emacs 28.
+	    (when (tramp--test-emacs28-p)
+	      (with-no-warnings
+		(should
+		 (= 1 (length
+		       (directory-files
+			tmp-name1 nil directory-files-no-dot-files-regexp
+			nil 1)))))))
 
 	;; Cleanup.
 	(ignore-errors (delete-directory tmp-name1 'recursive))))))
@@ -3443,7 +3452,13 @@ They might differ only in time attributes or directory size."
 		(file-attributes (car elt)) (cdr elt))))
 
 	    (setq attr (directory-files-and-attributes tmp-name2 nil "\\`b"))
-	    (should (equal (mapcar #'car attr) '("bar" "boz"))))
+	    (should (equal (mapcar #'car attr) '("bar" "boz")))
+
+	    ;; Check the COUNT arg.  It exists since Emacs 28.
+	    (when (tramp--test-emacs28-p)
+	      (with-no-warnings
+		(should (= 1 (length (directory-files-and-attributes
+				      tmp-name2 nil "\\`b" nil nil 1)))))))
 
 	;; Cleanup.
 	(ignore-errors (delete-directory tmp-name1 'recursive))))))