Improve performance of 'file-name-case-insensitive-p' for Tramp files

Previously, each function in 'tramp-foreign-file-name-handler-alist'
would call 'tramp-dissect-file-name', resulting in it being called
several times whenever 'tramp-find-foreign-file-name-handler' was
called.  Now, functions take the dissected file name to avoid this
duplicated effort.  (Bug#51699)

* etc/NEWS: Announce this change.

* lisp/net/tramp-adb.el (tramp-adb-file-name-p):
* lisp/net/tramp-ftp.el (tramp-ftp-file-name-p):
* lisp/net/tramp-gvfs.el (tramp-gvfs-file-name-p):
* lisp/net/tramp-rclone.el (tramp-rclone-file-name-p):
* lisp/net/tramp-smb.el (tramp-smb-file-name-p):
* lisp/net/tramp-sshfs.el (tramp-sshfs-file-name-p):
* lisp/net/tramp-sudoedit.el (tramp-sudoedit-file-name-p):
Accept dissected file names.

* lisp/net/tramp.el (tramp-ensure-dissected-file-name): New function.
(tramp-find-foreign-file-name-handler): Pass dissected file name to
functions.
(tramp-connectable-p): Use 'tramp-ensure-dissected-file-name'.

etc/NEWS

@@ -532,6 +532,12 @@ get proper locale-dependent downcasing, the string has to be converted
 to multibyte first.  (This goes for the other case-changing functions,
 too.)
 
+---
+** Functions in 'tramp-foreign-file-name-handler-alist' have changed.
+Functions to determine which Tramp file name handler to use are now
+passed a file name in dissected form (via 'tramp-dissect-file-name')
+instead of in string form.
+
 ---
 ** 'def' indentation changes.
 In 'emacs-lisp-mode', forms with a symbol with a name that start with

lisp/net/tramp-adb.el

@@ -191,11 +191,10 @@ It is used for TCP/IP devices."
 ;; It must be a `defsubst' in order to push the whole code into
 ;; tramp-loaddefs.el.  Otherwise, there would be recursive autoloading.
 ;;;###tramp-autoload
-(defsubst tramp-adb-file-name-p (filename)
-  "Check if it's a FILENAME for ADB."
-  (and (tramp-tramp-file-p filename)
-       (string= (tramp-file-name-method (tramp-dissect-file-name filename))
-		tramp-adb-method)))
+(defsubst tramp-adb-file-name-p (vec-or-filename)
+  "Check if it's a VEC-OR-FILENAME for ADB."
+  (when-let* ((vec (tramp-ensure-dissected-file-name vec-or-filename)))
+    (string= (tramp-file-name-method vec) tramp-adb-method)))
 
 ;;;###tramp-autoload
 (defun tramp-adb-file-name-handler (operation &rest args)

lisp/net/tramp-ftp.el

@@ -175,11 +175,10 @@ pass to the OPERATION."
 ;; It must be a `defsubst' in order to push the whole code into
 ;; tramp-loaddefs.el.  Otherwise, there would be recursive autoloading.
 ;;;###tramp-autoload
-(defsubst tramp-ftp-file-name-p (filename)
-  "Check if it's a FILENAME that should be forwarded to Ange-FTP."
-  (and (tramp-tramp-file-p filename)
-       (string= (tramp-file-name-method (tramp-dissect-file-name filename))
-		tramp-ftp-method)))
+(defsubst tramp-ftp-file-name-p (vec-or-filename)
+  "Check if it's a VEC-OR-FILENAME that should be forwarded to Ange-FTP."
+  (when-let* ((vec (tramp-ensure-dissected-file-name vec-or-filename)))
+    (string= (tramp-file-name-method vec) tramp-ftp-method)))
 
 ;;;###tramp-autoload
 (tramp--with-startup

lisp/net/tramp-gvfs.el

@@ -834,12 +834,11 @@ Operations not mentioned here will be handled by the default Emacs primitives.")
 ;; It must be a `defsubst' in order to push the whole code into
 ;; tramp-loaddefs.el.  Otherwise, there would be recursive autoloading.
 ;;;###tramp-autoload
-(defsubst tramp-gvfs-file-name-p (filename)
-  "Check if it's a FILENAME handled by the GVFS daemon."
-  (and (tramp-tramp-file-p filename)
-       (let ((method
-	      (tramp-file-name-method (tramp-dissect-file-name filename))))
-	 (and (stringp method) (member method tramp-gvfs-methods)))))
+(defsubst tramp-gvfs-file-name-p (vec-or-filename)
+  "Check if it's a VEC-OR-FILENAME handled by the GVFS daemon."
+  (when-let* ((vec (tramp-ensure-dissected-file-name vec-or-filename)))
+    (let ((method (tramp-file-name-method vec)))
+      (and (stringp method) (member method tramp-gvfs-methods)))))
 
 ;;;###tramp-autoload
 (defun tramp-gvfs-file-name-handler (operation &rest args)

lisp/net/tramp-rclone.el

@@ -156,11 +156,10 @@ Operations not mentioned here will be handled by the default Emacs primitives.")
 ;; It must be a `defsubst' in order to push the whole code into
 ;; tramp-loaddefs.el.  Otherwise, there would be recursive autoloading.
 ;;;###tramp-autoload
-(defsubst tramp-rclone-file-name-p (filename)
-  "Check if it's a FILENAME for rclone."
-  (and (tramp-tramp-file-p filename)
-       (string= (tramp-file-name-method (tramp-dissect-file-name filename))
-		tramp-rclone-method)))
+(defsubst tramp-rclone-file-name-p (vec-or-filename)
+  "Check if it's a VEC-OR-FILENAME for rclone."
+  (when-let* ((vec (tramp-ensure-dissected-file-name vec-or-filename)))
+    (string= (tramp-file-name-method vec) tramp-rclone-method)))
 
 ;;;###tramp-autoload
 (defun tramp-rclone-file-name-handler (operation &rest args)

lisp/net/tramp-smb.el

@@ -330,11 +330,10 @@ This can be used to disable echo etc."
 ;; It must be a `defsubst' in order to push the whole code into
 ;; tramp-loaddefs.el.  Otherwise, there would be recursive autoloading.
 ;;;###tramp-autoload
-(defsubst tramp-smb-file-name-p (filename)
-  "Check if it's a FILENAME for SMB servers."
-  (and (tramp-tramp-file-p filename)
-       (string= (tramp-file-name-method (tramp-dissect-file-name filename))
-		tramp-smb-method)))
+(defsubst tramp-smb-file-name-p (vec-or-filename)
+  "Check if it's a VEC-OR-FILENAME for SMB servers."
+  (when-let* ((vec (tramp-ensure-dissected-file-name vec-or-filename)))
+    (string= (tramp-file-name-method vec) tramp-smb-method)))
 
 ;;;###tramp-autoload
 (defun tramp-smb-file-name-handler (operation &rest args)

lisp/net/tramp-sshfs.el

@@ -156,11 +156,10 @@ Operations not mentioned here will be handled by the default Emacs primitives.")
 ;; It must be a `defsubst' in order to push the whole code into
 ;; tramp-loaddefs.el.  Otherwise, there would be recursive autoloading.
 ;;;###tramp-autoload
-(defsubst tramp-sshfs-file-name-p (filename)
-  "Check if it's a FILENAME for sshfs."
-  (and (tramp-tramp-file-p filename)
-       (string= (tramp-file-name-method (tramp-dissect-file-name filename))
-	        tramp-sshfs-method)))
+(defsubst tramp-sshfs-file-name-p (vec-or-filename)
+  "Check if it's a VEC-OR-FILENAME for sshfs."
+  (when-let* ((vec (tramp-ensure-dissected-file-name vec-or-filename)))
+    (string= (tramp-file-name-method vec) tramp-sshfs-method)))
 
 ;;;###tramp-autoload
 (defun tramp-sshfs-file-name-handler (operation &rest args)

lisp/net/tramp-sudoedit.el

@@ -148,11 +148,10 @@ See `tramp-actions-before-shell' for more info.")
 ;; It must be a `defsubst' in order to push the whole code into
 ;; tramp-loaddefs.el.  Otherwise, there would be recursive autoloading.
 ;;;###tramp-autoload
-(defsubst tramp-sudoedit-file-name-p (filename)
-  "Check if it's a FILENAME for SUDOEDIT."
-  (and (tramp-tramp-file-p filename)
-       (string= (tramp-file-name-method (tramp-dissect-file-name filename))
-		tramp-sudoedit-method)))
+(defsubst tramp-sudoedit-file-name-p (vec-or-filename)
+  "Check if it's a VEC-OR-FILENAME for SUDOEDIT."
+  (when-let* ((vec (tramp-ensure-dissected-file-name vec-or-filename)))
+    (string= (tramp-file-name-method vec) tramp-sudoedit-method)))
 
 ;;;###tramp-autoload
 (defun tramp-sudoedit-file-name-handler (operation &rest args)

lisp/net/tramp.el

@@ -1669,6 +1669,16 @@ default values are used."
 
 (put #'tramp-dissect-file-name 'tramp-suppress-trace t)
 
+(defun tramp-ensure-dissected-file-name (vec-or-filename)
+  "Return a `tramp-file-name' structure for VEC-OR-FILENAME.
+
+VEC-OR-FILENAME may be either a string or a `tramp-file-name'.
+If it's not a Tramp filename, return nil."
+  (cond
+   ((tramp-file-name-p vec-or-filename) vec-or-filename)
+   ((tramp-tramp-file-p vec-or-filename)
+    (tramp-dissect-file-name vec-or-filename))))
+
 (defun tramp-dissect-hop-name (name &optional nodefault)
   "Return a `tramp-file-name' structure of `hop' part of NAME.
 See `tramp-dissect-file-name' for details."
@@ -2552,11 +2562,14 @@ Must be handled by the callers."
   "Return foreign file name handler if exists."
   (when (tramp-tramp-file-p filename)
     (let ((handler tramp-foreign-file-name-handler-alist)
+          (vec (tramp-dissect-file-name filename))
 	  elt res)
       (while handler
 	(setq elt (car handler)
 	      handler (cdr handler))
-	(when (funcall (car elt) filename)
+        ;; Previously, this function was called with FILENAME, but now
+        ;; it's called with the VEC.
+        (when (with-demoted-errors "Error: %S" (funcall (car elt) vec))
 	  (setq handler nil
 		res (cdr elt))))
       res)))
@@ -2755,8 +2768,9 @@ remote file names."
 (defun tramp-register-foreign-file-name-handler
     (func handler &optional append)
   "Register (FUNC . HANDLER) in `tramp-foreign-file-name-handler-alist'.
-FUNC is the function, which determines whether HANDLER is to be called.
-Add operations defined in `HANDLER-alist' to `tramp-file-name-handler'."
+FUNC is the function, which takes a dissected filename and determines
+whether HANDLER is to be called.  Add operations defined in
+`HANDLER-alist' to `tramp-file-name-handler'."
   (add-to-list
    'tramp-foreign-file-name-handler-alist `(,func . ,handler) append)
   ;; Mark `operations' the handler is responsible for.
@@ -2814,11 +2828,7 @@ They are completed by \"M-x TAB\" only if the current buffer is remote."
 This is true, if either the remote host is already connected, or if we are
 not in completion mode."
   (let ((tramp-verbose 0)
-	(vec
-	 (cond
-	  ((tramp-file-name-p vec-or-filename) vec-or-filename)
-	  ((tramp-tramp-file-p vec-or-filename)
-	   (tramp-dissect-file-name vec-or-filename)))))
+	(vec (tramp-ensure-dissected-file-name vec-or-filename)))
     (or ;; We check this for the process related to
 	;; `tramp-buffer-name'; otherwise `start-file-process'
 	;; wouldn't run ever when `non-essential' is non-nil.