Make cascaded archives working in tramp-archive.el work, again

* lisp/net/tramp-archive.el (tramp-archive-file-name-handler):
Move bindings of `tramp-methods' and `tramp-gvfs-methods' up.
(tramp-archive-file-name-handler): Do not use
`tramp-archive-run-real-handler' for testing existence of
`archive'.  (Bug#79582)

* test/lisp/net/tramp-archive-tests.el
(tramp-archive-test-file-archive-hexlified): Move down.
(tramp-archive-test-cascaded-file-archive)
(tramp-archive-test-cascaded-archive, tramp-archive-test-cascaded):
New defvars.
(tramp-archive--test-deftest-cascaded): New defmacro.
(tramp-archive-test01-file-name-syntax)
(tramp-archive-test05-expand-file-name): Adapt tests.
(tramp-archive-test01-file-name-syntax-cascaded)
(tramp-archive-test05-expand-file-name-cascaded)
(tramp-archive-test06-directory-file-name-cascaded)
(tramp-archive-test07-file-exists-p-cascaded)
(tramp-archive-test08-file-local-copy-cascaded)
(tramp-archive-test09-insert-file-contents-cascaded)
(tramp-archive-test11-copy-file-cascaded)
(tramp-archive-test15-copy-directory-cascaded)
(tramp-archive-test16-directory-files-cascaded)
(tramp-archive-test17-insert-directory-cascaded)
(tramp-archive-test18-file-attributes-cascaded)
(tramp-archive-test19-directory-files-and-attributes-cascaded)
(tramp-archive-test20-file-modes-cascaded)
(tramp-archive-test21-file-links-cascaded)
(tramp-archive-test26-file-name-completion-cascaded)
(tramp-archive-test40-make-nearby-temp-file-cascaded)
(tramp-archive-test43-file-system-info-cascaded)
(tramp-archive-test44-user-group-ids-cascaded): New tests.

* test/lisp/net/tramp-archive-resources/outer.zip: New test file.

lisp/net/tramp-archive.el

@@ -338,15 +338,16 @@ arguments to pass to the OPERATION."
           (tramp-register-file-name-handlers)
           (tramp-archive-run-real-handler operation args))
 
-      (let* ((filename (apply #'tramp-archive-file-name-for-operation
+      (let* ((tramp-methods (cons `(,tramp-archive-method) tramp-methods))
+	     (tramp-gvfs-methods tramp-archive-all-gvfs-methods)
+	     (filename (apply #'tramp-archive-file-name-for-operation
 			      operation args))
 	     (archive (tramp-archive-file-name-archive filename)))
 
         ;; `filename' could be a quoted file name.  Or the file
         ;; archive could be a directory, see Bug#30293.
         (if (or (null archive)
-                (not (tramp-archive-run-real-handler
-                      #'file-exists-p (list archive)))
+                (not (file-exists-p archive))
 	        (tramp-archive-run-real-handler
                  #'file-directory-p (list archive)))
             (tramp-archive-run-real-handler operation args)
@@ -358,9 +359,7 @@ arguments to pass to the OPERATION."
 	      (tramp-get-buffer (tramp-archive-dissect-file-name filename))
 	    (setq default-directory (file-name-as-directory archive)))
           ;; Now run the handler.
-          (let ((tramp-methods (cons `(,tramp-archive-method) tramp-methods))
-	        (tramp-gvfs-methods tramp-archive-all-gvfs-methods)
-	        ;; Set uid and gid.  gvfsd-archive could do it, but it doesn't.
+          (let (;; Set uid and gid.  gvfsd-archive could do it, but it doesn't.
 	        (tramp-unknown-id-integer (user-uid))
 	        (tramp-unknown-id-string (user-login-name))
 	        (fn (assoc operation tramp-archive-file-name-handler-alist)))

test/lisp/net/tramp-archive-tests.el

@@ -36,12 +36,6 @@
 (defvar tramp-archive-test-file-archive (ert-resource-file "foo.tar.gz")
   "The test file archive.")
 
-(defun tramp-archive-test-file-archive-hexlified ()
-    "Return hexlified `tramp-archive-test-file-archive'.
-Do not hexlify \"/\".  This hexlified string is used in `file:///' URLs."
-  (let* ((url-unreserved-chars (cons ?/ url-unreserved-chars)))
-    (url-hexify-string tramp-archive-test-file-archive)))
-
 (defvar tramp-archive-test-archive
   (file-name-as-directory tramp-archive-test-file-archive)
   "The test archive.")
@@ -50,11 +44,28 @@ Do not hexlify \"/\".  This hexlified string is used in `file:///' URLs."
   (file-truename (ert-resource-file "foo.iso"))
   "A directory file name, which looks like an archive.")
 
+(defvar tramp-archive-test-cascaded-file-archive
+  (ert-resource-file "outer.zip/foo.tar.gz")
+  "The cascaded test file archive.")
+
+(defvar tramp-archive-test-cascaded-archive
+  (file-name-as-directory tramp-archive-test-cascaded-file-archive)
+  "The cascaded test archive.")
+
+(defun tramp-archive-test-file-archive-hexlified ()
+    "Return hexlified `tramp-archive-test-file-archive'.
+Do not hexlify \"/\".  This hexlified string is used in `file:///' URLs."
+  (let* ((url-unreserved-chars (cons ?/ url-unreserved-chars)))
+    (url-hexify-string tramp-archive-test-file-archive)))
+
 (setq password-cache-expiry nil
       tramp-cache-read-persistent-data t ;; For auth-sources.
       tramp-persistency-file-name nil
       tramp-verbose 0)
 
+(defvar tramp-archive-test-cascaded nil
+  "Indicator, whether we are testing a cascaded archive.")
+
 (defun tramp-archive--test-make-temp-name ()
   "Return a temporary file name for test.
 The temporary file is not created."
@@ -86,9 +97,29 @@ the origin of the temporary TMPFILE, have no write permissions."
     (file-exists-p tramp-archive-test-file-archive)
     (tramp-archive-file-name-p tramp-archive-test-archive))))
 
+;; These tests are inspired by Bug#79582.
+(defmacro tramp-archive--test-deftest-cascaded (test)
+  "Define ert `TEST-cascaded'."
+  (declare (indent 1))
+  `(ert-deftest ,(intern (concat (symbol-name test) "-cascaded")) ()
+     :tags '(:expensive-test)
+     ;(tramp--test-set-ert-test-documentation ',test "cascaded")
+     (skip-unless tramp-archive-enabled)
+     (if-let* ((ert-test (ert-get-test ',test))
+	       (result (ert-test-most-recent-result ert-test))
+	       (tramp-archive-test-file-archive
+		tramp-archive-test-cascaded-file-archive)
+	       (tramp-archive-test-archive tramp-archive-test-cascaded-archive)
+	       (tramp-archive-test-cascaded t))
+	 (progn
+	   (skip-unless (< (ert-test-result-duration result) 300))
+	   (funcall (ert-test-body ert-test)))
+       (ert-skip (format "Test `%s' must run before" ',test)))))
+
 (ert-deftest tramp-archive-test01-file-name-syntax ()
   "Check archive file name syntax."
-  (should-not (tramp-archive-file-name-p tramp-archive-test-file-archive))
+  (unless tramp-archive-test-cascaded
+    (should-not (tramp-archive-file-name-p tramp-archive-test-file-archive)))
   (should (tramp-archive-file-name-p tramp-archive-test-archive))
   (should
    (string-equal
@@ -136,6 +167,8 @@ the origin of the temporary TMPFILE, have no write permissions."
      (concat tramp-archive-test-archive "baz.tar/"))
     "/")))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test01-file-name-syntax)
+
 (ert-deftest tramp-archive-test02-file-name-dissect ()
   "Check archive file name components."
   (skip-unless tramp-archive-enabled)
@@ -250,10 +283,13 @@ the origin of the temporary TMPFILE, have no write permissions."
    (string-equal
     (expand-file-name (concat tramp-archive-test-archive "./file"))
     (concat tramp-archive-test-archive "file")))
-  (should
-   (string-equal
-    (expand-file-name (concat tramp-archive-test-archive "../file"))
-    (concat (ert-resource-directory) "file"))))
+  (unless tramp-archive-test-cascaded
+    (should
+     (string-equal
+      (expand-file-name (concat tramp-archive-test-archive "../file"))
+      (concat (ert-resource-directory) "file")))))
+
+(tramp-archive--test-deftest-cascaded tramp-archive-test05-expand-file-name)
 
 ;; This test is inspired by Bug#30293.
 (ert-deftest tramp-archive-test05-expand-file-name-non-archive-directory ()
@@ -332,6 +368,8 @@ This checks also `file-name-as-directory', `file-name-directory',
    (unhandled-file-name-directory
     (concat tramp-archive-test-archive "path/to/file"))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test06-directory-file-name)
+
 (ert-deftest tramp-archive-test07-file-exists-p ()
   "Check `file-exist-p', `write-region' and `delete-file'."
   :tags '(:expensive-test)
@@ -355,6 +393,8 @@ This checks also `file-name-as-directory', `file-name-directory',
     ;; Cleanup.
     (tramp-archive-cleanup-hash)))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test07-file-exists-p)
+
 (ert-deftest tramp-archive-test08-file-local-copy ()
   "Check `file-local-copy'."
   :tags '(:expensive-test)
@@ -382,6 +422,8 @@ This checks also `file-name-as-directory', `file-name-directory',
       (ignore-errors (tramp-archive--test-delete tmp-name))
       (tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test08-file-local-copy)
+
 (ert-deftest tramp-archive-test09-insert-file-contents ()
   "Check `insert-file-contents'."
   :tags '(:expensive-test)
@@ -409,6 +451,8 @@ This checks also `file-name-as-directory', `file-name-directory',
 	;; Cleanup.
 	(tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test09-insert-file-contents)
+
 (ert-deftest tramp-archive-test11-copy-file ()
   "Check `copy-file'."
   :tags '(:expensive-test)
@@ -475,6 +519,8 @@ This checks also `file-name-as-directory', `file-name-directory',
       (ignore-errors (tramp-archive--test-delete tmp-name2))
       (tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test11-copy-file)
+
 (ert-deftest tramp-archive-test15-copy-directory ()
   "Check `copy-directory'."
   :tags '(:expensive-test)
@@ -528,6 +574,8 @@ This checks also `file-name-as-directory', `file-name-directory',
       (ignore-errors (tramp-archive--test-delete tmp-name2))
       (tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test15-copy-directory)
+
 (ert-deftest tramp-archive-test16-directory-files ()
   "Check `directory-files'."
   :tags '(:expensive-test)
@@ -552,6 +600,8 @@ This checks also `file-name-as-directory', `file-name-directory',
       ;; Cleanup.
       (tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test16-directory-files)
+
 (ert-deftest tramp-archive-test17-insert-directory ()
   "Check `insert-directory'."
   :tags '(:expensive-test)
@@ -600,6 +650,8 @@ This checks also `file-name-as-directory', `file-name-directory',
       ;; Cleanup.
       (tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test17-insert-directory)
+
 (ert-deftest tramp-archive-test18-file-attributes ()
   "Check `file-attributes'.
 This tests also `access-file', `file-readable-p' and `file-regular-p'."
@@ -661,6 +713,8 @@ This tests also `access-file', `file-readable-p' and `file-regular-p'."
       ;; Cleanup.
       (tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test18-file-attributes)
+
 (ert-deftest tramp-archive-test19-directory-files-and-attributes ()
   "Check `directory-files-and-attributes'."
   :tags '(:expensive-test)
@@ -686,6 +740,9 @@ This tests also `access-file', `file-readable-p' and `file-regular-p'."
       ;; Cleanup.
       (tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded
+ tramp-archive-test19-directory-files-and-attributes)
+
 (ert-deftest tramp-archive-test20-file-modes ()
   "Check `file-modes'.
 This tests also `file-executable-p', `file-writable-p' and `set-file-modes'."
@@ -717,6 +774,8 @@ This tests also `file-executable-p', `file-writable-p' and `set-file-modes'."
       ;; Cleanup.
       (tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test20-file-modes)
+
 (ert-deftest tramp-archive-test21-file-links ()
   "Check `file-symlink-p' and `file-truename'"
   :tags '(:expensive-test)
@@ -758,6 +817,8 @@ This tests also `file-executable-p', `file-writable-p' and `set-file-modes'."
       ;; Cleanup.
       (tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test21-file-links)
+
 (ert-deftest tramp-archive-test26-file-name-completion ()
   "Check `file-name-completion' and `file-name-all-completions'."
   :tags '(:expensive-test)
@@ -797,6 +858,8 @@ This tests also `file-executable-p', `file-writable-p' and `set-file-modes'."
       ;; Cleanup.
       (tramp-archive-cleanup-hash))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test26-file-name-completion)
+
 (ert-deftest tramp-archive-test40-make-nearby-temp-file ()
   "Check `make-nearby-temp-file' and `temporary-file-directory'."
   (skip-unless tramp-archive-enabled)
@@ -824,6 +887,8 @@ This tests also `file-executable-p', `file-writable-p' and `set-file-modes'."
     (delete-directory tmp-file)
     (should-not (file-exists-p tmp-file))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test40-make-nearby-temp-file)
+
 (ert-deftest tramp-archive-test43-file-system-info ()
   "Check that `file-system-info' returns proper values."
   (skip-unless tramp-archive-enabled)
@@ -837,6 +902,8 @@ This tests also `file-executable-p', `file-writable-p' and `set-file-modes'."
 		 (zerop (nth 1 fsi))
 		 (zerop (nth 2 fsi))))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test43-file-system-info)
+
 ;; `file-user-uid' and `file-group-gid' were introduced in Emacs 30.1.
 (ert-deftest tramp-archive-test44-user-group-ids ()
   "Check results of user/group functions.
@@ -856,6 +923,8 @@ This tests also `file-executable-p', `file-writable-p' and `set-file-modes'."
       (should (equal uid (with-no-warnings (file-user-uid))))
       (should (equal gid (with-no-warnings (file-group-gid)))))))
 
+(tramp-archive--test-deftest-cascaded tramp-archive-test44-user-group-ids)
+
 (ert-deftest tramp-archive-test50-auto-load ()
   "Check that `tramp-archive' autoloads properly."
   :tags '(:expensive-test)