Fix 'expand-file-name' for remote files

This reverts most of commit 14fb657ba82da346d36f05f88da26f1c5498b798
and its followup fixes, and instead fixes the original bugs in a
different manner that doesn't affect any unrelated use cases.  As
part of this, the code which caused 'expand-file-name' to enforce
a trailing slash on expanded directories is removed, as this kind
of semantic processing is outside of 'expand-file-name's scope.
* src/fileio.c (Fexpand_file_name): If expanding default_directory
yields a remote file name, call its handlers.  (Bug#26911)
(Bug#34834)

* doc/lispref/files.texi (File Name Expansion): Remove the
requirement that expanding a directory name yields a directory
name, i.e. that the expansion must end in a slash.

* etc/NEWS: Remove the announcement of the changed behavior of
'expand-file-name' wrt trailing slashes.

* test/src/fileio-tests.el (fileio-tests--HOME-trailing-slash)
(fileio-tests--expand-file-name-trailing-slash): Remove tests.
* test/lisp/net/tramp-tests.el (tramp-test05-expand-file-name): No
need to expect different results in Emacs 28 and later.

1 files changed, 0 insertions, 37 deletions

diff --git a/test/src/fileio-tests.el b/test/src/fileio-tests.el
index bedda83bbdb..ed381d151ee 100644
--- a/test/src/fileio-tests.el
+++ b/test/src/fileio-tests.el
@@ -107,43 +107,6 @@ Also check that an encoding error can appear in a symlink."
       (setenv "HOME" "x:foo")
       (should (equal (expand-file-name "~/bar") "x:/foo/bar")))))
 
-(ert-deftest fileio-tests--HOME-trailing-slash ()
-  "Test that expand-file-name of \"~\" respects trailing slash."
-  :expected-result (if (memq system-type '(windows-nt ms-dos))
-                       :failed
-                     :passed)
-  (let ((process-environment (copy-sequence process-environment)))
-    (dolist (home
-             (if (memq system-type '(windows-nt ms-dos))
-                 '("c:/a/b/c" "c:/a/b/c/")
-               '("/a/b/c" "/a/b/c/")))
-      (setenv "HOME" home)
-      (should (equal (expand-file-name "~") (expand-file-name home))))))
-
-(ert-deftest fileio-tests--expand-file-name-trailing-slash ()
-  (dolist (fooslashalias '("foo/" "foo//" "foo/." "foo//." "foo///././."
-                           "foo/a/.."))
-    (if (memq system-type '(windows-nt ms-dos))
-        (progn
-          (should (equal (expand-file-name fooslashalias "c:/") "c:/foo/"))
-          (should (equal (expand-file-name (concat "c:/" fooslashalias))
-                         "c:/foo/"))
-          (should (equal (expand-file-name "." "c:/usr/spool/")
-                         "c:/usr/spool/"))
-          (should (equal (expand-file-name "" "c:/usr/spool/")
-                         "c:/usr/spool/")))
-      (should (equal (expand-file-name fooslashalias "/") "/foo/"))
-      (should (equal (expand-file-name (concat "/" fooslashalias)) "/foo/"))
-      (should (equal (expand-file-name "." "/usr/spool/") "/usr/spool/"))
-      (should (equal (expand-file-name "" "/usr/spool/") "/usr/spool/"))))
-  ;; Trailing "B/C/.." means B must be a directory.
-  (if (memq system-type '(windows-nt ms-dos))
-      (progn
-        (should (equal (expand-file-name "c:/a/b/c/..") "c:/a/b/"))
-        (should (equal (expand-file-name "c:/a/b/c/../") "c:/a/b/")))
-    (should (equal (expand-file-name "/a/b/c/..") "/a/b/"))
-    (should (equal (expand-file-name "/a/b/c/../") "/a/b/"))))
-
 (ert-deftest fileio-tests--insert-file-interrupt ()
   (let ((text "-*- coding: binary -*-\n\xc3\xc3help")
         f)