Don’t adjust CRLF in file names

* doc/misc/gnus.texi (Non-ASCII Group Names):
* etc/NEWS:
* test/lisp/net/tramp-tests.el (tramp--test-utf8):
Use utf-8-unix, not utf-8, for default-file-name-coding-system, so
that CRLF in file names is left alone.
* lisp/international/mule-cmds.el (set-default-coding-systems):
Do not alter CRLF in file name coding systems.
(prefer-coding-system): Ignore differences in CRLF processing when
checking whether we used the user-specified file name coding system.
* test/src/fileio-tests.el: New file.

1 files changed, 49 insertions, 0 deletions

diff --git a/test/src/fileio-tests.el b/test/src/fileio-tests.el
new file mode 100644
index 00000000000..75aca7d0ab8
--- /dev/null
+++ b/test/src/fileio-tests.el
@@ -0,0 +1,49 @@
+;;; unit tests for src/fileio.c      -*- lexical-binding: t; -*-
+
+;; Copyright 2017 Free Software Foundation, Inc.
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
+
+(require 'ert)
+
+(defun try-char (char link)
+  (let ((target (string char)))
+    (make-symbolic-link target link)
+    (let* ((read-link (file-symlink-p link))
+           (failure (unless (string-equal target read-link)
+                      (list 'string-equal target read-link))))
+      (delete-file link)
+      failure)))
+
+(defun fileio-tests--symlink-failure ()
+  (let* ((dir (make-temp-file "fileio" t))
+         (link (expand-file-name "link" dir)))
+    (unwind-protect
+        (let ((failure
+               (let ((default-file-name-coding-system 'utf-8-unix))
+                 (try-char (unibyte-char-to-multibyte 128) link)))
+              (char 0))
+          (while (and (not failure) (< char 300))
+            (setq char (1+ char))
+            (unless (= char ?~)
+              (setq failure (try-char char link))))
+          failure)
+      (delete-directory dir t))))
+
+(ert-deftest fileio-tests--odd-symlink-chars ()
+  "Check that any non-NULL ASCII character can appear in a symlink.
+Also check that an encoding error can appear in a symlink."
+  (should (equal nil (fileio-tests--symlink-failure))))