Don't downcase system diagnostics' first letters

* etc/NEWS: Document this.
* lisp/emacs-lisp/bytecomp.el (byte-compile-file):
* lisp/ffap.el (find-file-at-point):
* lisp/files.el (insert-file-1):
* lisp/net/ange-ftp.el (ange-ftp-barf-if-not-directory)
(ange-ftp-copy-file-internal):
* lisp/progmodes/etags.el (visit-tags-table):
* lisp/url/url-dav.el (url-dav-delete-directory, url-dav-delete-file)
(url-dav-directory-files):
Keep diagnostics consistent with system's.
* lisp/erc/erc-dcc.el (erc-dcc-server):
* lisp/ffap.el (ffap-machine-p):
Ignore case while comparing diagnostics.
* src/fileio.c (report_file_errno): Don't downcase, and simplify.
Fixes: bug#19642

14 files changed, 61 insertions, 44 deletions

diff --git a/etc/ChangeLog b/etc/ChangeLog
index 7b64dfb9153..47f61f4d7fd 100644
--- a/etc/ChangeLog
+++ b/etc/ChangeLog
@@ -1,3 +1,8 @@
+2015-01-22  Paul Eggert  <eggert@cs.ucla.edu>
+
+	Don't downcase system diagnostics' first letters
+	* NEWS: Document this.
+
 2015-01-16  Artur Malabarba  <bruce.connor.am@gmail.com>
 
 	* NEWS: Document installing packages from directories.
diff --git a/etc/NEWS b/etc/NEWS
index 120d8b920c6..db47033fb35 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -538,6 +538,11 @@ position list returned for such events is now nil.
 These slots used to hold key-shortcut data, but have been obsolete since
 Emacs-21.
 
+** Emacs no longer downcases the first letter of a system diagnostic
+when signaling a file error.  For example, it now reports "Permission
+denied" instead of "permission denied".  The old behavior was problematic
+in languages like German where downcasing rules depend on grammar.
+
 
 * Lisp Changes in Emacs 25.1
 
diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index c000d6bb9a6..5cceb19ff1a 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,16 @@
+2015-01-22  Paul Eggert  <eggert@cs.ucla.edu>
+
+	Don't downcase system diagnostics' first letters
+	* emacs-lisp/bytecomp.el (byte-compile-file):
+	* ffap.el (find-file-at-point):
+	* files.el (insert-file-1):
+	* net/ange-ftp.el (ange-ftp-barf-if-not-directory)
+	(ange-ftp-copy-file-internal):
+	* progmodes/etags.el (visit-tags-table):
+	Keep diagnostics consistent with system's.
+	* ffap.el (ffap-machine-p):
+	Ignore case while comparing diagnostics.
+
 2015-01-22  Stefan Monnier  <monnier@iro.umontreal.ca>
 
 	* help.el (help-make-usage): Don't turn a "_" arg into an empty-string
diff --git a/lisp/emacs-lisp/bytecomp.el b/lisp/emacs-lisp/bytecomp.el
index 8440570d755..2bd8d07851b 100644
--- a/lisp/emacs-lisp/bytecomp.el
+++ b/lisp/emacs-lisp/bytecomp.el
@@ -1863,8 +1863,8 @@ The value is non-nil if there were no errors, nil if errors."
 	    (signal 'file-error
 		    (list "Opening output file"
 			  (if (file-exists-p target-file)
-			      "cannot overwrite file"
-			    "directory not writable or nonexistent")
+			      "Cannot overwrite file"
+			    "Directory not writable or nonexistent")
 			  target-file)))
 	  (kill-buffer (current-buffer)))
 	(if (and byte-compile-generate-call-tree
diff --git a/lisp/erc/ChangeLog b/lisp/erc/ChangeLog
index 1b54fb6a48d..28ac7d38b96 100644
--- a/lisp/erc/ChangeLog
+++ b/lisp/erc/ChangeLog
@@ -1,3 +1,8 @@
+2015-01-22  Paul Eggert  <eggert@cs.ucla.edu>
+
+	Don't downcase system diagnostics' first letters
+	* erc-dcc.el (erc-dcc-server): Ignore case while comparing diagnostics.
+
 2014-11-23  Michael Albinus  <michael.albinus@gmx.de>
 
 	* erc-desktop-notifications.el (erc-notifications-bus):
diff --git a/lisp/erc/erc-dcc.el b/lisp/erc/erc-dcc.el
index 9d52c3b7c09..182f1e05921 100644
--- a/lisp/erc/erc-dcc.el
+++ b/lisp/erc/erc-dcc.el
@@ -379,7 +379,7 @@ created subprocess, or nil."
                   (set-process-filter-multibyte process nil)))))
         (file-error
          (unless (and (string= "Cannot bind server socket" (nth 1 err))
-                      (string= "address already in use" (nth 2 err)))
+                      (string= "address already in use" (downcase (nth 2 err))))
            (signal (car err) (cdr err)))
          (setq port (1+ port))
          (unless (< port upper)
@@ -1264,4 +1264,3 @@ other client."
 ;; Local Variables:
 ;; indent-tabs-mode: nil
 ;; End:
-
diff --git a/lisp/ffap.el b/lisp/ffap.el
index 1b8ea60e03b..350a6bdac20 100644
--- a/lisp/ffap.el
+++ b/lisp/ffap.el
@@ -476,7 +476,7 @@ Returned values:
 	      ;; (file-error "connection failed" "address already in use"
 	      ;;	     "ftp.uu.net" "ffap-machine-p")
 	      ((equal mesg "connection failed")
-	       (if (equal (nth 2 error) "permission denied")
+	       (if (string= (downcase (nth 2 error)) "permission denied")
 		   nil			; host does not exist
 		 ;; Other errors mean the host exists:
 		 (nth 2 error)))
@@ -1439,7 +1439,7 @@ and the functions `ffap-file-at-point' and `ffap-url-at-point'."
 		 (expand-file-name filename)))
        ;; User does not want to find a non-existent file:
        ((signal 'file-error (list "Opening file buffer"
-				  "no such file or directory"
+				  "No such file or directory"
 				  filename)))))))
 
 ;; Shortcut: allow {M-x ffap} rather than {M-x find-file-at-point}.
diff --git a/lisp/files.el b/lisp/files.el
index e9632edacef..ed1943dfc28 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -2128,7 +2128,7 @@ This function ensures that none of these modifications will take place."
 
 (defun insert-file-1 (filename insert-func)
   (if (file-directory-p filename)
-      (signal 'file-error (list "Opening input file" "file is a directory"
+      (signal 'file-error (list "Opening input file" "Is a directory"
                                 filename)))
   ;; Check whether the file is uncommonly large
   (abort-if-file-too-large (nth 7 (file-attributes filename)) "insert" filename)
diff --git a/lisp/net/ange-ftp.el b/lisp/net/ange-ftp.el
index 17db6e76ec9..52153ad8322 100644
--- a/lisp/net/ange-ftp.el
+++ b/lisp/net/ange-ftp.el
@@ -1536,8 +1536,8 @@ then kill the related FTP process."
       (signal 'file-error
 	      (list "Opening directory"
 		    (if (file-exists-p directory)
-			"not a directory"
-		      "no such file or directory")
+			"Not a directory"
+		      "No such file or directory")
 		    directory))))
 
 ;;;; ------------------------------------------------------------
@@ -3664,7 +3664,7 @@ so return the size on the remote host exactly. See RFC 3659."
 
   (or (file-exists-p filename)
       (signal 'file-error
-	      (list "Copy file" "no such file or directory" filename)))
+	      (list "Copy file" "No such file or directory" filename)))
 
   ;; canonicalize newname if a directory.
   (if (file-directory-p newname)
diff --git a/lisp/progmodes/etags.el b/lisp/progmodes/etags.el
index 626855ecdd4..b470352f8dc 100644
--- a/lisp/progmodes/etags.el
+++ b/lisp/progmodes/etags.el
@@ -308,7 +308,7 @@ file the tag was in."
     (save-excursion
       (or (visit-tags-table-buffer file)
 	  (signal 'file-error (list "Visiting tags table"
-				    "file does not exist"
+				    "No such file or directory"
 				    file)))
       ;; Set FILE to the expanded name.
       (setq file tags-file-name)))
diff --git a/lisp/url/ChangeLog b/lisp/url/ChangeLog
index 1f5ece02113..920d692d319 100644
--- a/lisp/url/ChangeLog
+++ b/lisp/url/ChangeLog
@@ -1,3 +1,9 @@
+2015-01-22  Paul Eggert  <eggert@cs.ucla.edu>
+
+	Don't downcase system diagnostics' first letters
+	* url-dav.el (url-dav-delete-directory, url-dav-delete-file)
+	(url-dav-directory-files): Keep diagnostics consistent with system's.
+
 2014-12-12  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
 	* url-http.el (url-http-parse-headers): `gnutls-available-p' is
diff --git a/lisp/url/url-dav.el b/lisp/url/url-dav.el
index 65747e93000..61ca0885ec5 100644
--- a/lisp/url/url-dav.el
+++ b/lisp/url/url-dav.el
@@ -741,7 +741,7 @@ files in the collection as well."
 		 (if (and (not recursive)
 			  (/= (length props) 1))
 		     (signal 'file-error (list "Removing directory"
-					       "directory not empty" url)))))
+					       "Directory not empty" url)))))
 
      (mapc (lambda (result)
 	     (setq status (plist-get (cdr result) 'DAV:status))
@@ -760,7 +760,7 @@ files in the collection as well."
 		 url lock-token
 		 (setq props (url-dav-get-properties url))
 		 (if (eq (plist-get (cdar props) 'DAV:resourcetype) 'DAV:collection)
-		     (signal 'file-error (list "Removing old name" "is a collection" url)))))
+		     (signal 'file-error (list "Removing old name" "Is a collection" url)))))
 
     (mapc (lambda (result)
 	    (setq status (plist-get (cdr result) 'DAV:status))
@@ -787,7 +787,7 @@ If NOSORT is non-nil, the list is not sorted--its order is unpredictable.
 
     (when (and (= (length properties) 1)
 	       (not (url-dav-file-directory-p url)))
-      (signal 'file-error (list "Opening directory" "not a directory" url)))
+      (signal 'file-error (list "Opening directory" "Not a directory" url)))
 
     (while properties
       (setq child-props (pop properties)
diff --git a/src/ChangeLog b/src/ChangeLog
index 4c5b2a1397a..8f23dd3833e 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,9 @@
 2015-01-22  Paul Eggert  <eggert@cs.ucla.edu>
 
+	Don't downcase system diagnostics' first letters
+	* fileio.c (report_file_errno): Don't downcase, and simplify.
+	Fixes: bug#19642
+
 	Isolate NIL_IS_ZERO-assuming code better
 	Suggested by Stefan Monnier in:
 	http://lists.gnu.org/archive/html/emacs-devel/2015-01/msg00588.html
diff --git a/src/fileio.c b/src/fileio.c
index ff6720d4ae2..d0fd08a742e 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -186,37 +186,17 @@ void
 report_file_errno (char const *string, Lisp_Object name, int errorno)
 {
   Lisp_Object data = CONSP (name) || NILP (name) ? name : list1 (name);
-  Lisp_Object errstring;
-  char *str;
-
   synchronize_system_messages_locale ();
-  str = strerror (errorno);
-  errstring = code_convert_string_norecord (build_unibyte_string (str),
-					    Vlocale_coding_system, 0);
-
-  while (1)
-    switch (errorno)
-      {
-      case EEXIST:
-	xsignal (Qfile_already_exists, Fcons (errstring, data));
-	break;
-      default:
-	/* System error messages are capitalized.  Downcase the initial
-	   unless it is followed by a slash.  (The slash case caters to
-	   error messages that begin with "I/O" or, in German, "E/A".)  */
-	if (STRING_MULTIBYTE (errstring)
-	    && ! EQ (Faref (errstring, make_number (1)), make_number ('/')))
-	  {
-	    int c;
-
-	    str = SSDATA (errstring);
-	    c = STRING_CHAR ((unsigned char *) str);
-	    Faset (errstring, make_number (0), make_number (downcase (c)));
-	  }
-
-	xsignal (Qfile_error,
-		 Fcons (build_string (string), Fcons (errstring, data)));
-      }
+  char *str = strerror (errorno);
+  Lisp_Object errstring
+    = code_convert_string_norecord (build_unibyte_string (str),
+				    Vlocale_coding_system, 0);
+  Lisp_Object errdata = Fcons (errstring, data);
+
+  if (errorno == EEXIST)
+    xsignal (Qfile_already_exists, errdata);
+  else
+    xsignal (Qfile_error, Fcons (build_string (string), errdata));
 }
 
 /* Signal a file-access failure that set errno.  STRING describes the