bug#23670: 24.5; error when complete coding system

[Glenn Morris <rgm@gnu.org>]

Version: 26.1

ynyaaa@gmail.com wrote:

> Type C-x RET f utf- SPC, then an error occurs.
>
> Internal error: utf-7-imap doesn't match \`utf\(.*?\)-\([-_./:| *]\|\([[:alpha:]]\)[[:digit:]]*?\)-

Thanks; fixed.

commit 79abec2
Date:   Wed Mar 1 16:53:08 2017 -0500

    Fix for coding-system completion (bug#23670)
    
    * lisp/international/mule.el (read-buffer-file-coding-system):
    Ensure that completion-pcm--delim-wild-regex is enclosed in parens,
    so that completion-pcm--pattern->regex can append "*?".

diff --git a/lisp/international/mule.el b/lisp/international/mule.el
index 8754f7f..fa3ad80 100644
--- a/lisp/international/mule.el
+++ b/lisp/international/mule.el
@@ -1311,8 +1311,8 @@ Internal use only.")
                                     preferred))))))
          (completion-ignore-case t)
          (completion-pcm--delim-wild-regex ; Let "u8" complete to "utf-8".
-          (concat completion-pcm--delim-wild-regex
-                  "\\|\\([[:alpha:]]\\)[[:digit:]]"))
+          (concat "\\(?:" completion-pcm--delim-wild-regex
+                  "\\|\\([[:alpha:]]\\)[[:digit:]]\\)"))
          (cs (completing-read
               (format "Coding system for saving file (default %s): " default)
               combined-table