2019-03-26 regex cleanup

Problems reported by Mattias Engdegård in:
https://lists.gnu.org/r/emacs-devel/2019-03/msg01028.html
* lisp/align.el (align-rules-list):
* lisp/speedbar.el (speedbar-check-read-only, speedbar-check-vc):
* lisp/vc/diff-mode.el (diff-add-change-log-entries-other-window):
* lisp/woman.el (woman-parse-numeric-arg):
Put "-" at end of character alternatives, since a range was not intended.
* lisp/erc/erc.el (font-lock):
* lisp/mail/footnote.el (cl-seq):
Avoid duplicate character alternatives by using cl-seq API.
* lisp/mail/footnote.el (footnote--current-regexp):
* lisp/textmodes/css-mode.el (css--font-lock-keywords):
Avoid repetition of repetition.
* lisp/net/webjump.el (webjump-url-encode):
Add ~ to character alternatives, and rewrite confusing range.
* lisp/progmodes/verilog-mode.el (verilog-compiler-directives)
(verilog-assignment-operator-re):
Remove duplicate.
* lisp/progmodes/verilog-mode.el (verilog-preprocessor-re):
* lisp/textmodes/css-mode.el (css--font-lock-keywords):
Don’t escape a char that doesn’t need it.
* lisp/textmodes/picture.el (picture-tab-chars): In docstring,
do not say regexp characters will be quoted; merely say in
another way that the syntax is that of character alternatives.
(picture-set-tab-stops, picture-tab-search): Don’t attempt
to regexp-quote picture-tab-chars.
(picture-tab-search): Quote \ in picture-tab-chars for
skip-chars-backwards, which treats \ differently than
regexp character alternatives do.

1 files changed, 3 insertions, 4 deletions

diff --git a/lisp/erc/erc.el b/lisp/erc/erc.el
index bcaa3e45258..e34487de273 100644
--- a/lisp/erc/erc.el
+++ b/lisp/erc/erc.el
@@ -67,6 +67,7 @@
 (load "erc-loaddefs" nil t)
 
 (eval-when-compile (require 'cl-lib))
+(require 'cl-seq)
 (require 'font-lock)
 (require 'pp)
 (require 'thingatpt)
@@ -2522,10 +2523,8 @@ Returns NICK unmodified unless `erc-lurker-trim-nicks' is
 non-nil."
   (if erc-lurker-trim-nicks
       (replace-regexp-in-string
-       (format "[%s]"
-               (mapconcat (lambda (char)
-                            (regexp-quote (char-to-string char)))
-                          erc-lurker-ignore-chars ""))
+       (regexp-opt (cl-delete-duplicates
+                    (mapcar #'char-to-string erc-lurker-ignore-chars)))
        "" nick)
     nick))