Fix erc-server-prevent-duplicates :type

* lisp/erc/erc-backend.el (erc-server-prevent-duplicates): Change
:type to allow a variable-length list of strings.  (Bug#66456)

diff --git a/lisp/erc/erc-backend.el b/lisp/erc/erc-backend.el
index fb10ee31c784fb8763a3b2aca3f98a6b84870ed3..2fb140f57cee380dec050a9cf38889886a7af8e0 100644 (file)
--- a/lisp/erc/erc-backend.el
+++ b/lisp/erc/erc-backend.el
@@ -511,7 +511,7 @@ It should take same arguments as `open-network-stream' does."
   "Either nil or a list of strings.
 Each string is a IRC message type, like PRIVMSG or NOTICE.
 All Message types in that list of subjected to duplicate prevention."
-  :type '(choice (const nil) (list string)))
+  :type '(repeat string))
 
 (defcustom erc-server-duplicate-timeout 60
   "The time allowed in seconds between duplicate messages.