Switch the order of ERC's '/whois' arguments sent to the server

* lisp/erc/erc.el (erc-cmd-WHOIS): Switch the order of 'server' and
'user' arguments sent to the server.  Per RFC 1459 and RFC 2812, the
optional 'server' argument command comes before the 'user' argument,
not after.  While at it, update the doc string to explain why one may
want to specify the 'server' argument.
* etc/NEWS: Announce the change.

2 files changed, 11 insertions, 3 deletions

diff --git a/etc/NEWS b/etc/NEWS
index 6d039bac4a8..bf942cb1872 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -2853,6 +2853,11 @@ The new '/opme' convenience command asks ChanServ to set the operator
 status for the current nick in the current channel, and '/deopme'
 unsets it.
 
+---
+*** Fix the order of '/whois' arguments sent to the server.
+Per RFC 1459 and RFC 2812, when given, the optional 'server' argument
+for the WHOIS command must come before the 'user' argument, not after.
+
 ** xwidget-webkit mode
 
 ---
diff --git a/lisp/erc/erc.el b/lisp/erc/erc.el
index ac0c08bd3a2..7fa2d37c9f2 100644
--- a/lisp/erc/erc.el
+++ b/lisp/erc/erc.el
@@ -3301,10 +3301,13 @@ a script after exceeding the flood threshold."
 (defun erc-cmd-WHOIS (user &optional server)
   "Display whois information for USER.
 
-If SERVER is non-nil, use that, rather than the current server."
-  ;; FIXME: is the above docstring correct?  -- Lawrence 2004-01-08
+If SERVER is non-nil, use that, rather than the current server.
+This is useful for getting the time USER has been idle for, if
+USER is on a different server of the network than the current
+user, since only the server the user is connected to knows this
+information."
   (let ((send (if server
-                  (format "WHOIS %s %s" user server)
+                  (format "WHOIS %s %s" server user)
                 (format "WHOIS %s" user))))
     (erc-log (format "cmd: %s" send))
     (erc-server-send send)