From c3f39fc93be647140de2f3e28ee1ce2c73114917 Mon Sep 17 00:00:00 2001
From: Valentin Lorentz <progval+git@progval.net>
Date: Wed, 26 May 2021 17:50:11 +0200
Subject: [PATCH] callbacks, Misc, Relay: Fix when the message prefix is just a
 nick

<user> and <host> are optional in https://datatracker.ietf.org/doc/html/rfc1459#section-2.3.1

Closes GH-1451.
---
 plugins/Misc/plugin.py  | 5 ++++-
 plugins/Relay/plugin.py | 4 ++--
 src/callbacks.py        | 5 +++--
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/plugins/Misc/plugin.py b/plugins/Misc/plugin.py
index 7b934396d..e4e9395ae 100644
--- a/plugins/Misc/plugin.py
+++ b/plugins/Misc/plugin.py
@@ -381,7 +381,10 @@ class Misc(callbacks.Plugin):
         If <nick> is given, it takes the continuation of the last command from
         <nick> instead of the person sending this message.
         """
-        userHostmask = msg.prefix.split('!', 1)[1]
+        if '!' in msg.prefix and '@' in msg.prefix:
+            userHostmask = msg.prefix.split('!', 1)[1]
+        else:
+            userHostmask = msg.nick
         if nick:
             try:
                 (private, L) = irc._mores[nick]
diff --git a/plugins/Relay/plugin.py b/plugins/Relay/plugin.py
index 1a2b184ba..1b533783d 100644
--- a/plugins/Relay/plugin.py
+++ b/plugins/Relay/plugin.py
@@ -341,7 +341,7 @@ class Relay(callbacks.Plugin):
         if channel not in self.registryValue('channels'):
             return
         network = self._getIrcName(irc)
-        if self.registryValue('hostmasks', channel):
+        if self.registryValue('hostmasks', channel) and '!' in msg.prefix:
             hostmask = format(' (%s)', msg.prefix.split('!')[1])
         else:
             hostmask = ''
@@ -355,7 +355,7 @@ class Relay(callbacks.Plugin):
         if channel not in self.registryValue('channels'):
             return
         network = self._getIrcName(irc)
-        if self.registryValue('hostmasks', channel):
+        if self.registryValue('hostmasks', channel) and '!' in msg.prefix:
             hostmask = format(' (%s)', msg.prefix.split('!')[1])
         else:
             hostmask = ''
diff --git a/src/callbacks.py b/src/callbacks.py
index 8942b0997..436029a25 100644
--- a/src/callbacks.py
+++ b/src/callbacks.py
@@ -883,8 +883,9 @@ class ReplyIrcProxy(RichReplyMethods):
                     prefix = state.nickToHostmask(target)
                 except KeyError:
                     pass # We'll leave it as it is.
-            mask = prefix.split('!', 1)[1]
-            self._mores[mask] = msgs
+            if '!' in prefix and '@' in prefix:
+                mask = prefix.split('!', 1)[1]
+                self._mores[mask] = msgs
             public = bool(self.msg.channel)
             private = kwargs.get('private', False) or not public
             self._mores[msg.nick] = (private, msgs)