From 99a45590a48bf5d78696a53f8402f02e246c99de Mon Sep 17 00:00:00 2001
From: CoconutMacaroon <45187468+CoconutMacaroon@users.noreply.github.com>
Date: Sun, 18 Aug 2024 06:06:14 +0000
Subject: [PATCH] Reject multiline chat messages attempting to watch/blacklist
 keywords

---
 chatcommands.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/chatcommands.py b/chatcommands.py
index 39fff25b2c..b18025c2dc 100644
--- a/chatcommands.py
+++ b/chatcommands.py
@@ -389,6 +389,13 @@ def get_normalized_on_list(list_type, extra=''):
     text_before_pattern = ''
     text_after_pattern = ''
 
+    # Block multiline chat messages to avoid corrupting the watchlist/blacklist file(s)
+    # Using -force should not bypass this, as that still results in file corruption
+    if '\n' in pattern:
+        raise CmdException("The watchlist/blacklist cannot be modified using multiline chat messages. If"
+                           " your desired change exceeds the length of a standard chat message, consider"
+                           " using Git to make the change (or ping someone who can).")
+
     other_issues = []
     if '\u202d' in pattern:
         other_issues.append("The pattern contains an invisible U+202D whitespace character.")