Patch d.py's message convertor to infer channelID from the given context

Discord.py's Message convertor is supposed to infer channelID based on ctx.channel if only a messageID is given. A 'refactor' (linked below) a few weeks before d.py's archival broke this, so that if only a messageID is given to the convertor, it will only find that message if it's in the bot's cache.

Co-authored-by: Hassan Abouelela <[email protected]>

3 files changed, 29 insertions, 0 deletions

diff --git a/bot/__init__.py b/bot/__init__.py
index a1c4466f1..17d99105a 100644
--- a/bot/__init__.py
+++ b/bot/__init__.py
@@ -18,6 +18,11 @@ if os.name == "nt":
 
 monkey_patches.patch_typing()
 
+# This patches any convertors that use PartialMessage, but not the PartialMessageConverter itself
+# as library objects are made by this mapping.
+# https://github.com/Rapptz/discord.py/blob/1a4e73d59932cdbe7bf2c281f25e32529fc7ae1f/discord/ext/commands/converter.py#L984-L1004
+commands.converter.PartialMessageConverter = monkey_patches.FixedPartialMessageConverter
+
 # Monkey-patch discord.py decorators to use the Command subclass which supports root aliases.
 # Must be patched before any cogs are added.
 commands.command = partial(commands.command, cls=monkey_patches.Command)
diff --git a/bot/monkey_patches.py b/bot/monkey_patches.py
index 23482f7c3..b5c0de8d9 100644
--- a/bot/monkey_patches.py
+++ b/bot/monkey_patches.py
@@ -5,6 +5,7 @@ from discord import Forbidden, http
 from discord.ext import commands
 
 from bot.log import get_logger
+from bot.utils.regex import MESSAGE_ID_RE
 
 log = get_logger(__name__)
 
@@ -50,3 +51,25 @@ def patch_typing() -> None:
             pass
 
     http.HTTPClient.send_typing = honeybadger_type
+
+
+class FixedPartialMessageConverter(commands.PartialMessageConverter):
+    """
+    Make the Message converter infer channelID from the given context if only a messageID is given.
+
+    Discord.py's Message converter is supposed to infer channelID based
+    on ctx.channel if only a messageID is given. A refactor commit, linked below,
+    a few weeks before d.py's archival broke this defined behaviour of the converter.
+    Currently, if only a messageID is given to the converter, it will only find that message
+    if it's in the bot's cache.
+
+    https://github.com/Rapptz/discord.py/commit/1a4e73d59932cdbe7bf2c281f25e32529fc7ae1f
+    """
+
+    @staticmethod
+    def _get_id_matches(ctx: commands.Context, argument: str) -> tuple[int, int, int]:
+        """Inserts ctx.channel.id before calling super method if argument is just a messageID."""
+        match = MESSAGE_ID_RE.match(argument)
+        if match:
+            argument = f"{ctx.channel.id}-{match.group('message_id')}"
+        return commands.PartialMessageConverter._get_id_matches(ctx, argument)
diff --git a/bot/utils/regex.py b/bot/utils/regex.py
index d77f5950b..9dc1eba9d 100644
--- a/bot/utils/regex.py
+++ b/bot/utils/regex.py
@@ -12,3 +12,4 @@ INVITE_RE = re.compile(
     r"(?P<invite>[a-zA-Z0-9\-]+)",                # the invite code itself
     flags=re.IGNORECASE
 )
+MESSAGE_ID_RE = re.compile(r'(?P<message_id>[0-9]{15,20})$')