Improve guild member cache fetch logic and fix escaping in message image url search regex

Merge the pydis changes to the bot (modmail-dev#3365)

* Escape hyphen in regex string

Unescaped this was permitting any character between $ (index 36) and _ (index 95), which aren't all valid in urls.

* Get or fetch member when trying to reply

This fixes an issue where the member may not be in the cache

---------

Signed-off-by: Taku <45324516+Taaku18@users.noreply.github.com>
Co-authored-by: Taku <45324516+Taaku18@users.noreply.github.com>
Co-authored-by: Chris Lovering <chris.lovering.95@gmail.com>

(cherry picked from commit 1a3bda8)

Author: sebkuip

bot.py

@@ -662,6 +662,16 @@ async def get_or_fetch_user(self, id: int) -> discord.User:
         """
         return self.get_user(id) or await self.fetch_user(id)
 
+    @staticmethod
+    async def get_or_fetch_member(guild: discord.Guild, member_id: int) -> typing.Optional[discord.Member]:
+        """
+        Attempt to get a member from cache; on failure fetch from the API.
+
+        Returns:
+            The :obj:`discord.Member` or :obj:`None` to indicate the member could not be found.
+        """
+        return guild.get_member(member_id) or await guild.fetch_member(member_id)
+
     async def retrieve_emoji(self) -> typing.Tuple[str, str]:
         sent_emoji = self.config["sent_emoji"]
         blocked_emoji = self.config["blocked_emoji"]

core/thread.py

@@ -835,7 +835,13 @@ async def reply(
         """Returns List[user_dm_msg] and thread_channel_msg"""
         if not message.content and not message.attachments:
             raise MissingRequiredArgument(DummyParam("msg"))
-        if not any(g.get_member(self.id) for g in self.bot.guilds):
+        for guild in self.bot.guilds:
+            try:
+                if await self.bot.get_or_fetch_member(guild, self.id):
+                    break
+            except discord.NotFound:
+                pass
+        else:
             return await message.channel.send(
                 embed=discord.Embed(
                     color=self.bot.error_color,
@@ -1007,7 +1013,7 @@ async def send(
                 attachments.append(attachment)
 
         image_urls = re.findall(
-            r"http[s]?:\/\/(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*(),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+",
+            r"http[s]?:\/\/(?:[a-zA-Z]|[0-9]|[$\-_@.&+]|[!*(),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+",
             message.content,
         )