From ed89f70f984cf1e314e3215bd253ea4fe7545474 Mon Sep 17 00:00:00 2001
From: jack1142 <6032823+jack1142@users.noreply.github.com>
Date: Thu, 28 May 2020 23:51:53 +0200
Subject: [PATCH] Fix uses of `re.sub()` (#3826)

* Fix uses of `re.sub()` (pt. 1)

* Fix uses of `re.sub()` (pt. 2)

* Fix uses of `re.sub()` (pt. 3)

* Fix uses of `re.sub()` (pt. 4)

* Revert commands.py
---
 redbot/core/commands/context.py      | 2 +-
 redbot/core/core_commands.py         | 4 ++--
 redbot/core/utils/_internal_utils.py | 4 +++-
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/redbot/core/commands/context.py b/redbot/core/commands/context.py
index 5fdef67d0..ca40e3e7f 100644
--- a/redbot/core/commands/context.py
+++ b/redbot/core/commands/context.py
@@ -262,7 +262,7 @@ class Context(DPYContext):
         """str: The command prefix, but a mention prefix is displayed nicer."""
         me = self.me
         pattern = re.compile(rf"<@!?{me.id}>")
-        return pattern.sub(f"@{me.display_name}", self.prefix)
+        return pattern.sub(f"@{me.display_name}".replace("\\", r"\\"), self.prefix)
 
     @property
     def me(self) -> Union[discord.ClientUser, discord.Member]:
diff --git a/redbot/core/core_commands.py b/redbot/core/core_commands.py
index 5697c2fd8..28e389934 100644
--- a/redbot/core/core_commands.py
+++ b/redbot/core/core_commands.py
@@ -1585,7 +1585,7 @@ class Core(commands.Cog, CoreLogic):
             footer += _(" | Server ID: {}").format(guild.id)
 
         prefixes = await ctx.bot.get_valid_prefixes()
-        prefix = re.sub(rf"<@!?{ctx.me.id}>", f"@{ctx.me.name}", prefixes[0])
+        prefix = re.sub(rf"<@!?{ctx.me.id}>", f"@{ctx.me.name}".replace("\\", r"\\"), prefixes[0])
 
         content = _("Use `{}dm {} <text>` to reply to this user").format(prefix, author.id)
 
@@ -1690,7 +1690,7 @@ class Core(commands.Cog, CoreLogic):
             return
 
         prefixes = await ctx.bot.get_valid_prefixes()
-        prefix = re.sub(rf"<@!?{ctx.me.id}>", f"@{ctx.me.name}", prefixes[0])
+        prefix = re.sub(rf"<@!?{ctx.me.id}>", f"@{ctx.me.name}".replace("\\", r"\\"), prefixes[0])
         description = _("Owner of {}").format(ctx.bot.user)
         content = _("You can reply to this message with {}contact").format(prefix)
         if await ctx.embed_requested():
diff --git a/redbot/core/utils/_internal_utils.py b/redbot/core/utils/_internal_utils.py
index 05957a0f9..9e4876efb 100644
--- a/redbot/core/utils/_internal_utils.py
+++ b/redbot/core/utils/_internal_utils.py
@@ -287,7 +287,9 @@ async def send_to_owners_with_prefix_replaced(bot: Red, content: str, **kwargs):
 
     async def preprocessor(bot: Red, destination: discord.abc.Messageable, content: str) -> str:
         prefixes = await bot.get_valid_prefixes(getattr(destination, "guild", None))
-        prefix = re.sub(rf"<@!?{bot.user.id}>", f"@{bot.user.name}", prefixes[0])
+        prefix = re.sub(
+            rf"<@!?{bot.user.id}>", f"@{bot.user.name}".replace("\\", r"\\"), prefixes[0]
+        )
         return content.replace("[p]", prefix)
 
     await send_to_owners_with_preprocessor(bot, content, content_preprocessor=preprocessor)