Source: Create converter for source object converting

1 files changed, 31 insertions, 2 deletions

diff --git a/bot/cogs/source.py b/bot/cogs/source.py
index 4897a16e3..76f75f83b 100644
--- a/bot/cogs/source.py
+++ b/bot/cogs/source.py
@@ -1,10 +1,39 @@
-from discord.ext.commands import Cog
+from typing import Union
+
+from discord.ext.commands import BadArgument, Cog, Context, Converter, Command, HelpCommand
 
 from bot.bot import Bot
 
 
+class SourceConverted(Converter):
+    """Convert argument to help command, command or Cog."""
+
+    async def convert(self, ctx: Context, argument: str) -> Union[HelpCommand, Command, Cog]:
+        """
+        Convert argument into source object.
+
+        Order how arguments is checked:
+        1. When argument is `help`, return bot help command
+        2. When argument is valid command, return this command
+        3. When argument is valid Cog, return this Cog
+        4. Otherwise raise `BadArgument` error
+        """
+        if argument.lower() == "help":
+            return ctx.bot.help_command
+
+        command = ctx.bot.get_command(argument)
+        if command:
+            return command
+
+        cog = ctx.bot.get_cog(argument)
+        if cog:
+            return cog
+
+        raise BadArgument(f"Unable to convert `{argument}` to help command, command or cog.")
+
+
 class Source(Cog):
-    """Cog of Python Discord project source information."""
+    """Cog of Python Discord projects source information."""
 
     def __init__(self, bot: Bot):
         self.bot = bot