Support specifying top-level aliases in the command and group decorator

bot/__init__.py

@@ -2,8 +2,12 @@
 
 import os
 import typing
+from functools import partial, partialmethod
 
 import loguru
+from bot.command import Command
+from bot.group import Group
+from discord.ext import commands
 from loguru import logger
 
 from .constants import LOG_FILE
@@ -24,3 +28,12 @@ def should_rotate(message: loguru.Message, file: typing.TextIO) -> bool:
 
 logger.add(LOG_FILE, rotation=should_rotate)
 logger.info("Logging Process Started")
+
+
+# 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=Command)
+commands.GroupMixin.command = partialmethod(commands.GroupMixin.command, cls=Command)
+
+commands.group = partial(commands.group, cls=Group)
+commands.GroupMixin.group = partialmethod(commands.GroupMixin.group, cls=Group)

bot/bot.py

@@ -1,4 +1,5 @@
 import os
+from typing import Optional
 
 from aiohttp import ClientSession
 from discord import Embed
@@ -55,3 +56,45 @@ async def close(self) -> None:
 
         if self.http_session:
             await self.http_session.close()
+
+    def add_command(self, command: commands.Command) -> None:
+        """Add `command` as normal and then add its root aliases to the bot."""
+        super().add_command(command)
+        self._add_root_aliases(command)
+
+    def remove_command(self, name: str) -> Optional[commands.Command]:
+        """
+        Remove a command/alias as normal and then remove its root aliases from the bot.
+
+        Individual root aliases cannot be removed by this function.
+        To remove them, either remove the entire command or manually edit `bot.all_commands`.
+        """
+        command = super().remove_command(name)
+        if command is None:
+            # Even if it's a root alias, there's no way to get the Bot instance to remove the alias.
+            return
+
+        self._remove_root_aliases(command)
+        return command
+
+    def _add_root_aliases(self, command: commands.Command) -> None:
+        """Recursively add root aliases for `command` and any of its subcommands."""
+        if isinstance(command, commands.Group):
+            for subcommand in command.commands:
+                self._add_root_aliases(subcommand)
+
+        for alias in getattr(command, "root_aliases", ()):
+            if alias in self.all_commands:
+                # If alias matches any of the commands in the bot, then raise CommandRegistrationError
+                raise commands.CommandRegistrationError(alias, alias_conflict=True)
+
+            self.all_commands[alias] = command
+
+    def _remove_root_aliases(self, command: commands.Command) -> None:
+        """Recursively remove root aliases for `command` and any of its subcommands."""
+        if isinstance(command, commands.Group):
+            for subcommand in command.commands:
+                self._remove_root_aliases(subcommand)
+
+        for alias in getattr(command, "root_aliases", ()):
+            self.all_commands.pop(alias, None)

bot/command.py

@@ -0,0 +1,23 @@
+from discord.ext import commands
+
+
+class Command(commands.Command):
+    """
+    A `discord.ext.commands.Command` subclass which supports root aliases.
+
+    A `root_aliases` keyword argument is added, which is a sequence of alias names that will act as
+    top-level commands rather than being aliases of the command's group.
+
+    Example:
+        `!gh issue 72` can also be called as `!issue 72`.
+        `!gh src eval` can also be called as `!src eval`.
+    """
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.root_aliases = kwargs.get("root_aliases", [])
+
+        if not isinstance(self.root_aliases, (list, tuple)):
+            raise TypeError(
+                "Root aliases must be of type list or tuple, containing strings."
+            )

bot/exts/github/github.py

@@ -1,5 +1,6 @@
 import typing
 
+from bot.bot import Bot
 from bot.constants import BOT_REPO_URL
 from discord import Embed
 from discord.ext import commands
@@ -18,15 +19,15 @@ class Github(commands.Cog):
         └ source        Displays information about the bot's source code.
     """
 
-    def __init__(self, bot: commands.Bot) -> None:
+    def __init__(self, bot: Bot) -> None:
         self.bot = bot
 
     @commands.group(name="github", aliases=("gh",), invoke_without_command=True)
     async def github_group(self, ctx: commands.Context) -> None:
         """Commands for Github."""
         await ctx.send_help(ctx.command)
 
-    @github_group.command(name="profile")
+    @github_group.command(name="profile", root_aliases=("profile",))
     @commands.cooldown(1, 10, BucketType.user)
     async def profile(self, ctx: commands.Context, username: str) -> None:
         """
@@ -39,7 +40,7 @@ async def profile(self, ctx: commands.Context, username: str) -> None:
 
         await ctx.send(embed=embed)
 
-    @github_group.command(name="issue", aliases=("pr",))
+    @github_group.command(name="issue", aliases=("pr",), root_aliases=("pr", "issue"))
     async def issue(
         self,
         ctx: commands.Context,
@@ -63,7 +64,11 @@ async def issue(
 
         await ctx.send(embed=embed)
 
-    @github_group.command(name="source", aliases=("src", "inspect"))
+    @github_group.command(
+        name="source",
+        aliases=("src", "inspect"),
+        root_aliases=("src", "inspect", "source"),
+    )
     async def source_command(
         self, ctx: commands.Context, *, source_item: typing.Optional[str] = None
     ) -> None:
@@ -86,6 +91,6 @@ async def source_command(
         await ctx.send(embed=embed)
 
 
-def setup(bot: commands.Bot) -> None:
+def setup(bot: Bot) -> None:
     """Load the Github cog."""
     bot.add_cog(Github(bot))

bot/group.py

@@ -0,0 +1,23 @@
+from discord.ext import commands
+
+
+class Group(commands.Group):
+    """
+    A `discord.ext.commands.Group` subclass which supports root aliases.
+
+    A `root_aliases` keyword argument is added, which is a sequence of alias names that will act as
+    top-level groups rather than being aliases of the group's group
+
+    Example:
+        `!cmd gh issue 72` can also be called as `!gh issue 72`.
+        `!cmd src eval` can also be called as `!gh src eval`.
+    """
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.root_aliases = kwargs.get("root_aliases", [])
+
+        if not isinstance(self.root_aliases, (list, tuple)):
+            raise TypeError(
+                "Root aliases must be of type list or tuple, containing strings."
+            )