Generate help embed from function signature

didier/cogs/help.py

@@ -1,3 +1,4 @@
+import re
 from typing import Mapping, Optional
 
 import discord
@@ -63,6 +64,30 @@ class CustomHelpCommand(commands.MinimalHelpCommand):
     def command_not_found(self, string: str, /) -> str:
         return f"Found no command named `{string}`."
 
+    @overrides
+    def get_command_signature(self, command: commands.Command, /) -> str:
+        signature_list = [command.name]
+
+        # Perform renaming for hybrid commands
+        if hasattr(command.callback, "__discord_app_commands_param_rename__"):
+            renames = command.callback.__discord_app_commands_param_rename__
+        else:
+            renames = {}
+
+        sig = command.params
+
+        for name, param in sig.items():
+            name = renames.get(name, name)
+            is_optional = param.default is not param.empty
+
+            # Wrap optional arguments in square brackets
+            if is_optional:
+                name = f"[{name}]"
+
+            signature_list.append(name)
+
+        return " ".join(signature_list)
+
     @overrides
     async def send_bot_help(self, mapping: Mapping[Optional[commands.Cog], list[commands.Command]], /):
         embed = self._help_embed_base("Categories")
@@ -122,10 +147,15 @@ class CustomHelpCommand(commands.MinimalHelpCommand):
 
         This allows re-using this logic for Group commands that can be invoked by themselves.
         """
-        embed.description = command.help
+        # Regex borrowed from https://stackoverflow.com/a/59843498/13568999
+        # Remove single newlines but keep double newlines
+        # This allows short lines in the docstring, but joins them together for the help description
+        embed.description = re.sub(
+            r"([^\S\n]*\n(?:[^\S\n]*\n)+[^\S\n]*)|[^\S\n]*\n[^\S\n]*", lambda x: x.group(1) or " ", command.help
+        )
 
-        if command.usage:
-            embed.add_field(name="Signature", value=f"{command.name} {command.usage}", inline=False)
+        signature = self.get_command_signature(command)
+        embed.add_field(name="Signature", value=signature, inline=False)
 
         if command.aliases:
             embed.add_field(name="Aliases", value=", ".join(command.aliases), inline=False)

didier/cogs/school.py

@@ -27,21 +27,23 @@ class School(commands.Cog):
     def __init__(self, client: Didier):
         self.client = client
 
-    @commands.hybrid_command(name="deadlines", description="Show upcoming deadlines")
+    @commands.hybrid_command(name="deadlines")
     async def deadlines(self, ctx: commands.Context):
-        """Show upcoming deadlines"""
+        """Show upcoming deadlines."""
         async with self.client.postgres_session as session:
             deadlines = await get_deadlines(session)
 
         embed = Deadlines(deadlines).to_embed()
         await ctx.reply(embed=embed, mention_author=False, ephemeral=False)
 
-    @commands.hybrid_command(
-        name="les", description="Show your personalized schedule for a given day.", aliases=["Sched", "Schedule"]
-    )
+    @commands.hybrid_command(name="les", aliases=["sched", "schedule"])
     @app_commands.rename(day_dt="date")
     async def les(self, ctx: commands.Context, day_dt: Optional[app_commands.Transform[date, DateTransformer]] = None):
-        """Show your personalized schedule for a given day."""
+        """Show your personalized schedule for a given day.
+
+        If no day is provided, this defaults to the schedule for the current day. When invoked during a weekend,
+        it will skip forward to the next weekday instead.
+        """
         if day_dt is None:
             day_dt = date.today()
 
@@ -62,14 +64,14 @@ class School(commands.Cog):
 
     @commands.hybrid_command(
         name="menu",
-        description="Show the menu in the Ghent University restaurants.",
-        aliases=["Eten", "Food"],
+        aliases=["eten", "food"],
     )
     @app_commands.rename(day_dt="date")
     async def menu(self, ctx: commands.Context, day_dt: Optional[app_commands.Transform[date, DateTransformer]] = None):
         """Show the menu in the Ghent University restaurants.
 
-        Menus are Dutch, as a lot of dishes have very weird translations
+        If no day is provided, this defaults to the schedule for the current day.
+        Menus are shown in Dutch by default, as a lot of dishes have very weird translations.
         """
         if day_dt is None:
             day_dt = date.today()