slash_command_test.py

import discord

import inspect

def _get_options(callback):
    sig = inspect.signature(callback)
    options = []
    
    types = {
        str: 3,
        int: 4,
        bool: 5,
        discord.User: 6,
        discord.abc.GuildChannel: 7,
        discord.Role: 8,
        float: 10
    }
    
    iterator = iter(sig.parameters.items())
    next(iterator)

    for name, param in iterator:
        if not isinstance(param.annotation, Option):
            raise TypeError(f'annotation must be `Option` not {param.annotation!r}')
        option = {}
        
        option['type'] = types[param.annotation.type]
        option['name'] = name
        
        # I couldn't think of a way to do this properly...
        option['description'] = param.annotation.description
        
        option['required'] = param.default == inspect._empty
        
        options.append(option)
    
    return options if options else None

class Command:
    def __init__(self, callback, options):
        self.callback = callback
        self.options = options


class Option:
    def __init__(self, type, description):
        self.type = type
        self.description = description

class Client(discord.Client):
    def __init__(self, *args, **kwargs):
        self.commands = {}
        super().__init__(*args, **kwargs)

    def _resolve_options(self, interaction, data):
        args = []
        for num, option in enumerate(data['options']):
            if option['type'] in (3, 4, 5, 10):
                args.append(option['value'])
                continue

            elif option['type'] == 6:
                user_data = data['resolved']['users'][option['value']]

                try:
                    member_data = data['resolved']['members'][option['value']]
                except KeyError:
                    user = discord.User(state=self._get_state(), data=user_data)
                else:
                    member_data['user'] = user_data
                    user = discord.Member(data=member_data, guild=interaction.guild, state=self._get_state())
                finally:
                    args.append(user)

            elif option['type'] == 7:
                args.append(interaction.guild.get_channel(int(option['value'])))

            elif option['type'] == 8:
                args.append(interaction.guild.get_role(int(option['value'])))
        return args
        
    async def on_interaction(self, interaction):
        data = interaction.data
        if data['type'] == 1:

            command = self.commands[data['id']]

            if 'options' in data:
                args = self._resolve_options(interaction, data)

                await command.callback(interaction, *args)
            else:
                await command.callback(interaction)

    def command(self, *, name, description, guild_id=None):
        def inner(func):
            options = _get_options(func)
            command = Command(func, options)


            async def task():
                await self.wait_until_ready()
            
                payload = {
                    'name': name,
                    'description': description
                }
                if command.options is not None:
                    payload['options'] = command.options
                
                if guild_id is not None:
                    resp = await self.http.upsert_guild_command(self.user.id, guild_id, payload)
                else:
                    resp = await self.http.upsert_global_command(self.user.id, payload)
                
                command.id = resp['id']

                self.commands[resp['id']] = command
               
            self.loop.create_task(task())
                
            return command
        return inner
       

client = Client()

@client.command(name='userinfo', description='Display information on a user.', guild_id=862374318913355776)
async def test(interaction, user: Option(discord.User, 'The user you want to display information on.')=None):

    user = user or interaction.user

    e = discord.Embed()
    roles = [role.name.replace('@', '@\u200b') for role in getattr(user, 'roles', [])]
    e.set_author(name=str(user))

    def format_date(dt):
        if dt is None:
            return 'N/A'
        return f'{discord.utils.format_dt(dt, "F")} ({discord.utils.format_dt(dt, "R")})'

    e.add_field(name='ID', value=user.id, inline=False)
    e.add_field(name='Joined', value=format_date(getattr(user, 'joined_at', None)), inline=False)
    e.add_field(name='Created', value=format_date(user.created_at), inline=False)

    voice = getattr(user, 'voice', None)
    if voice is not None:
        vc = voice.channel
        other_people = len(vc.members) - 1
        voice = f'{vc.name} with {other_people} others' if other_people else f'{vc.name} by themselves'
        e.add_field(name='Voice', value=voice, inline=False)

    if roles:
        e.add_field(name='Roles', value=', '.join(roles) if len(roles) < 10 else f'{len(roles)} roles', inline=False)

    colour = user.colour
    if colour.value:
        e.colour = colour

    e.set_thumbnail(url=user.display_avatar.url)
    await interaction.response.send_message(embed=e, ephemeral=True)
    
client.run(token)