discord.py最新版本加载Cog出现TypeError(NoneType)错误如何解决？

错误信息 #

File "C:\Users\MyUsername\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\discord\ext\commands\bot.py", line 946, in _load_from_module_spec
    await setup(self)
TypeError: object NoneType can't be used in 'await' expression

相关代码 #

main.py #

import discord
import os
from discord.ext import commands

# Create bot
client = commands.Bot(command_prefix=">", intents=discord.Intents.all())


# Load commands
@client.command()
async def load(ctx, extension):
    await client.load_extension(f"Cogs.{extension}")


# Unload commands
@client.command()
async def unload(ctx, extension):
    await client.unload_extension(f"Cogs.{extension}")


# On start
@client.event
async def on_ready():
    # Import all commands on start
    for filename in os.listdir("./Cogs"):
        if filename.endswith(".py"):
            await client.load_extension(f"Cogs.{filename[:-3]}")

# 注：Client.run()已省略，实际位于代码末尾

Ping.py（Cog文件） #

import discord
from discord.ext import commands
import time


class Ping(commands.Cog):
    def __init__(self, client):
        self.client = client

    @commands.Cog.listener()
    async def on_ready(self):
        print("Bot is online")
        await self.client.change_presence(
            status=discord.Status.online,
            activity=discord.Game('SuperBot, >help for help')
        )

    @commands.command()
    async def ping(self, ctx):
        embed = discord.Embed(
            title="Pong!",
            description=f"I'm up! The bot latency is {self.client.latency}",
            color=discord.Colour.random()
        )
        embed.set_footer(
            text=time.strftime("%a : %H : %M")
        )
        await ctx.channel.send(embed=embed)


def setup(client):
    client.add_cog(Ping(client))

问题描述 #

使用discord.py最新版本开发Discord机器人，已配置intents，启动时始终报上述错误。尝试将加载Cog的代码移出on_ready函数，问题依旧。

解决方案 #

• 核心修复：修改Cog的setup函数为异步
  discord.py v2.0+版本要求Cog的setup函数必须是异步函数，当前同步的setup返回None，框架执行await setup(self)时就会触发类型错误。修改Ping.py中的setup函数：

  async def setup(client):
      await client.add_cog(Ping(client))
  

• 优化加载逻辑（可选）
  推荐使用setup_hook替代on_ready加载扩展，因为on_ready可能在bot重连时多次触发，而setup_hook仅在启动时执行一次，避免重复加载Cog。修改main.py中的启动逻辑：

  @client.event
  async def setup_hook():
      # Import all commands on start
      for filename in os.listdir("./Cogs"):
          if filename.endswith(".py"):
              await client.load_extension(f"Cogs.{filename[:-3]}")
  

内容的提问来源于stack exchange，提问作者Help pls