From 12c1f6d764917886bf3bb738b61e454dbc2c2a4c Mon Sep 17 00:00:00 2001
From: synodriver <diguohuangjiajinweijun@gmail.com>
Date: Thu, 9 Sep 2021 23:02:05 +0800
Subject: [PATCH] :bug: fix USER bug

---
 nonebot/permission.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/nonebot/permission.py b/nonebot/permission.py
index 68c34f82..ac99504b 100644
--- a/nonebot/permission.py
+++ b/nonebot/permission.py
@@ -141,8 +141,8 @@ def USER(*user: str, perm: Optional[Permission] = None):
     """
 
     async def _user(bot: "Bot", event: "Event") -> bool:
-        return bool(event.get_session_id() in user and perm and
-                    await perm(bot, event))
+        return bool(event.get_session_id() in user and (perm is None or
+                    await perm(bot, event)))
 
     return Permission(_user)