From e8ffa63b7841c1348c1d282b9b56680502f2c397 Mon Sep 17 00:00:00 2001
From: Ju4tCode <42488585+yanyongyu@users.noreply.github.com>
Date: Tue, 29 Nov 2022 12:00:09 +0800
Subject: [PATCH] :bug: fix argument parser message (#1426)

---
 nonebot/rule.py    | 14 +++++++++++---
 tests/test_rule.py |  1 +
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/nonebot/rule.py b/nonebot/rule.py
index a9b1cca3..a7b4dd08 100644
--- a/nonebot/rule.py
+++ b/nonebot/rule.py
@@ -12,6 +12,7 @@ import re
 import shlex
 from argparse import Action
 from argparse import ArgumentError
+from contextvars import ContextVar
 from itertools import chain, product
 from argparse import Namespace as Namespace
 from argparse import ArgumentParser as ArgParser
@@ -73,6 +74,8 @@ TRIE_VALUE = NamedTuple(
     "TRIE_VALUE", [("command_start", str), ("command", Tuple[str, ...])]
 )
 
+parser_message: ContextVar[str] = ContextVar("parser_message")
+
 
 class TrieRule:
     prefix: CharTrie = CharTrie()
@@ -446,13 +449,15 @@ class ArgumentParser(ArgParser):
         )
 
     def _print_message(self, message: str, file: Optional[IO[str]] = None):
-        if message:
-            setattr(self, "_message", getattr(self, "_message", "") + message)
+        if (msg := parser_message.get(None)) is not None:
+            parser_message.set(msg + message)
+        else:
+            super()._print_message(message, file)
 
     def exit(self, status: int = 0, message: Optional[str] = None):
         if message:
             self._print_message(message)
-        raise ParserExit(status=status, message=getattr(self, "_message", None))
+        raise ParserExit(status=status, message=parser_message.get(None))
 
 
 class ShellCommandRule:
@@ -499,6 +504,7 @@ class ShellCommandRule:
         )
 
         if self.parser:
+            t = parser_message.set("")
             try:
                 args = self.parser.parse_args(state[SHELL_ARGV])
                 state[SHELL_ARGS] = args
@@ -506,6 +512,8 @@ class ShellCommandRule:
                 state[SHELL_ARGS] = ParserExit(status=2, message=str(e))
             except ParserExit as e:
                 state[SHELL_ARGS] = e
+            finally:
+                parser_message.reset(t)
         return True
 
 
diff --git a/tests/test_rule.py b/tests/test_rule.py
index d815b91c..1a7d4aab 100644
--- a/tests/test_rule.py
+++ b/tests/test_rule.py
@@ -296,6 +296,7 @@ async def test_shell_command(app: App):
     assert state[SHELL_ARGV] == []
     assert isinstance(state[SHELL_ARGS], ParserExit)
     assert state[SHELL_ARGS].status != 0
+    assert state[SHELL_ARGS].message.startswith(parser.format_usage() + "test: error:")
 
     test_message_parser = shell_command(CMD, parser=parser)
     dependent = list(test_message_parser.checkers)[0]