Fix nested Annotated calls not resolving

tests/test_annotated_annotation.py

@@ -0,0 +1,61 @@
+"""
+The MIT License (MIT)
+
+Copyright (c) 2015-present Rapptz
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+"""
+
+from __future__ import annotations
+from typing import Optional
+from typing_extensions import Annotated
+
+import discord
+from discord import app_commands
+from discord.ext import commands
+
+import pytest
+
+def test_annotated_annotation():
+    # can't exactly test if the parameter is the same, so just test if it raises something
+    @app_commands.command()
+    async def foo(interaction: discord.Interaction, param: Annotated[float, Optional[int]]):
+        pass
+
+
+    def to_hex(arg: str) -> int:
+        return int(arg, 16)
+
+    class Flag(commands.FlagConverter):
+        thing: Annotated[int, to_hex]
+
+    assert Flag.get_flags()['thing'].annotation == to_hex
+
+    @commands.command()
+    async def bar(ctx: commands.Context, param: Annotated[float, Optional[int]]):
+        pass
+
+    assert bar.clean_params['param'].annotation == Optional[int]
+
+    @commands.command()
+    async def nested(ctx: commands.Context, param: Optional[Annotated[str, int]]):
+        pass
+
+    assert nested.clean_params['param'].annotation == Optional[int]
+