Fix async handler detection for partial callables

Author: matdev83

src/core/interfaces/command_service.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 
+from asyncio import iscoroutinefunction as asyncio_iscoroutinefunction
 from collections.abc import Awaitable, Callable
-from inspect import iscoroutinefunction
 from typing import Any
 
 from src.core.domain.processed_result import ProcessedResult
@@ -13,11 +13,22 @@
 def _is_async_callable(candidate: Any) -> bool:
     """Return ``True`` when *candidate* is an awaitable callable."""
 
-    if iscoroutinefunction(candidate):  # Fast path for async callables
+    if asyncio_iscoroutinefunction(candidate):  # Handles partials and decorated callables
+        return True
+
+    func_attr = getattr(candidate, "func", None)
+    if func_attr and asyncio_iscoroutinefunction(func_attr):
         return True
 
     call_method = getattr(candidate, "__call__", None)
-    return bool(call_method and iscoroutinefunction(call_method))
+    if not call_method:
+        return False
+
+    if asyncio_iscoroutinefunction(call_method):
+        return True
+
+    bound_function = getattr(call_method, "__func__", None)
+    return bool(bound_function and asyncio_iscoroutinefunction(bound_function))
 
 
 class FunctionCommandService(ICommandService):

tests/unit/core/test_command_service_module.py

@@ -1,3 +1,5 @@
+from functools import partial
+
 import pytest
 from src.core.domain.processed_result import ProcessedResult
 from src.core.interfaces.command_service import ensure_command_service
@@ -48,6 +50,28 @@ async def handler(messages: list[str], session_id: str) -> ProcessedResult:
     assert result.command_results == ["session"]
 
 
+@pytest.mark.asyncio
+async def test_ensure_command_service_accepts_partial_async_callable() -> None:
+    async def handler(
+        messages: list[str], session_id: str, prefix: str
+    ) -> ProcessedResult:
+        return ProcessedResult(
+            modified_messages=[f"{prefix}:{value}" for value in messages],
+            command_executed=bool(messages),
+            command_results=[session_id],
+        )
+
+    partial_handler = partial(handler, prefix="partial")
+
+    validated_service = ensure_command_service(partial_handler)
+
+    result = await validated_service.process_commands(["message"], "session")
+
+    assert result.modified_messages == ["partial:message"]
+    assert result.command_executed is True
+    assert result.command_results == ["session"]
+
+
 def test_ensure_command_service_rejects_sync_callable() -> None:
     def handler(messages: list[str], session_id: str) -> ProcessedResult:
         return ProcessedResult(