Fix is_coroutine_callable for a partial over an async callable object

releasenotes/notes/fix-is-coroutine-callable-partial-async-object-3c1f9a2b7e4d6058.yaml

@@ -0,0 +1,7 @@
+---
+fixes:
+  - |
+    Detect a ``functools.partial`` wrapping a callable object whose
+    ``__call__`` is asynchronous as a coroutine callable. Previously such a
+    partial was misrouted to the synchronous retry path, which returned an
+    un-awaited coroutine instead of retrying the awaited call.

tenacity/_utils.py

@@ -92,8 +92,12 @@ def is_coroutine_callable(call: typing.Callable[..., typing.Any]) -> bool:
         return False
     if inspect.iscoroutinefunction(call):
         return True
-    partial_call = isinstance(call, functools.partial) and call.func
-    dunder_call = partial_call or getattr(call, "__call__", None)  # noqa: B004
+    if isinstance(call, functools.partial):
+        # Recurse into the wrapped target so a partial over a callable *object*
+        # with an async ``__call__`` (not just a plain coroutine function) is
+        # still detected as a coroutine callable.
+        return is_coroutine_callable(call.func)
+    dunder_call = getattr(call, "__call__", None)  # noqa: B004
     return inspect.iscoroutinefunction(dunder_call)
 
 

tests/test_utils.py

@@ -24,6 +24,8 @@ def __call__(self) -> None:
     partial_sync_func = functools.partial(sync_func)
     partial_async_class = functools.partial(AsyncClass().__call__)
     partial_sync_class = functools.partial(SyncClass().__call__)
+    partial_async_instance = functools.partial(AsyncClass())
+    partial_sync_instance = functools.partial(SyncClass())
     partial_lambda_fn = functools.partial(lambda_fn)
 
     assert _utils.is_coroutine_callable(async_func) is True
@@ -38,6 +40,8 @@ def __call__(self) -> None:
     assert _utils.is_coroutine_callable(partial_sync_func) is False
     assert _utils.is_coroutine_callable(partial_async_class) is True
     assert _utils.is_coroutine_callable(partial_sync_class) is False
+    assert _utils.is_coroutine_callable(partial_async_instance) is True
+    assert _utils.is_coroutine_callable(partial_sync_instance) is False
     assert _utils.is_coroutine_callable(partial_lambda_fn) is False