Added DbusSignalAsync.catch method, identical to __aiter__

docs/asyncio_api.rst

@@ -402,15 +402,18 @@ Decorators
 
     Signals have following methods:
 
-    .. py:method:: __aiter__()
+    .. py:method:: catch()
 
-        Signal can be used as an async generator for loop:
-        ``async for x in something.some_signal:``
+        Catch D-Bus signals using the async generator for loop:
+        ``async for x in something.some_signal.catch():``
 
         This is main way to await for new events.
 
         Both remote and local objects operate the same way.
 
+        Signal objects can also be async iterated directly:
+        ``async for x in something.some_signal``
+
     .. py:method:: emit(args)
 
         Emit a new signal with *args* data.

src/sdbus/dbus_proxy_async_signal.py

@@ -61,13 +61,20 @@ def __get__(self,
 class DbusSignalBinded(Generic[T], DbusBindedAsync):
     def __init__(self,
                  dbus_signal: DbusSignalAsync[T],
-                 interface: DbusInterfaceBaseAsync):
+                 interface: Optional[DbusInterfaceBaseAsync]):
         self.dbus_signal = dbus_signal
-        self.interface_ref = weak_ref(interface)
+        if interface is not None:
+            self.interface_ref: Optional[weak_ref[DbusInterfaceBaseAsync]] \
+                = weak_ref(interface)
+        else:
+            self.interface_ref = None
 
         self.__doc__ = dbus_signal.__doc__
 
     async def _get_dbus_queue(self) -> Queue[SdBusMessage]:
+        assert self.interface_ref is not None, (
+            "Called method from class?"
+        )
         interface = self.interface_ref()
         assert interface is not None
 
@@ -87,12 +94,18 @@ async def _get_dbus_queue(self) -> Queue[SdBusMessage]:
     def _cleanup_local_queue(
             self,
             queue_ref: weak_ref[Queue[T]]) -> None:
+        assert self.interface_ref is not None, (
+            "Called method from class?"
+        )
         interface = self.interface_ref()
         assert interface is not None
 
         interface._local_signal_queues[self.dbus_signal].remove(queue_ref)
 
     def _get_local_queue(self) -> Queue[T]:
+        assert self.interface_ref is not None, (
+            "Called method from class?"
+        )
         interface = self.interface_ref()
         assert interface is not None
 
@@ -110,8 +123,10 @@ def _get_local_queue(self) -> Queue[T]:
 
         return new_queue
 
-    async def __aiter__(self) -> AsyncGenerator[T, None]:
-
+    async def catch(self) -> AsyncGenerator[T, None]:
+        assert self.interface_ref is not None, (
+            "Called method from class?"
+        )
         interface = self.interface_ref()
         assert interface is not None
 
@@ -128,7 +143,12 @@ async def __aiter__(self) -> AsyncGenerator[T, None]:
                 next_data = await data_queue.get()
                 yield next_data
 
+    __aiter__ = catch
+
     def _emit_message(self, args: T) -> None:
+        assert self.interface_ref is not None, (
+            "Called method from class?"
+        )
         interface = self.interface_ref()
         assert interface is not None
 
@@ -155,6 +175,9 @@ def _emit_message(self, args: T) -> None:
         signal_message.send()
 
     def emit(self, args: T) -> None:
+        assert self.interface_ref is not None, (
+            "Called method from class?"
+        )
         interface = self.interface_ref()
         assert interface is not None
 

test/test_sd_bus_async.py

@@ -465,7 +465,7 @@ async def test_emits_properties_changed(self) -> None:
         loop = get_running_loop()
 
         async def catch_property_emit_connection() -> str:
-            async for x in test_object_connection.properties_changed:
+            async for x in test_object_connection.properties_changed.catch():
                 for v in x[1].values():
                     probably_str = v[1]
                     if isinstance(probably_str, str):
@@ -475,7 +475,7 @@ async def catch_property_emit_connection() -> str:
             raise ValueError
 
         async def catch_property_emit_local() -> str:
-            async for x in test_object.properties_changed:
+            async for x in test_object.properties_changed.catch():
                 for v in x[1].values():
                     probably_str = v[1]
                     if isinstance(probably_str, str):