pw_rpc: Require an output function for channels

- The code already assumed the output function was not None, so require
  an output function.
- Remove type: ignore comments that were no longer necessary.

Change-Id: I9a43d3c49f401c82c7a4cdb47a1798866853eccd
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/227855
Pigweed-Auto-Submit: Wyatt Hepler <[email protected]>
Commit-Queue: Wyatt Hepler <[email protected]>
Lint: Lint 🤖 <[email protected]>
Reviewed-by: Armando Montanez <[email protected]>

pw_rpc/py/pw_rpc/client.py

@@ -123,15 +123,13 @@ def send_request(
         previous = self.open(rpc, context, override_pending)
         packet = packets.encode_request(rpc, request)
 
-        # TODO(hepler): Remove `type: ignore[misc]` below when
-        #     https://github.com/python/mypy/issues/10711 is fixed.
         if ignore_errors:
             try:
-                rpc.channel.output(packet)  # type: ignore[misc]
+                rpc.channel.output(packet)
             except Exception as err:  # pylint: disable=broad-except
                 _LOG.debug('Ignoring exception when starting RPC: %s', err)
         else:
-            rpc.channel.output(packet)  # type: ignore[misc]
+            rpc.channel.output(packet)
 
         return previous
 
@@ -168,19 +166,15 @@ def send_client_stream(self, rpc: PendingRpc, message: Message) -> None:
         if rpc not in self._pending:
             raise Error(f'Attempt to send client stream for inactive RPC {rpc}')
 
-        rpc.channel.output(  # type: ignore
-            packets.encode_client_stream(rpc, message)
-        )
+        rpc.channel.output(packets.encode_client_stream(rpc, message))
 
     def send_client_stream_end(self, rpc: PendingRpc) -> None:
         if rpc not in self._pending:
             raise Error(
                 f'Attempt to send client stream end for inactive RPC {rpc}'
             )
 
-        rpc.channel.output(  # type: ignore
-            packets.encode_client_stream_end(rpc)
-        )
+        rpc.channel.output(packets.encode_client_stream_end(rpc))
 
     def cancel(self, rpc: PendingRpc) -> bytes:
         """Cancels the RPC.
@@ -204,7 +198,7 @@ def send_cancel(self, rpc: PendingRpc) -> bool:
             return False
 
         if packet:
-            rpc.channel.output(packet)  # type: ignore
+            rpc.channel.output(packet)
 
         return True
 
@@ -669,6 +663,4 @@ def _send_client_error(
 ) -> None:
     # Never send responses to SERVER_ERRORs.
     if packet.type != PacketType.SERVER_ERROR:
-        client.channel.output(  # type: ignore
-            packets.encode_client_error(packet, error)
-        )
+        client.channel.output(packets.encode_client_error(packet, error))

pw_rpc/py/pw_rpc/descriptors.py

@@ -44,7 +44,7 @@
 @dataclass(frozen=True)
 class Channel:
     id: int
-    output: Callable[[bytes], Any] | None
+    output: Callable[[bytes], Any]
 
     def __repr__(self) -> str:
         return f'Channel({self.id})'

pw_rpc/py/tests/client_test.py

@@ -90,7 +90,7 @@ def create_protos() -> Any:
 
 def create_client(
     proto_modules: Any,
-    first_channel_output_fn: Callable[[bytes], Any] | None = None,
+    first_channel_output_fn: Callable[[bytes], Any] = lambda _: None,
 ) -> client.Client:
     return client.Client.from_modules(
         callback_client.Impl(),