Raise ParseError in read_delim

libp2p/protocol_muxer/multiselect_communicator.py

@@ -20,10 +20,10 @@ class MultiselectCommunicator(IMultiselectCommunicator):
         msg_bytes = encode_delim(msg_str.encode())
         try:
             await self.read_writer.write(msg_bytes)
-        except IOException:
+        except IOException as error:
             raise MultiselectCommunicatorError(
                 "fail to write to multiselect communicator"
-            )
+            ) from error
 
     async def read(self) -> str:
         """
@@ -32,8 +32,8 @@ class MultiselectCommunicator(IMultiselectCommunicator):
         try:
             data = await read_delim(self.read_writer)
         # `IOException` includes `IncompleteReadError` and `StreamError`
-        except (ParseError, IOException, ValueError):
+        except (ParseError, IOException) as error:
             raise MultiselectCommunicatorError(
                 "fail to read from multiselect communicator"
-            )
+            ) from error
         return data.decode()

libp2p/utils.py

@@ -73,9 +73,8 @@ def encode_delim(msg: bytes) -> bytes:
 
 async def read_delim(reader: Reader) -> bytes:
     msg_bytes = await read_varint_prefixed_bytes(reader)
-    # TODO: Investigate if it is possible to have empty `msg_bytes`
-    if len(msg_bytes) != 0 and msg_bytes[-1:] != b"\n":
-        raise ValueError(f'msg_bytes is not delimited by b"\\n": msg_bytes={msg_bytes}')
+    if len(msg_bytes) == 0 or msg_bytes[-1:] != b"\n":
+        raise ParseError(f'msg_bytes is not delimited by b"\\n": msg_bytes={msg_bytes}')
     return msg_bytes[:-1]
 
 

tests/interop/test_bindings.py

@@ -22,6 +22,5 @@ async def test_connect(hosts, p2pds):
     assert len(host.get_network().connections) == 1
     # Test: `disconnect` from Go
     await p2pd.control.disconnect(host.get_id())
-    # FIXME: Failed to handle disconnect
     await asyncio.sleep(0.01)
     assert len(host.get_network().connections) == 0