Change to have parse *always* set serialized_on_wire

betterproto/__init__.py

@@ -741,15 +741,15 @@ class Message(ABC):
         Parse the binary encoded Protobuf into this message instance. This
         returns the instance itself and is therefore assignable and chainable.
         """
+        # Got some data over the wire
+        self._serialized_on_wire = True
+
         for parsed in parse_fields(data):
             field_name = self._betterproto.field_name_by_number.get(parsed.number)
             if not field_name:
                 self._unknown_fields += parsed.raw
                 continue
 
-            # Got some data over the wire
-            self._serialized_on_wire = True
-
             meta = self._betterproto.meta_by_field_name[field_name]
 
             value: Any

betterproto/tests/test_features.py

@@ -39,11 +39,9 @@ def test_has_field():
             2, betterproto.TYPE_STRING, betterproto.TYPE_STRING
         )
 
-    # Unset with empty collections
+    # Is always set from parse, even if all collections are empty
     with_collections_empty = WithCollections().parse(bytes(WithCollections()))
-    assert betterproto.serialized_on_wire(with_collections_empty) == False
-
-    # Set with non-empty collections
+    assert betterproto.serialized_on_wire(with_collections_empty) == True
     with_collections_list = WithCollections().parse(
         bytes(WithCollections(test_list=["a", "b", "c"]))
     )