refactor proto_fill_from_dict & proto_to_dict; #56

* added tests for both function
* both function now support py3 iterators types like map, range, filter
* proto_fill_from_dict will correctly overwrite lists when clear=False

protobufs/test_messages.proto

@@ -0,0 +1,25 @@
+syntax = "proto2";
+
+message ComplexProtoMessage {
+	message InnerMessage {
+        optional string text = 1;
+        repeated uint32 numbers = 2;
+	}
+	message InnerBuffer {
+        message Flags {
+            optional bool flag = 1;
+        }
+
+		optional bytes data = 1;
+        repeated .ComplexProtoMessage.InnerBuffer.Flags flags = 2;
+	}
+
+    optional uint32 number32 = 1;
+    optional uint64 number64 = 2;
+
+    repeated uint32 list_number32 = 3;
+    repeated uint64 list_number64 = 4;
+
+	repeated .ComplexProtoMessage.InnerMessage messages = 5;
+	repeated .ComplexProtoMessage.InnerBuffer buffers = 6;
+}

steam/util/__init__.py

@@ -4,7 +4,16 @@
 import struct
 import socket
 import sys
+import six
 from six.moves import xrange as _range
+from types import GeneratorType as _GeneratorType
+from google.protobuf.internal.python_message import GeneratedProtocolMessageType as _ProtoMessageType
+
+if six.PY2:
+    _list_types = list, xrange, _GeneratorType
+else:
+    _list_types = list, range, _GeneratorType, map, filter
+
 
 def ip_from_int(ip):
     """Convert IP to :py:class:`int`
@@ -61,13 +70,17 @@ def proto_to_dict(message):
     :param message: protobuf message instance
     :return: parameters and their values
     :rtype: dict
+    :raises: :class:`.TypeError` if ``message`` is not a proto message
     """
+    if not isinstance(message.__class__, _ProtoMessageType):
+        raise TypeError("Expected `message` to be a instance of protobuf message")
+
     data = {}
 
     for desc, field in message.ListFields():
         if desc.type == desc.TYPE_MESSAGE:
             if desc.label == desc.LABEL_REPEATED:
-                data[desc.name] = map(proto_to_dict, field)
+                data[desc.name] = list(map(proto_to_dict, field))
             else:
                 data[desc.name] = proto_to_dict(field)
         else:
@@ -86,6 +99,11 @@ def proto_fill_from_dict(message, data, clear=True):
     :return: value of message paramater
     :raises: incorrect types or values will raise
     """
+    if not isinstance(message.__class__, _ProtoMessageType):
+        raise TypeError("Expected `message` to be a instance of protobuf message")
+    if not isinstance(data, dict):
+        raise TypeError("Expected `data` to be of type `dict`")
+
     if clear: message.Clear()
     field_descs = message.DESCRIPTOR.fields_by_name
 
@@ -94,24 +112,27 @@ def proto_fill_from_dict(message, data, clear=True):
 
         if desc.type == desc.TYPE_MESSAGE:
             if desc.label == desc.LABEL_REPEATED:
-                if not isinstance(val, list):
-                    raise TypeError("Expected %s to be of type list, got %s" % (
-                        repr(key), type(val)
-                        ))
+                if not isinstance(val, _list_types):
+                    raise TypeError("Expected %s to be of type list, got %s" % (repr(key), type(val)))
+
+                list_ref = getattr(message, key)
+
+                # Takes care of overwriting list fields when merging partial data (clear=False)
+                if not clear: del list_ref[:]  # clears the list
 
                 for item in val:
                     item_message = getattr(message, key).add()
                     proto_fill_from_dict(item_message, item)
             else:
                 if not isinstance(val, dict):
-                    raise TypeError("Expected %s to be of type dict, got %s" % (
-                        repr(key), type(dict)
-                        ))
+                    raise TypeError("Expected %s to be of type dict, got %s" % (repr(key), type(dict)))
 
                 proto_fill_from_dict(getattr(message, key), val)
         else:
-            if isinstance(val, list):
-                getattr(message, key).extend(val)
+            if isinstance(val, _list_types):
+                list_ref = getattr(message, key)
+                if not clear: del list_ref[:]  # clears the list
+                list_ref.extend(val)
             else:
                 setattr(message, key, val)