Make use of the fact that DataOutput's buffer is never None

We initialize the buffer at the constructor and never set it to
None on any of the code paths. Therefore, None checks are not
necessary.

Author: mdumandag

hazelcast/serialization/output.py

@@ -119,8 +119,6 @@ def write_object(self, val):
         self._service.write_object(self, val)
 
     def to_byte_array(self):
-        if self._buffer is None or self._pos == 0:
-            return bytearray()
         return self._buffer[:self._pos]
 
     def is_big_endian(self):
@@ -146,18 +144,14 @@ def _write_array_fnc(self, val, item_write_fnc):
 
     def _ensure_available(self, length):
         if self._available() < length:
-            if self._buffer is not None:
-                buffer_length = len(self._buffer)
-                new_length = max(buffer_length << 1, buffer_length + length)
-                new_buffer = bytearray(new_length)
-                new_buffer[:self._pos] = self._buffer[:self._pos]
-                self._buffer = new_buffer
-            else:
-                new_length = length * 2 if length > self._init_size // 2 else self._init_size
-                self._buffer = bytearray(new_length)
+            buffer_length = len(self._buffer)
+            new_length = max(buffer_length << 1, buffer_length + length)
+            new_buffer = bytearray(new_length)
+            new_buffer[:self._pos] = self._buffer[:self._pos]
+            self._buffer = new_buffer
 
     def _available(self):
-        return len(self._buffer) - self._pos if self._buffer is not None else 0
+        return len(self._buffer) - self._pos
 
     def __repr__(self):
         from binascii import hexlify

tests/serialization/serialization_test.py

@@ -63,7 +63,7 @@ def test_python_pickle_serialization_with_super_type(self):
         self.assertEqual(obj, obj2)
 
     def test_null_data(self):
-        data = Data()
+        data = Data(bytearray(0))
         obj = self.service.to_object(data)
         self.assertIsNone(obj)
 
@@ -73,7 +73,7 @@ def test_none_serialize(self):
         self.assertIsNone(data)
 
     def test_serialize_data(self):
-        data = Data()
+        data = Data(bytearray(0))
         obj = self.service.to_data(data)
         self.assertTrue(isinstance(obj, Data))