Fixed ScaleType serialization issues with Array and HashMap types

Author: arjanz

scalecodec/base.py

@@ -164,7 +164,6 @@ def new(self, **kwargs) -> 'ScaleType':
 
         return obj
 
-
     def impl(self, scale_type_cls: type = None, runtime_config=None) -> 'ScaleTypeDef':
         """
 
@@ -286,7 +285,7 @@ def deserialize(self, value_serialized: any):
             return self.value_object
 
         self.value_object = self.type_def.deserialize(value_serialized)
-        self.value_serialized = value_serialized
+        self.value_serialized = self.type_def.serialize(self.value_object)
 
         return self.value_object
 

scalecodec/types.py

@@ -655,7 +655,18 @@ def deserialize(self, value: str) -> str:
         return value
 
 
+class ArrayObject(ScaleType):
+
+    def to_bytes(self) -> bytes:
+        if self.type_def.type_def is not U8:
+            raise ScaleDeserializeException('Only an Array of U8 can be represented as bytes')
+        return self.value_object
+
+
 class Array(ScaleTypeDef):
+
+    scale_type_cls = ArrayObject
+
     def __init__(self, type_def: ScaleTypeDef, length: int):
         self.type_def = type_def
         self.length = length
@@ -715,12 +726,27 @@ def serialize(self, value: Union[list, bytes]) -> Union[list, str]:
             return f'0x{value.hex()}'
 
     def deserialize(self, value: Union[list, str, bytes]) -> Union[list, bytes]:
+
+        if type(value) not in [list, str, bytes]:
+            raise ScaleDeserializeException('value should be of type list, str or bytes')
+
         if type(value) is str:
             if value[0:2] == '0x':
-                return bytes.fromhex(value[2:])
+                value = bytes.fromhex(value[2:])
             else:
-                return value.encode()
-        else:
+                value = value.encode()
+
+        if len(value) != self.length:
+            raise ScaleDeserializeException('Length of array does not match size of value')
+
+        if type(value) is bytes:
+            if self.type_def is not U8:
+                raise ScaleDeserializeException('Only an Array of U8 can be represented as (hex)bytes')
+
+            return value
+
+        if type(value) is list:
+
             value_object = []
 
             for item in value:
@@ -793,7 +819,13 @@ def decode(self, data: ScaleBytes) -> list:
         return value
 
     def serialize(self, value: list) -> list:
-        return [(k.value_serialized, v.value_serialized) for k, v in value]
+        output = []
+        for k, v in value:
+            if type(k) is ScaleType and type(v) is ScaleType:
+                output.append((k.value_serialized, v.value_serialized))
+            else:
+                output.append((k, v))
+        return output
 
     def deserialize(self, value: list) -> list:
         return [(self.key_def.deserialize(k), self.value_def.deserialize(v)) for k, v in value]
@@ -833,12 +865,20 @@ def decode(self, data: ScaleBytes) -> bytearray:
     def serialize(self, value: bytearray) -> str:
         return f'0x{value.hex()}'
 
-    def deserialize(self, value: str) -> bytearray:
-        if type(value) is str:
+    def deserialize(self, value: Union[bytes, str, list]) -> bytes:
+
+        if type(value) in (list, bytearray):
+            value = bytes(value)
+
+        elif type(value) is str:
             if value[0:2] == '0x':
-                value = bytearray.fromhex(value[2:])
+                value = bytes.fromhex(value[2:])
             else:
                 value = value.encode('utf-8')
+
+        if type(value) is not bytes:
+            raise ScaleDeserializeException(f'Cannot deserialize type "{type(value)}"')
+
         return value
 
     def example_value(self, _recursion_level: int = 0, max_recursion: int = TYPE_DECOMP_MAX_RECURSIVE):
@@ -860,13 +900,19 @@ def serialize(self, value: str) -> str:
     def deserialize(self, value: str) -> str:
         return value
 
-
     def create_example(self, _recursion_level: int = 0):
         return 'String'
 
 
+class HashDefObject(ScaleType):
+    def to_bytes(self) -> bytes:
+        return self.value_object
+
+
 class HashDef(ScaleTypeDef):
 
+    scale_type_cls = HashDefObject
+
     def __init__(self, bits: int):
         super().__init__()
         self.bits = bits
@@ -897,6 +943,10 @@ def serialize(self, value: bytes) -> str:
     def deserialize(self, value: Union[str, bytes]) -> bytes:
         if type(value) is str:
             value = bytes.fromhex(value[2:])
+
+        if type(value) is not bytes:
+            raise ScaleDeserializeException('value should be of type str or bytes')
+
         return value
 
     def example_value(self, _recursion_level: int = 0, max_recursion: int = TYPE_DECOMP_MAX_RECURSIVE):

test/test_boolean.py

@@ -47,6 +47,11 @@ def test_bool_encode_decode(self):
 
         self.assertEqual(value, scale_obj.value)
 
+    def test_bool_encode_false(self):
+        scale_obj = Bool().new()
+        data = scale_obj.encode(False)
+        self.assertEqual(ScaleBytes("0x00"), data)
+
 
 if __name__ == '__main__':
     unittest.main()