def test_iterator_create_from_buffer(self):
engine = test_engine()
buffer = vm.BufferStackItem(b'\x03\x04')
engine.push(buffer)
r = engine.invoke_syscall_by_name("System.Iterator.Create")
self.assertIsInstance(r, ByteArrayWrapper)
with self.assertRaises(ValueError) as context:
r.key()
self.assertEqual(
"Cannot call 'key' without having advanced the iterator at least once",
str(context.exception))
with self.assertRaises(ValueError) as context:
r.value()
self.assertEqual(
"Cannot call 'value' without having advanced the iterator at least once",
str(context.exception))
self.assertTrue(r.next())
self.assertEqual(vm.IntegerStackItem(0), r.key())
self.assertEqual(vm.IntegerStackItem(3), r.value())
self.assertTrue(r.next())
self.assertEqual(vm.IntegerStackItem(1), r.key())
self.assertEqual(vm.IntegerStackItem(4), r.value())
self.assertFalse(r.next())
self.assertEqual(vm.IntegerStackItem(1), r.key())
self.assertEqual(vm.IntegerStackItem(4), r.value())
def test_deserialize_buffer(self):
data = b'\x01\x02'
b = vm.BufferStackItem(data)
b_serialized = contracts.BinarySerializer.serialize(b, 999)
new_b = contracts.BinarySerializer.deserialize(b_serialized, 999,
self.reference_counter)
self.assertIsInstance(new_b, vm.BufferStackItem)
self.assertEqual(new_b.to_array(), b.to_array())
def test_deserialize_with_invalid_format(self):
data = b'\x01\x02'
b = vm.BufferStackItem(data)
b_serialized = bytearray(contracts.BinarySerializer.serialize(b, 999))
b_serialized[0] = 0xFF # non existing stackitem type
with self.assertRaises(ValueError) as context:
contracts.BinarySerializer.deserialize(b_serialized, 999,
self.reference_counter)
self.assertEqual("Invalid format", str(context.exception))
def deserialize(data: bytes, max_size: int, max_item_size: int,
reference_counter: vm.ReferenceCounter) -> vm.StackItem:
"""
Deserialize data into a stack item.
Args:
data: byte array of a serialized stack item.
max_size: data reading limit for Array, Struct and Map types.
max_item_size: data reading limit for ByteString or Buffer types.
reference_counter: a valid reference counter instance. Get's passed into reference stack items.
"""
if len(data) == 0:
raise ValueError("Nothing to deserialize")
deserialized: List[Union[vm.StackItem, PlaceHolder]] = []
to_deserialize = 1
with serialization.BinaryReader(data) as reader:
while not to_deserialize == 0:
to_deserialize -= 1
item_type = vm.StackItemType(reader.read_byte()[0])
if item_type == vm.StackItemType.ANY:
deserialized.append(vm.NullStackItem())
elif item_type == vm.StackItemType.BOOLEAN:
deserialized.append(vm.BooleanStackItem(
reader.read_bool()))
elif item_type == vm.StackItemType.INTEGER:
deserialized.append(
vm.IntegerStackItem(
vm.BigInteger(
reader.read_var_bytes(
vm.IntegerStackItem.MAX_SIZE))))
elif item_type == vm.StackItemType.BYTESTRING:
deserialized.append(
vm.ByteStringStackItem(
reader.read_var_bytes(max_item_size)))
elif item_type == vm.StackItemType.BUFFER:
deserialized.append(
vm.BufferStackItem(
reader.read_var_bytes(max_item_size)))
elif item_type in [
vm.StackItemType.ARRAY, vm.StackItemType.STRUCT
]:
count = reader.read_var_int(max_size)
deserialized.append(PlaceHolder(item_type, count))
to_deserialize += count
elif item_type == vm.StackItemType.MAP:
count = reader.read_var_int(max_size)
deserialized.append(PlaceHolder(item_type, count))
to_deserialize += count * 2
else:
raise ValueError("Invalid format")
temp: List[vm.StackItem] = []
while len(deserialized) > 0:
item = deserialized.pop()
if type(item) == PlaceHolder:
item = cast(PlaceHolder, item)
if item.type == vm.StackItemType.ARRAY:
array = vm.ArrayStackItem(reference_counter)
for _ in range(0, item.count):
array.append(temp.pop())
temp.append(array)
elif item.type == vm.StackItemType.STRUCT:
struct = vm.StructStackItem(reference_counter)
for _ in range(0, item.count):
struct.append(temp.pop())
temp.append(struct)
elif item.type == vm.StackItemType.MAP:
m = vm.MapStackItem(reference_counter)
for _ in range(0, item.count):
k = temp.pop()
k = cast(vm.PrimitiveType, k)
v = temp.pop()
m[k] = v
temp.append(m)
else:
item = cast(vm.StackItem, item)
temp.append(item)
return temp.pop()
