0-length FixedLengthArray of U8 decodes to []

[kkowalski-reef]

py-scale-codec/scalecodec/types.py

Lines 1925 to 1938 in ee3ab0c

	def process(self):
	if self.element_count:
	if self.runtime_config.get_decoder_class(self.sub_type) is U8:
	self.value_object = self.get_next_bytes(self.element_count)
	return '0x{}'.format(self.value_object.hex())
	else:
	result = []
	for idx in range(self.element_count):
	result.append(self.process_type(self.sub_type).value)
	else:
	result = []
	return result

All other U8 lengths decode to 0x...

Getting an array out of this is very surprising if not outright incorrect

[PushkarOnGithub]

can i try this?? @kkowalski-reef

[kkowalski-reef]

Yeah, sorry, here's a minimal repro:

from scalecodec.base import RuntimeConfigurationObject, ScaleBytes

conf = RuntimeConfigurationObject()

b32_0 = conf.create_scale_object("[u8; 0]", data=ScaleBytes(b""))
print(b32_0.decode())  # []

b32_8 = conf.create_scale_object("[u8; 8]", data=ScaleBytes(b"\x01\x02\x03\x04\x05\x06\x07\x08"))
print(b32_8.decode())  # "0x0102030405060708"

The problem is that self.element_count == 0 immediately returns a []

[kkowalski-reef]

To be clear I'm on 1.2.11, .12 doesn't seem to be addressing this and v2 is apparently in alpha state so I haven't tested that.