Snake string utils

[arterialist]

No description provided.

[sasha1618]

Let's make a more flexible class:

# https://github.com/ton-blockchain/TEPs/blob/master/text/0064-token-data-standard.md#data-serialization
class SnakeData:
	prefix = 0x00
	prefix_len = 8

	@classmethod
	def write(cls, builder: 'Builder', data: Union[bytes, bytearray], prefixed=False):
		if prefixed:
			builder.store_bits(cls.prefix)

		# todo: implement data serialization logic to a given builder (now data is a bytes sequence)
		# implementation example
		builders = []

		while len(data) > 0:
			max_bytes = builder.builder_rembits >> 3
			bits, data = data[:max_bytes], data[max_bytes:]

			builder.store_bytes(bits)
			builders.append(builder)

			builder = begin_cell()

		if len(builders) > 1:
			last_builder = builders[-1]

			for builder in reversed(builders[:-1]):
				builder.store_ref(last_builder.end_cell())
				last_builder = builder

		return builders[0]


	@classmethod
	def read(cls, cs, prefixed=False):
		data = bytearray()

		if prefixed:
			assert cs.load_bits(cls.prefix_len) == cls.prefix

		while True:
			data.extend(cs.load_bytes(cs.slice_bits >> 3))

			if cs.slice_refs > 0:
				cs = cs.load_ref().begin_parse()
				continue

			break

		return data

Usage:

my_text = "foobar" * 40

builder = begin_cell()
SnakeData.write(builder, bytes(text, encoding="utf8"), prefixed=False)

Please, put it in the utils/_data.py folder

[sasha1618]

We may write

class SnakeData:
    """
    Implementation of the TON data standard: https://github.com/ton-blockchain/TEPs/blob/master/text/0064-token-data-standard.md#data-serialization
    """

[sasha1618]

Shall we delete this?

[sasha1618]

fixme: Remove

[spookyahell]

This is the only real snake, everything else, including cpython are fake snakes

(I'm very sorry, I have a humor problem.)