branchcache: gather newly closed head in a dedicated set This is part of a series to more clearly split the update in two step. This will allow us to introduce a fast path during update in a future changeset.

from typing import (
    List,
)

version: int

class mpatchError(Exception): ...

def patches(text: bytes, bins: List[bytes]) -> bytes: ...
def patchedsize(orig: int, data: bytes) -> int: ...