Function taproot_tree_helper

test/functional/test_framework/script.py:863–900

(scripts)

    return TaggedHash("TapSighash", TaprootSignatureMsg(*args, **kwargs))

def taproot_tree_helper(scripts):
    if len(scripts) == 0:
        return ([], bytes())
    if len(scripts) == 1:
        # One entry: treat as a leaf
        script = scripts[0]
        assert not callable(script)
        if isinstance(script, list):
            return taproot_tree_helper(script)
        assert isinstance(script, tuple)
        version = LEAF_VERSION_TAPSCRIPT
        name = script[0]
        code = script[1]
        if len(script) == 3:
            version = script[2]
        assert_equal(version & 1, 0)
        assert isinstance(code, bytes)
        h = TaggedHash("TapLeaf", bytes([version]) + ser_string(code))
        if name is None:
            return ([], h)
        return ([(name, version, code, bytes(), h)], h)
    elif len(scripts) == 2 and callable(scripts[1]):
        # Two entries, and the right one is a function
        left, left_h = taproot_tree_helper(scripts[0:1])
        right_h = scripts[1](left_h)
        left = [(name, version, script, control + right_h, leaf) for name, version, script, control, leaf in left]
        right = []
    else:
        # Two or more entries: descend into each side
        split_pos = len(scripts) // 2
        left, left_h = taproot_tree_helper(scripts[0:split_pos])
        right, right_h = taproot_tree_helper(scripts[split_pos:])
        left = [(name, version, script, control + right_h, leaf) for name, version, script, control, leaf in left]
        right = [(name, version, script, control + left_h, leaf) for name, version, script, control, leaf in right]
    if right_h < left_h:
        right_h, left_h = left_h, right_h
    h = TaggedHash("TapBranch", left_h + right_h)
    return (left + right, h)

# A TaprootInfo object has the following fields:
# - scriptPubKey: the scriptPubKey (witness v1 CScript)