Function merge_subtrees_root

pub fn merge_subtrees_root(
    left_child: &ChainingValue,
    right_child: &ChainingValue,
    mode: Mode<'_>,
) -> Hash

Compute a root hash from two child chaining values.

See the module level examples, particularly the discussion of valid tree structures. The left and right child chaining values can come from either Hasher::finalize_non_root or merge_subtrees_non_root. “Chaining value” is the academic term for a non-root or non-final hash.

Note that inputs of CHUNK_LEN or less don’t produce any parent nodes and can’t be hashed using this function. In that case you must get the root hash from Hasher::finalize (or just blake3::hash).