final

pub fn final(self: *const Blake3, out_slice: []u8) void {
    // Starting with the Output from the current chunk, compute all the
    // parent chaining values along the right edge of the tree, until we
    // have the root Output.
    var output = self.chunk_state.output();
    var parent_nodes_remaining: usize = self.cv_stack_len;
    while (parent_nodes_remaining > 0) {
        parent_nodes_remaining -= 1;
        output = parentOutput(
            self.cv_stack[parent_nodes_remaining],
            output.chainingValue(),
            self.key,
            self.flags,
        );
    }
    output.rootOutputBytes(out_slice);
}