let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
assert_eq!(msg_events.len(), 1);
pass_along_path(&nodes[0], &[&nodes[1], &nodes[2]], amt_msat, payment_hash, None, msg_events.pop().unwrap(), true, Some(payment_preimage));
let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
assert_eq!(msg_events.len(), 1);
pass_along_path(&nodes[0], &[&nodes[1], &nodes[2]], amt_msat, payment_hash, None, msg_events.pop().unwrap(), true, Some(payment_preimage));