fake_merge_target.rs

#[test]
fn test_fake_merge_target_message() {
    let mut cluster = new_node_cluster(0, 4);
    configure_for_merge(&mut cluster);
    let pd_client = Arc::clone(&cluster.pd_client);
    pd_client.disable_default_operator();

    let r1 = cluster.run_conf_change();
    pd_client.must_add_peer(r1, new_peer(2, 2));
    pd_client.must_add_peer(r1, new_peer(3, 3));
    pd_client.must_add_peer(r1, new_learner_peer(4, 4));

    cluster.must_put(b"k1", b"v1");
    cluster.must_put(b"k3", b"v3");
    for i in 1..4 {
        must_get_equal(&cluster.get_engine(i), b"k1", b"v1");
        must_get_equal(&cluster.get_engine(i), b"k3", b"v3");
    }

    let region = pd_client.get_region(b"k1").unwrap();
    cluster.must_split(&region, b"k2");
    let left = pd_client.get_region(b"k1").unwrap();
    let right = pd_client.get_region(b"k3").unwrap();

    let schedule_merge_fp = "on_schedule_merge";
    fail::cfg(schedule_merge_fp, "return()").unwrap();

    cluster.must_try_merge(right.get_id(), left.get_id());
    // Wait until all peer apply prepare merge
    sleep_ms(100);

    // isolate peer 4
    cluster.stop_node(4);

    // remove peer from target region to trigger rollback.
    pd_client.must_remove_peer(left.get_id(), find_peer(&left, 2).unwrap().clone());
    must_get_none(&cluster.get_engine(2), b"k1");

    fail::remove(schedule_merge_fp);
    // wait until merge rollback
    sleep_ms(100);

    // isolate peer 3
    cluster.stop_node(3);

    // remove and recover peer 4 so it will destroy itself by tombstone message
    pd_client.must_remove_peer(right.get_id(), new_learner_peer(4, 4));
    cluster.run_node(4).unwrap();
    must_get_none(&cluster.get_engine(4), b"k3");

    // isolate peer 1 and peer 2, so peer 3 will send message to peer 4
    cluster.stop_node(1);
    cluster.stop_node(2);

    // recover peer 3, it will send message to peer 4 and responses by a gc message with merge target
    // thus destroy itself
    cluster.run_node(3).unwrap();
    // wait destroy
    sleep_ms(500);
    must_get_equal(&cluster.get_engine(3), b"3", b"v3");
}