checker/tests/fenum/CastsFenum.java

import org.checkerframework.checker.fenum.qual.Fenum;

public class CastsFenum {
  @Fenum("A") Object fa;

  void m(Object p, @Fenum("A") Object a) {
    fa = (Object) a;
    // :: error: (assignment)
    fa = (Object) p;

    // TODO: How can we test the behavior for
    // instanceof? It should be the same as for casts.
    // if (p instanceof Object) {
  }
}