framework/tests/all-systems/Issue2302.java

// Test case for Issue 2302
// https://github.com/typetools/checker-framework/issues/2302

@SuppressWarnings("unchecked")
public class Issue2302 {
  static class StrangeConstructorTypeArgs<V> {
    // The constructor does not use the type parameter V.
    public StrangeConstructorTypeArgs(MyClass<byte[]> abs) {}
  }

  static class MyClass<VALUE> {}

  static StrangeConstructorTypeArgs getStrangeConstructorTypeArgs() {
    // Crash with the diamond operator.
    // Type inference chooses `Object` as the type argument.
    // That is a bug, since it should choose exactly `byte[]`.
    return new StrangeConstructorTypeArgs(new MyClass<>());

    // No crash with an explicit type argument (no diamond operator), no matter what it is.
    // return new StrangeConstructorTypeArgs(new MyClass<byte[]>());
    // return new StrangeConstructorTypeArgs(new MyClass<Integer>());
    // return new StrangeConstructorTypeArgs(new MyClass<Object>());
    // return new StrangeConstructorTypeArgs(new MyClass<@Tainted Object>());
  }
}