return;
    }
    if (isPrimitiveOrNullable(invokable.getParameters().get(paramIndex))) {
      return; // there's nothing to test
    }
    @Nullable Object[] params = buildParamList(invokable, paramIndex);
    try {
      @SuppressWarnings("unchecked") // We'll get a runtime exception if the type is wrong.
      Invokable<Object, ?> unsafe = (Invokable<Object, ?>) invokable;