}

    @Override
    public O apply(I input) {
      applyCount++;
      return delegate.apply(input);
    }

    void verifyCallCount(int expected) {
      assertThat(applyCount).isEqualTo(expected);
    }
  }

  private static <X extends Throwable, V> Function<X, V> unexpectedFunction() {
    return new Function<X, V>() {
      @Override
      public V apply(X t) {

    }

    @Override
    public O apply(I input) {
      applyCount++;
      return delegate.apply(input);
    }

    void verifyCallCount(int expected) {
      assertThat(applyCount).isEqualTo(expected);
    }
  }

  private static <X extends Throwable, V> Function<X, V> unexpectedFunction() {
    return new Function<X, V>() {
      @Override
      public V apply(X t) {