False positive in lambda inside a method returning Optional

[Tuupertunut]

If in a method that returns Optional, a lambda expression returns something else than Optional, that lambda gives a false positive warning of not returning Optional.

public Optional<Object> getSomeOptional() {
    Function<String, String> f = (String s) -> {
        return "text";
    };
    return Optional.empty();
}

In the above example, the return "text" correctly returns a String, but Netbeans still gives the following warning:
Convert to Optional.ofNullable()/Optional.of(). The return value should be an Optional instance for a method with a return value java.util.Optional.

The warning probably thinks return "text" is a return statement of the method, even though it really is a return statement of the lambda.