[jackpot] DefaultRuleUtilities::referencedIn fix for single variable matching

[mbien]

referencedIn(v, in) did not match if in was a single variable.

example:

for(int $i = $from; $i < $to; $i++) {
    $array[$i] = $n;
} 
:: !referencedIn($i, $n) && !matchesAny($n, "$i") /*&& more()*/ =>
java.util.Arrays.fill($array, $n);
;;

needed an extra !matchesAny($n, "$i") to make sure $n is not actually equal to $i. (i+1 would be matched by referencedIn but not i). After this PR && !matchesAny is no longer needed.

• added a small optimization which adds a fast path to the recursion if a result has been already determined.
• couldn't find tests for referencedIn so I added some.

btw the in-editor test integration for rule files is super cool

[JaroslavTulach]

I am amazed by your contributions to Jackpot, Michael. It is great to see someone else than @jlahoda taking care of the tool!

Writing a test as well as changing code is always good thing. I didn't even know we have referencedIn condition. Shouldn't we also improve the documentation to give a nice example of this (and possibly other) conditions?

[mbien]

@JaroslavTulach I do what i can but a lot of this is still black magic to me :)

I am going to rebase this PR for delivery just in case it can be still integrated. This looks fairly low risk to me (I don't think the utility functions are even used in netbeans itself).

[neilcsmith-net]

This looks fairly low risk to me (I don't think the utility functions are even used in netbeans itself).

Not sure how to assess the latter point against bug criteria then, so will take your word on the first point and sneak it in rc3! 😄 Will merge tomorrow, give @jlahoda time to comment if needed.

[jlahoda]

Looks great, BTW!