max/min not working with array

[sauravkkr]

Rule: {"max":[{"var" : "integers"}]}
Data: {"integers":[1,2,3,4,5]}
Always return null.

[jwadhams]

I don't think the documentation is clear enough.

As implemented, max returns the largest argument (and assumes all arguments are numeric or coercable to a numeric) but no implementation really knows what to do with an argument that is an array, and the shared unit tests don't cover it.

In PHP:

JWadhams\JsonLogic::apply(['max'=>[1,2,3]]); 
// returns 3
JWadhams\JsonLogic::apply(['max'=>[[1,2,3]]]);
// returns [1,2,3]

In JavaScript:

jsonLogic.apply({"max":[1,2,3]})
// returns 3
jsonLogic.apply({"max":[[1,2,3]]})
// returns NaN

You could pretty easily write a version in your language of choice that expects a single array argument. Here's a JavaScript approach:

jsonLogic.add_operation('array_max', function (a) {
    return Math.max.apply(this, a);
});
jsonLogic.apply({"array_max":[[1,2,3]]})
// returns 3
jsonLogic.apply(
    {"array_max":[{"var":"integers"}]},
    {"integers":[1,2,3,4,5]}
);
// returns 5