Support for empty array

[paslavsky]

I wrote function with two arguments and in some cases I want to pass empty array into that function:

rules_version = '2';
service cloud.firestore {
    match /databases/{database}/documents {
        match /{document=**} {
            allow read, write: if false;
        }

        function validateDocument(requiredFields, optionalFields) {
            let allFields = requiredFields.concat(optionalFields) ;
            let fields = request.resource.data.keys() ;
            return fields.hasAll(requiredFields) && fields.hasOnly(allFields);
        }

        match /my-collections/{doc} {
            allow read: if true;
            allow write: if validateDocument(['foo', 'bar'], []);
        }
    }
}

I see the following error in my IDE:

• <expr> or '[' expected, got ']'

[dalgarins]

Thanks for testing, issue will be fixed on version: 2.5.3