it("should add immediate and dispose to given subscribable", () => {
            const obs = ko.observable("test").extend({ delay: 10 }) as delayExtender.DelayedObservable<string>;
            obs.immediate.should.be.a.Function;
            ko.isSubscribable(obs.immediate).should.be.true;

            obs.dispose.should.be.a.Function;
        });

        it("should return same value if given parameter is an observable", () => {
            var value = ko.observable(commonHelpers.createNoteArray()),
                result = utils.createObservable(value);

            ko.isSubscribable(result).should.be.ok;
            result.should.equal(value);
        });

export function setMaybeObservable<T>(obj: Object, prop: string, newValue: T): void {
    const value = obj[prop];
    
    if (ko.isSubscribable(value)) {
        value(newValue);
    }
    else {
        obj[prop] = newValue;
    }
}

export function maybeObservable<T>(value: MaybeSubscribable<T>, _default?: T): MaybeSubscribable<T> {
    if (typeof value === "undefined" || value === null) {
        return _default;
    }
    
    if (ko.isSubscribable(value)) {
        return value;
    }

    return value;
}

export function createObservableArray(value: any, mapFunction?: (obj: any) => any, context?: any): ko.ObservableArray<any> {
    if (typeof value === "undefined") {
        return ko.observableArray();
    }

    if (ko.isSubscribable(value) && Array.isArray(value())) {
        return value;
    }

    if (Array.isArray(value) && typeof mapFunction === "function") {
        value = value.map(mapFunction, context);
    }

    return ko.observableArray(value);
}

 it("should return a valid subscribable", () => {
     hist = historyObservable();
     ko.isSubscribable(hist).should.be.ok;
 });