Testing a mixin function

Question

I have a mixin function which is as follows -

function mixin(receiver, supplier) {
    for (var property in supplier) {
        if (supplier.hasOwnProperty(property)) {
            receiver[property] = supplier[property];
        }
    }
}

To test this function, I am using the ok method of Qunit -

test('Mixin Test Runner', function () {
    // using OK method
    ok(function () {
        var receiver = {
            name: 'Abul Moksud',
            age: '60'
        };

        var supplier = {
            hands: 2
        };

        mixin(receiver, supplier);

        return receiver.hasOwnProperty('hands') && (receiver.hands === 2);
    }(), "Abul Moksud now has two hands");
});

I am an absolute beginner in both unit testing and QUnit. Is my approach OK here, or is there any better option?

Answer 1

Your code is correct, but can be simplified. ok method usually gets an expression rather than a in-place function that is immediately evaluated.

Here is how I would write this test:

test('Mixin Test Runner', function () {
    var receiver = {
        name: 'Abul Moksud',
        age: '60'
    };

    var supplier = {
        hands: 2
    };

    mixin(receiver, supplier);

    //Assertion phase
    ok(receiver.hasOwnProperty("hands"), "hands property is defined on reciever");
    equal(receiver.hands, 2, "Abul Moksud now has two hands");
});