"Example Factory" a factory method used to instantiate the SUT object with canonical values, overwriting only the properties relevant to the test case.

gistfile1.js

var SeminarFactory = {
    create: function (overwrite) {
        var defaultData,
            objectData;

        defaultData = {
            name: 'JavaScript basics',
            price: 100
        };

        objectData = Object.extend(defaultData, overwrite);

        return Seminar.create(objectData.name, objectData.price);
    }
};

describe('Seminar', function () {
    it('has a name', function () {
        var seminar = SeminarFactory.create({name: 'JavaScript'});

        expect(seminar.getName()).toEqual('JavaScript');
    });

    it('has a price', function () {
        var seminar = SeminarFactory.create({price: 10});

        expect(seminar.getPrice()).toEqual(10);
    });
});