Edit in JSFiddle

describe('toThrow', function() {
    it('checks that the expected exception was thrown by the actual', function() {
        var object = {
            doSomething: function() {
                throw new Error("Unexpected error!")
            }
        };
        expect(object.doSomething).toThrow(new Error("Unexpected error!"));
    });
});

execJasmine();