Why isn't this jasmine spy working?

There must be something I'm not understanding about how to use Jasmine spies. I'm putting together curriculum to explain this to students, hence the dummy example.

source:

function addEmotion(str, emotion) {
    if (emotion === "excitement") {
        addExcitement(str);
    } else {
        addSadness(str);
    }
}

function addExcitement(str) {
    return str + "!!!";
}

spec:

describe("addEmotion function", function () {
    var addExcitement;
    beforeEach(function () {
        addExcitement = jasmine.createSpy("addExcitement");
    });

    it("should call addExcitement when emotion is 'excitement'", function () {
        var str = "Hey there";
        addEmotion(str, "excitement");
        expect(addExcitement).toHaveBeenCalled();
    });
});

Sorry in advance if I'm missing something really obvious. I'm still pretty new to Jasmine.