addSubtractUnitTests

describe("calc func", () => {
    let returnedObj;

    beforeEach(function () {
        returnedObj = createCalculator();
    });

    it("asserts type of return", () => {
        assert.equal(typeof returnedObj, "object");
    });

    it("asserts has required properties", () => {
        assert.equal(returnedObj.hasOwnProperty("add"), true);
        assert.equal(returnedObj.hasOwnProperty("subtract"), true);
        assert.equal(returnedObj.hasOwnProperty("get"), true);
    });

    it("asserts value access", () => {
        assert.equal(returnedObj.value, undefined);
    });

    it("asserts add method with number", () => {
        returnedObj.add(6);
        assert.equal(returnedObj.get(), 6);
    });

    it("asserts add method with string", () => {
        returnedObj.add("6");
        assert.equal(returnedObj.get(), 6);
    });

    it("asserts subtract method with number", () => {
        returnedObj.subtract(6);
        assert.equal(returnedObj.get(), -6);
    });

    it("asserts subtract method with string", () => {
        returnedObj.subtract("6");
        assert.equal(returnedObj.get(), -6);
    });
    it("asserts get method", () => {
        returnedObj.add("6");
        returnedObj.add(8);
        returnedObj.subtract(2);

        assert.equal(returnedObj.get(), 12);
    });
});