describe("Array", function () {
  describe(".push()", function () {
    it("should append a value", function () {
      var arr = [];
      arr.push("foo");
      arr.push("bar");
      expect(arr[0]).to.equal("foo");
      expect(arr[1]).to.equal("bar");
    });

    it("should return the length", function () {
      var arr = [];
      var n = arr.push("foo");
      expect(n).to.equal(1);
      n = arr.push("bar");
      expect(n).to.equal(2);
    });

    describe("with many arguments", function () {
      it("should add the values", function () {
        var arr = [];
        arr.push("foo", "bar");
        expect(arr[0]).to.equal("foo");
        expect(arr[1]).to.equal("bar");
      });
    });
  });

  describe(".unshift()", function () {
    it("should prepend a value", function () {
      var arr = [1, 2, 3];
      arr.unshift("foo");
      expect(arr[0]).to.equal("foo");
      expect(arr[1]).to.equal(1);
    });

    it("should return the length", function () {
      var arr = [];
      var n = arr.unshift("foo");
      expect(n).to.equal(1);
      n = arr.unshift("bar");
      expect(n).to.equal(2);
    });

    describe("with many arguments", function () {
      it("should add the values", function () {
        var arr = [];
        arr.unshift("foo", "bar");
        expect(arr[0]).to.equal("foo");
        expect(arr[1]).to.equal("bar");
      });
    });
  });

  describe(".pop()", function () {
    it("should remove and return the last value", function () {
      var arr = [1, 2, 3];
      expect(arr.pop()).to.equal(3);
      expect(arr.pop()).to.equal(2);
      expect(arr).to.have.length(1);
    });
  });

  describe(".shift()", function () {
    it("should remove and return the first value", function () {
      var arr = [1, 2, 3];
      expect(arr.shift()).to.equal(1);
      expect(arr.shift()).to.equal(2);
      expect(arr).to.have.length(1);
    });
  });
});
