some-every.test.js

describe("#hasOddNumber", function () {
    it("returns true if there is at least one odd number in the array", function () {
      expect(hasOddNumber([1, 2, 2, 2, 2, 2, 4])).toEqual(true);
    });
    it("returns false if there are no odd numbers in the array", function () {
      expect(hasOddNumber([2, 2, 2, 2, 2, 4])).toEqual(false);
    });
  });
  
  describe("#hasAZero", function () {
    it("returns true if the number contains at least one 0", function () {
      expect(hasAZero(33321232131012)).toEqual(true);
    });
    it("returns false if the number does not have any zeros", function () {
      expect(hasAZero(1212121)).toEqual(false);
    });
  });
  
  describe("#hasOnlyOddNumbers", function () {
    it("returns true if every number in the array is odd", function () {
      expect(hasOnlyOddNumbers([1, 3, 5, 7])).toEqual(true);
    });
    it("returns false if there is one or more even numbers ", function () {
      expect(hasOnlyOddNumbers([1, 2, 3, 5, 7])).toEqual(false);
    });
  });
  
  describe("#hasNoDuplicates", function () {
    it("returns true if there are no duplicates in the array", function () {
      expect(hasNoDuplicates([1, 2, 3, 1])).toEqual(false);
    });
    it("returns false if there are duplicates in the array", function () {
      expect(hasNoDuplicates([1, 2, 3])).toEqual(true);
    });
  });
  
  describe("#hasCertainKey", function () {
    var arr = [
      { first: "Elie", last: "Schoppik" },
      { first: "Tim", last: "Garcia", isCatOwner: true },
      { first: "Matt", last: "Lane" },
      { first: "Colt", last: "Steele", isCatOwner: true },
    ];
    it("returns true if every object in the array contains a certain key", function () {
      expect(hasCertainKey(arr, "first")).toEqual(true);
    });
    it("returns false if every object in the array does not contain a certain key", function () {
      expect(hasCertainKey(arr, "isCatOwner")).toEqual(false);
    });
  });
  
  describe("#hasCertainValue", function () {
    var arr = [
      { title: "Instructor", first: "Elie", last: "Schoppik" },
      { title: "Instructor", first: "Tim", last: "Garcia", isCatOwner: true },
      { title: "Instructor", first: "Matt", last: "Lane" },
      { title: "Instructor", first: "Colt", last: "Steele", isCatOwner: true },
    ];
    it("returns true if every object in an array has the same value for some key", function () {
      expect(hasCertainValue(arr, "title", "Instructor")).toEqual(true);
    });
    it("returns false if every object in an array does not have the same value for some key", function () {
      expect(hasCertainValue(arr, "first", "Elie")).toEqual(false);
    });
  });