JS-Testing: leap year specs

leap_year.spec.js

describe('leap year specs', () => {
  describe('A year is a leap year if', () => {
    it('is divisible by 4 but not by 100', () => {
      expect(isLeapYear(2016)).toBeTruthy()
    });
 
    it('is divisible by 400', () => {
      expect(isLeapYear(2000)).toBeTruthy()
    });
  });
 
  describe('A year is *NOT* a leap year if', () => {
    it('is not divisible by 4', () => {
      expect(isLeapYear(3)).toBeFalsy();
    });
    it('is divisible by 100 but not by 400', () => {
      expect(isLeapYear(100)).toBeFalsy();
    });
  });
});