Leap Year Testing Code p5js

leap_test.js

function passOrFail(predicate, expectation, msg) {
  const outcome = (predicate == expectation) ? "PASSED" : "FAILED";
  console.log(`${msg}: ${outcome}`);
}

function expect(predicate, msg) {
  return {
    toBeFalsy: () => passOrFail(predicate, false, msg),
    toBeTruthy: () => passOrFail(predicate, true, msg)
  }
}

function testSuite() {
  expect(isLeap(2015), 'year not divisible by 4 (common year)').toBeFalsy();
  expect(isLeap(2016), 'year divisible by 4, not divisible by 100 (leap year)').toBeTruthy();
  expect(isLeap(2100), 'year divisible by 100, not divisible by 400 (common year)').toBeFalsy();
  expect(isLeap(2000), 'year divisible by 400: leap year').toBeTruthy();
  expect(isLeap(1800),'year divisible by 200, not divisible by 400 (common year)').toBeFalsy();
}

function isLeap(year) {
  // Return true if year is a leap other, otherwise return false. 
};

function setup() {
  testSuite();
}