function accessFirstItem(array) {
  return array[0];
}

function accessThirdItem(array) {
  return array[2];
}

// tests

function testFunctionWorks(fn, input, expected) {
  if (fn(input) === expected) {
    console.log(`SUCCESS: "${fn.name}" works on [${input}]`);
    return true;
  } else {
    console.log(
      `FAILURE: ${fn.name}([${input}]) should be ${expected} but was ${fn(
        input
      )}`
    );
    return false;
  }
}

function runTests() {
  var list = [1, 4, 9, 16, 25];
  var item1 = 1;
  var item2 = 9;

  var testResults = [
    testFunctionWorks(accessFirstItem, list, item1),
    testFunctionWorks(accessThirdItem, list, item2),
  ];

  var numPassing = testResults.filter(function(result) {
    return result;
  }).length;
  console.log(numPassing + ' out of ' + testResults.length + ' tests passing.');
}

runTests();