@kowo0403hk/lotide/takeUntil.js

lotide library by LHL Bootcamp student

// implement the takeUntil function, which will take in two params: 1. array, 2. callback

const assertArraysEqual = function(arr1, arr2) {
  if (eqArrays(arr1, arr2)) {
    console.log(`\u2705\u2705\u2705 Assertion Passed: ${arr1} === ${arr2}`);
  } else {
    console.log(`\u26d4\u26d4\u26d4 Assertion Failed: ${arr1} !== ${arr2}`);
  }
};

const eqArrays = function(arr1, arr2) {
  // eliminate edge cases: arrays are not having same length, and either of the input is not array
  if (arr1.length !== arr2.length || !(Array.isArray(arr1)) || !(Array.isArray(arr2))) {
    return false;
  }

  for (let i = 0; i < arr1.length; i++) {
    if (arr1[i] !== arr2[i]) {
      return false;
    }
  }
  return true;
};


const takeUntil = (array, callback) => {
  const results = [];
  for (let item of array) {
    if (!(callback(item))) {
      results.push(item);
    } else return results;
  }
};

// test case

const data1 = [1, 2, 5, 7, 2, -1, 2, 4, 5];
const results1 = takeUntil(data1, x => x < 0);
console.log(results1);

console.log('---');

const data2 = ["I've", "been", "to", "Hollywood", ",", "I've", "been", "to", "Redwood"];
const results2 = takeUntil(data2, x => x === ',');
console.log(results2);


// Expected Output
// [ 1, 2, 5, 7, 2 ]
// --
// [ 'I\'ve', 'been', 'to', 'Hollywood' ]

assertArraysEqual(results1, [1, 2, 5, 7, 2]);
assertArraysEqual(results2, ["I've", "been", "to", "Hollywood"]);