Lodash vanilla utility - shnigidash

shnigidash.js

// UTILITY
const cars = [
  { type: 'mazda',  driven: 14020, active: true },
  { type: 'volvo',  driven: 404324, active: false },
  { type: 'nissan', driven: 135223, active: true }
];

// MAP FUNCTIONS
const shnigimap = (arr, mapfunc) => {
  const resultArray = [];
  for (let i = 0; i < arr.length; i++) {
    const result = mapfunc(arr[i])
    resultArray.push(result);
  }
  return resultArray;
};

Array.prototype.shnigimap = function(mapfunc) {
  console.log(this)
  const resultArray = [];
  for (let i = 0; i < this.length; i++) {
    const result = mapfunc(this[i])
    resultArray.push(result);
  }
  return resultArray;
};

//console.log('map example: ', shnigimap([1,2,3,4], num => num * 2));
//console.log('map example 2: ', [1,2,3,4].shnigimap(num => num * 4));

// FILTER FUNCTIONS
const shnigifilter = (arr, filterfunc) => {
  const resultArray = [];
  for (let i = 0; i < arr.length; i++) {
    const result = filterfunc(arr[i]);
    if (result) resultArray.push(arr[i]);
  }
  return resultArray;
};

Array.prototype.shnigifilter = function(filterfunc) {
  const resultArray = [];
  for (let i = 0; i < this.length; i++) {
    const result = filterfunc(this[i]);
    if (result) resultArray.push(this[i]);
  }
  return resultArray;
};

//console.log('filter example: ', shnigifilter([1,2,3,4,5,6,7,8], num => num < 5));
//console.log('filter example 2: ', [1,2,3,4,5,6,7,8].shnigifilter(num => num <= 2));

// REDUCE FUNCTIONS

const shnigireduce = (arr, reducer, initialValue) => {
  let accumulator = initialValue ?? 0;
  for (let i = 0; i < arr.length; i++) {
    accumulator = reducer(accumulator, arr[i]);
  }
  return accumulator;
};

Array.prototype.shnigireduce = function(reducer, initialValue){
  let accumulator = initialValue ?? 0;
  for (let i = 0; i < this.length; i++) {
    accumulator = reducer(accumulator, this[i]);
  }
  return accumulator;
};

// console.log('Reduce example: ', shnigireduce([1,2,3,4], (acc, val) => acc + val, 5));
// console.log('Reduce example: ', [1,2,3,4].shnigireduce((acc, val) => acc + val, 5));
 // console.log('Reduce example 2: ', cars.shnigireduce((acc, val) => val.driven + acc));

// FIND FUNCTIONS

const findItem = (arr, findfunc) => {
  for (let i = 0; i < arr.length; i++) {
    const result = findfunc(arr[i]);
    if (result) {
      return arr[i];
    }
  }
  return undefined;
};

const findObject = (arr, object) => {
  const objectEntries = Object.entries(object);
   for (let i = 0; i < arr.length; i++) {
    let counter = 0;
    for (let o = 0; o < objectEntries.length; o++) {
      const [key, value] = objectEntries[o];
      if (arr[i][key] === value) {
           counter++;
      }
    }
      if (counter === objectEntries.length) {
         return arr[i];
      }
  }
  return null;
};

const shnigifind = (arr, find) => {
if (typeof find === 'function') {
    return findItem(arr, find);
} else if (typeof find === 'object') {
    return findObject(arr, find);
}
};

// shnigifind(cars, { type: 'mazda', active: true })
// console.log('find example 1: ', shnigifind(cars, car => car.type === 'volvo'));
// console.log('find example 2: ', shnigifind(cars, { type: 'volvo', active: false }));