immutability-helper.js

import update from 'immutability-helper';
import {cloneDeep} from 'lodash';

const selectedChoice = {isChosen: true};
const choices = [selectedChoice, selectedChoice, selectedChoice];
const options = {choices: choices};
const selectedOptions = [options, options];
const OPTION_INDEX = 0;
const CHOICE_INDEX = 1;

function unselectChoiceSpreadOperator(optionIndex, choiceIndex) {
  return selectedOptions.map((option, currentOptionIndex) => {
    if (currentOptionIndex === optionIndex) {
      return {
        ...option,
        choices: option.choices.map((choice, currentChoiceIndex) => {
          if (currentChoiceIndex === choiceIndex ) {
            return {
              ...choice,
              isChosen: false
            }
          } 
          return choice;
        })
      }
    } 
    return option;
  });
}

function unselectChoiceLoadHashDeepClone(optionIndex, choiceIndex) {
  let newSelectedOptions = cloneDeep(selectedOptions);
  newSelectedOptions[optionIndex].choices[choiceIndex].isChosen = false;
  return newSelectedOptions;
}

function unselectChoiceImmutablityHelper(optionIndex, choiceIndex) {
  return update(selectedOptions, {
      [optionIndex]: {choices: {[choiceIndex]: {isChosen: {$set: false}}}}
  });
}

test('Given option 0 And choice 1 When unselecting with es6 spread operator and map Then should unselect option 0 choice 1', () => {
  const newSelectedOptions = unselectChoiceSpreadOperator(OPTION_INDEX, CHOICE_INDEX);

  expectOptionZeroChoice1ToNotBeChosen(newSelectedOptions);
});

test('Given option 0 And choice 1 When unselecting with deep clone Then should unselect option 0 choice 1', () => {
  const newSelectedOptions = unselectChoiceLoadHashDeepClone(OPTION_INDEX, CHOICE_INDEX);

  expectOptionZeroChoice1ToNotBeChosen(newSelectedOptions);
});

test('Given option 0 And choice 1 When unselecting with immutability-helper Then should unselect option 0 choice 1', () => {
  const newSelectedOptions = unselectChoiceImmutablityHelper(OPTION_INDEX, CHOICE_INDEX);

  expectOptionZeroChoice1ToNotBeChosen(newSelectedOptions);
});

function expectOptionZeroChoice1ToNotBeChosen(newSelectedOptions) {
  expect(newSelectedOptions[OPTION_INDEX].choices[CHOICE_INDEX].isChosen).toBe(false);
}