@breautek/merge-change/test/utils.get.spec.js

Simple library for deep merge of objects and other types (also for patch and immutable updates). Declarative operations to specific merge, for example to remove properties. Customize merging between specific types. Calculating diffs.

const utils = require('../utils.js');
const methods = require('../methods.js');

describe('Test get()', () => {

  test('get deep property', () => {
    const data = {
      prop: {
        deep: {
          superDeep: 'value',
        },
      },
    };
    const value = utils.get(data, '/prop/deep/superDeep', null, '/');
    expect(value).toEqual('value');
  });

  test('get array element', () => {
    const data = {
      items: [
        'value1',
        'value2',
      ],
    };
    const value = utils.get(data, 'items/1', null, '/');
    expect(value).toEqual('value2');
  });

  test('get if not exists or null', () => {
    const data = {
      prop: null,
    };
    expect(utils.get(data, '/prop/deep/superDeep', undefined, '/')).toEqual(undefined);
    expect(utils.get(data, '/prop2/superDeep', undefined, '/')).toEqual(undefined);
  });

  test('get from custom object', () => {
    class Custom {
      constructor(value = {}) {
        this.value = value;
      }
      [methods.toOperation](){
        return this.value;
      }
    }

    let data = new Custom({
      name: 'Test',
      sub: {
        prop: {
          inner: 100,
        },
      },
    });

    const value = utils.get(data, 'sub.prop.inner', null, '.');
    expect(value).toEqual(100);
  });

});