gistfile1.txt

import merge from 'lodash/merge';

/* eslint-env mocha */

describe('new test', () => {
  it('works', () => {
    const getIt = (x = {}) => {
      const {
        a = null,
        b: {
          c = null,
          d = null,
        } = {},
      } = x;
      return {
        a,
        b: {
          c,
          d,
        },
      };
    };
    const getMore = (x = {}, got) => {
      const {
        b: {
          e = null,
        } = {},
      } = x;
      return {
        e,
        got,
      };
    };
    const merger = getter =>
      get => ({
        get: () => getter(get),
        merge: params =>
          merger(getter)(merge(get, params)),
        reGet: reGet =>
          merger(x => reGet(x, getter(x)))(get),
      });
    merger(getIt)()
      .merge({
        b: {
          d: 'd',
        },
      })
      .get()
      .should
      .eql({
        a: null,
        b: {
          c: null,
          d: 'd',
        },
      });
    merger(getIt)()
      .merge({
        b: {
          d: 'd',
        },
      })
      .merge({
        b: {
          c: 'c',
        },
      })
      .merge({
        a: 'a',
      })
      .merge({
        b: {
          d: 'dd',
        },
      })
      .get()
      .should
      .eql({
        a: 'a',
        b: {
          c: 'c',
          d: 'dd',
        },
      });
    merger(getIt)()
      .merge({
        a: 'a',
        b: {
          c: 'c',
          d: 'd',
        },
      })
      .reGet(getMore)
      .merge({
        b: {
          d: 'dd',
          e: 'e',
        },
      })
      .get()
      .should
      .eql({
        e: 'e',
        got: {
          a: 'a',
          b: {
            c: 'c',
            d: 'dd',
          },
        },
      });
  });
});