lodashのmergeは破壊的

import * as _ from 'lodash';

const data1 = {advertiser: 'GOOGLE', agency: 'GOOGLE 1', division: 'hoge'};
const data2 = {advertiser: 'APPLE', agency: 'APPLE 1', division: 'anim', telito: 'jikken'};

const res = _.merge(data1, data2);

console.log(data1);
console.log(data2);
console.log(res);

・ログ data1

{ advertiser: 'APPLE',
  agency: 'APPLE 1',
  division: 'anim',
  telito: 'jikken' }

data2

{ advertiser: 'APPLE',
  agency: 'APPLE 1',
  division: 'anim',
  telito: 'jikken' }

res

{ advertiser: 'APPLE',
  agency: 'APPLE 1',
  division: 'anim',
  telito: 'jikken' }

data1は破壊されてる。 ただし、もともとあるキーは保持。

結果はdata1と同じ