concat-merge

Recursively merge objects, especially for webpack/rollup configs.

Comparison

| name | immutable | concat | dedupe | clone | multiple parameters | recommended | | ----------------------------------------------------------------------------------------------------------------------------------------------------------- | --------- | ---------------- | ---------------- | ---------------- | ------------------- | ----------- | | concat-merge | true | true | false | true | no | yes | | merge-deep | true | true | true | true | yes | yes | | deepmerge | true | true | false | false (option) | no | | | lodash/merge | false | false | false | true | yes | | | lodash/mergeWith | false | false (option) | false (option) | true | yes | yes |

Install

npm install concat-merge

Usage

import concatMerge from 'concat-merge'

concatMerge(baseConfig, {
  input: 'entry.js',
  plugins: [inject({React: 'react'})],
})

lodash equivalent:

import mergeWith from 'lodash/mergeWith'

const concatMerge = (...args) =>
  mergeWith({}, ...args, (prev, next) => {
    if (Array.isArray(prev)) {
      return prev.concat(next)
    }
  })