You can use ...state, action
instead of Object.assign({}, state, action)
Will need a separate Babel plugin to work.
1npm i -D babel-plugin-syntax-object-rest-spread babel-plugin-transform-object-rest-spread
once installed, add the plugins to .babelrc
1"plugins": [
2 "syntax-object-rest-spread",
3 "transform-object-rest-spread"
4 ]