babel-plugin-split-import

Why?

When adding code splitting to our app we ran into the problem where recompile time while working in development was too slow. We found that the code splitting using dynamic imports was slowing it down. This plugin's goal is to transform imports to use code-splitting only in production so dev times are still fast.

Usage

yarn add babel-plugin-split-import --dev

Via .babelrc or babel-loader.

{
  "plugins": [["split-import", options]]
}

options

options can be object.

{
  "forcesplit": true // default false
}

Configuration

By default, babel-plugin-split-import won't use code-splitting. Code splitting can be enabled through the FORCE_SPLIT command line variable or the forceSplit babel plugin option.

If you are using eslint, you will likely want to add simport as a global variable.

In JavaScript Code

The first step is to set the function that returns a component given a loader via the simport.setSplitLoader function. This should be called before simport is used anywhere. Afterwards, call simport with the path to the imported component.

Example

import Loadable from "react-loadable";
 
function makeLoadableComponent(loader) {
  return Loadable({
    loader
  });
}
 
simport.setSplitLoader(makeLoadableComponent);
 
const MyComponent = simport("./path/to/MyComponent");

If the plugin is configured to use code splitting, then the code will compile to:

const MyComponent = makeLoadableComponent(() => import("./path/to/MyComponent"));

Otherwise, the code will compile to:

import MyComponent from "./path/to/MyComponent"