# @sigmacomputing/babel-plugin-lodash

A simple transform to cherry-pick Lodash modules so you don’t have to.

Combine with [lodash-webpack-plugin](https://www.npmjs.com/package/lodash-webpack-plugin)
for even smaller cherry-picked builds!

@sigmacomputing/babel-plugin-lodash is forked from
[babel-plugin-lodash](https://github.com/lodash/babel-plugin-lodash) which has
since been abandoned.

## Install

NPM

```shell
$ npm install --save lodash
$ npm install --save-dev babel-plugin-lodash @babel/cli @babel/preset-env
```

Yarn

```shell
$ yarn add lodash
$ yarn add @sigmacomputing/babel-plugin-lodash @babel/cli @babel/preset-env -D
```

## Example

Transforms

```js
import _ from 'lodash';
import { add } from 'lodash/fp';

const addOne = add(1);
_.map([1, 2, 3], addOne);
```

roughly to

```js
import _add from 'lodash/fp/add';
import _map from 'lodash/map';

const addOne = _add(1);
_map([1, 2, 3], addOne);
```

## Usage

###### .babelrc

```json
{
  "plugins": ["@sigmacomputing/babel-plugin-lodash"],
  "presets": [["@babel/env", { "targets": { "node": 6 } }]]
}
```

Set plugin options using an array of `[pluginName, optionsObject]`.

```json
{
  "plugins": [
    [
      "@sigmacomputing/babel-plugin-lodash",
      { "id": "lodash-compat", "cwd": "some/path" }
    ]
  ],
  "presets": [["@babel/env", { "targets": { "node": 6 } }]]
}
```

The `options.id` can be an array of ids.

```json
{
  "plugins": [
    ["@sigmacomputing/babel-plugin-lodash", { "id": ["async", "lodash-bound"] }]
  ],
  "presets": [["@babel/env", { "targets": { "node": 6 } }]]
}
```

###### Babel CLI

```sh
$ babel --plugins @sigmacomputing/babel-plugin-lodash --presets @babel/es2015 script.js
```

###### Babel API

```js
require('babel-core').transform('code', {
  plugins: ['@sigmacomputing/babel-plugin-lodash'],
  presets: [['@babel/env', { targets: { node: 6 } }]],
});
```

###### webpack.config.js

```js
'module': {
  'loaders': [{
    'loader': 'babel-loader',
    'test': /\.js$/,
    'exclude': /node_modules/,
    'query': {
      'plugins': ['@sigmacomputing/babel-plugin-lodash'],
      'presets': [['@babel/env', { 'targets': { 'node': 6 } }]]
    }
  }]
}
```

## FAQ

> Can this plugin produce ES2015 imports rather than CommonJS imports?

This plugin produces ES2015 imports by default. The
[`@babel/plugin-transform-modules-commonjs`](https://www.npmjs.com/package/@babel/plugin-transform-modules-commonjs)
plugin, which is included in the [`@babel/preset-es2015`](https://www.npmjs.com/package/@babel/preset-es2015)
preset, transforms ES2015 `import` statements to CommonJS. Omit it from your
preset to preserve ES2015 style imports.

## Limitations

- You must use ES2015 imports to load Lodash
- Babel < 6 & Node.js < 4 aren’t supported
- Chain sequences aren’t supported. See [this blog post](https://medium.com/making-internets/why-using-chain-is-a-mistake-9bc1f80d51ba) for alternatives.
- Modularized [method packages](https://www.npmjs.com/browse/keyword/lodash-modularized) aren’t supported