@atom/babel7-transpiler

atom-babel7-transpiler

This project implements an Atom package transpiler that transpiles your package's files with Babel 7.

Usage

1. Install the package
2. Add an atomTranspilers entry to your package.json
3. Install Babel presets and plugins, and configure Babel as you wish

In detail:

1. First, install the package from the npm registry:

npm install --save @atom/babel7-transpiler

2. Next, modify your package.json to include a reference to the transpiler for any files you want Babel to process as described in the Atom Flight Manual. For example, to process every file ending in .js in your package, you could use:

{
  ...
  "atomTranspilers": [
    {
      "glob": "**/*.js",
      "transpiler": "@atom/babel7-transpiler"
    }
  ]
}

3. Finally, install Babel and all the presets and plugins you want to use as normal. For a simple example, if you wanted to use the ES2015 and React presets, you might run:

npm install --save babel-preset-env babel-preset-react

and then create a .babelrc file to configure Babel to use them:

{
  "presets": ["env", "react"]
}

You may also specify options in your package.json inside the optional options object; the subkey babel, if it exists, will be passed as options to babel.transformSync. Note that if you don't want Babel to search up the directory hierarchy for a .babelrc file, you need to add the "babelrc": false option to the settings. Otherwise Babel may mistakenly use a user's .babelrc from elsewhere on the filesystem when trying to build your package.

{
  // ...
  "atomTranspilers": [
    {
      "glob": "**/*.js",
      "transpiler": "@atom/babel7-transpiler",
      "options": {
        "babel": {
          "presets": ["es2015", "react"],
          "babelrc": false
        }
      }
    }
  ]
}

Options

You may specify the following options as values of the options object in your package.json:

Option	Default	Description
setBabelEnv	false, true or a string	Sets the BABEL_ENV environment variable. When true, sets it to "development" when atom.inDevMode() or atom.inSpecMode() is true and "production" otherwise. When given as a string, uses the value of the environment variable of that name instead. The feature returns BABEL_ENV to its prior value after transpilation finishes.
babel	{}	Options to pass as the second argument to babel.transform (the same options you can put in a .babelrc).
cacheKeyFiles	[]	An array of files to include when determining whether or not to use the cache. For example, to force a recompile anytime your .babelrc changes, add .babelrc to this array.

Other Details

Source Maps

To enable source maps within Atom, set the Babel sourceMaps option to "inline" in your Babel configuration.

Babel Environment

Babel supports an option called env that allows you to configure Babel on a per-environment basis. The Babel environment is controlled via an environment variable called BABEL_ENV; this module automatically sets the environment variable to "development" if Atom is in dev mode (atom.inDevMode() returns true) and "production" otherwise.