generator-babel-boilerplate

A Yeoman generator to author libraries in ES2015 (and beyond!) for Node and the browser.

Features

• Author in ES2015 (even the unit tests)
• Export as ES5 & UMD
• Mocha-Chai-Sinon testing stack
• Unit tests that work in Node and in the browser

Installation

Install yo and this generator globally.

npm install -g yo generator-babel-boilerplate

Using Yeoman

Navigate to the directory you'd like to use for your project, then run yo babel-boilerplate.

Answer a few questions, and your project will be scaffolded.

Basic Guide

Write your code in src. The entry file is what you named the project in kebab case (although the filename can be changed).

Run npm run build to compile the source into a distributable format.

Put your unit tests in test/unit. The npm test command runs the tests using Node. If your library / tests require the DOM API, see the test/setup/node.js file.

npm Scripts

• npm test - Lint the library and tests, then run the unit tests
• npm run lint - Lint the source and unit tests
• npm run watch - Continuously run the unit tests as you make changes to the source and test files themselves
• npm run test-browser - Build the library for use with the browser spec runner. Changes to the source will cause the runner to automatically refresh.
• npm run build - Lint then build the library
• npm run coverage - Generate a coverage report

Browser Tests

The browser spec runner can be opened in a browser to run your tests. For it to work, you must first run npm run test-browser. This will set up a watch task that will automatically refresh the tests when your scripts, or the tests, change.

Code Climate

This library is set up to integrate with Code Climate. If you've never used Code Climate, then you might be wondering why it's useful. There are two reasons:

1. It consumes code coverage reports, and provides a coverage badge for the README
2. It provides interesting stats on your library, if you're into that kinda thing

Either of these items on the list can simply be ignored if you're uninterested in them. Or you can pull Code Climate out entirely from the boilerplate and not worry about it. To do that, update the relevant Gulp tasks and the Travis build.

If you'd like to set up Code Climate for your project, follow the steps here.

Linting

This boilerplate uses ESLint and JSCS to lint your source. To change the rules, edit the .eslintrc and .jscsrc files in the root directory, respectively.

Given that your unit tests aren't your library code, it makes sense to lint them against a separate ESLint configuration. For this reason, a separate, unit-test specific .eslintrc can be found in the test directory. Unlike ESLint, the same JSCS rules are applied to both your code and your tests.

FAQ

What Babel features are supported?

Nearly all Babel features should be supported by this boilerplate. If you find a feature that is throwing an error when you use it, follow these steps:

1. Double check to make sure that you're not typoing the new syntax ;)
2. Determine what task is failing (for instance, is it JSCS?)
3. Check that project's issue tracker to see if it is a known issue
4. If it isn't, then open an issue here

Because of the fact that dependencies of this boilerplate, such as JSCS, are maintained by a team separate from Babel, there may be a delay between when a new feature is added to Babel and when those other libraries add support for it.

When should I consider using this boilerplate?

You're authoring any library that exports a single file. From small libraries to full-fledged JavaScript web apps, I use this generator for both.

When might I not want to use this boilerplate?

You can always use this boilerplate as inspiration, but it works best for smaller libraries. If you're building a full-scale webapp, you will likely need to make more changes to the build system. This is because the boilerplate only deals with JavaScript; common build tasks like CSS preprocessing, image minification, or HTML template building are intentionally omitted from this boilerplate.

There are so many different preferences and needs when it comes to building a webapp, it wouldn't make sense to pick any one configuration for this boilerplate.

Luckily, it's relatively straightforward to add those things to the boilerplate on a per-project basis.

What's the browser compatibility?

As a rule of thumb, Babel works best in IE9 and above.

Are there examples?

Quite a few. Check them out on the wiki.

Is there a version for Node-only projects?

There is, though I wouldn't recommend using it. It's unmaintained, and Node is rapidly adding support for ES2015 features as of v4. Before you decide to transpile your Node code, double-check to make sure that it isn't already supported.

With that said, you can still check out the project over here.

Customizing

This boilerplate is, to a degree, customizable. To make changes, find what you're looking to do below and follow the instructions.

I want to change the primary source file

The primary source file for the library is src/index.js. Only the files that this file imports will be included in the final build. To change the name of this entry file:

1. Rename the file
2. Update the value of entryFileName in package.json under babelBoilerplateOptions

I want to change the destination file name or directory

1. Update main in package.json

I want to change what variable my module exports

MyLibrary is the name of the variable exported from this boilerplate. You can change this by following these steps:

1. Ensure that the variable you're exporting exists in your scripts
2. Update the value of exportVarName in package.json under babelBoilerplateOptions
3. Check that the unit tests have been updated to reference the new value

I don't want to export a variable

When prompted for the name of the library's main variable, leave the response empty.

My library depends on an external module

In the simplest case, you just need to install the module and use it in your scripts.

If you want to access the module itself in your unit test files, you will need to set up the test environment to support the module. To do this:

1. Load the module in the test setup file.
2. Add any imported variables to globals object in the test globals JSON.