Awesome

xo-loader

XO loader for webpack. Based on eslint-loader

Install

$ npm install xo-loader --save-dev

Usage

In your webpack configuration

module.exports = {
	// ...
	module: {
		loaders: [
			{test: /\.js$/, loader: 'xo-loader', exclude: /node_modules/}
		]
	}
	// ...
}

When using with transpiling loaders (like babel-loader), make sure they are in correct order (bottom to top). Otherwise files will be check after being processed by babel-loader

module.exports = {
	// ...
	module: {
		loaders: [
			{test: /\.js$/, loader: 'babel-loader', exclude: /node_modules/},
			{test: /\.js$/, loader: 'xo-loader', exclude: /node_modules/}
		]
	}
	// ...
}

To be safe, you can use preLoaders section to check source files, not modified by other loaders (like babel-loader)

module.exports = {
	// ...
	module: {
		preLoaders: [
			{test: /\.js$/, loader: 'xo-loader', exclude: /node_modules/}
		]
	}
	// ...
}

webpack@2.1.0-beta.23 and up

As of latest release notes, preLoaders and postLoaders have been deprecated in favor of enforce: 'pre' or enforce: 'post'. Also custom properties are not allowed, and can be supplied through webpack.LoaderOptionsPlugin({}).

module.exports = {
	// ...
	module: {
		loaders [
			{test: /\.js$/, enforce:'pre', loader: 'xo-loader', exclude: /node_modules/}
		]
	},
	plugins: [
		new webpack.LoaderOptionsPlugin({
			options: {
				xo: {
					emitError: true
				}
			}
		})
	]
	// ...	
}

Options

You can pass XO options directly by

• Adding a query string to the loader for this loader usabe only

{
	module: {
		preLoaders: [
			{
				test: /\.js$/,
				loader: 'xo-loader?{rules:[{semi:0}]}',
				exclude: /node_modules/,
			},
		],
	},
}

• Adding an xo entry in your webpack config for global options:

module.exports = {
	xo: {
		space: true
	}
}

Note that you can use both method in order to benefit from global & specific options

Errors and Warning

By default the loader will auto adjust error reporting depending on xo errors/warnings counts. You can still force this behavior by using emitError or emitWarning options:

emitError (default: false)

Loader will always return errors if this option is set to true.

module.exports = {
	entry: "...",
	module: {
		// ...
	}
	xo: {
		emitError: true
	}
}

emitWarning (default: false)

Loader will always return warnings if option is set to true.

failOnWarning (default: false)

Loader will cause the module build to fail if there are any xo warnings.

module.exports = {
	entry: "...",
	module: {
		// ...
	}
	xo: {
		failOnWarning: true
	}
}

failOnError (default: false)

Loader will cause the module build to fail if there are any xo errors.

module.exports = {
	entry: "...",
	module: {
		// ...
	}
	xo: {
		failOnError: true
	}
}

Changelog

License