PostStylus

PostStylus is a PostCSS adapter for Stylus. It allows you to use any PostCSS plugin as a transparent Stylus plugin, and do custom post-processing of Stylus output.

It loads PostCSS processors into Stylus just before the output CSS is compiled to file.

Inspired by autoprefixer-stylus

Contents

• Install
• Usage
  • Gulp
  • Grunt
  • Webpack
  • CLI
• Passing Arguments to Plugins
• Custom Processing
• Warning Handler
• Asynchronous Processing

Install

$ npm install --save-dev poststylus

Usage

Use poststylus as a regular stylus plugin and pass it an array of PostCSS plugins you have installed, either as strings or functions.

stylus(css).use(poststylus([
  'autoprefixer',
  'rucksack-css'
]))

Gulp

var gulp = require('gulp'),
    stylus = require('gulp-stylus'),
    poststylus = require('poststylus'),
    autoprefixer = require('autoprefixer'),
    rucksack = require('rucksack-css');

gulp.task('stylus', function () {
  gulp.src('style.styl')
    .pipe(stylus({
      use: [
        poststylus([ autoprefixer, rucksack ])
      ]
    }))
    .pipe(gulp.dest('.'))
});

gulp.task('default', ['stylus']);

Grunt

grunt-contrib-stylus doesn't support passing arguments to plugins, so you have to wrap PostStylus in a function and return it

var postcss = function(){
  return require('poststylus')(['autoprefixer', 'rucksack-css']);
}

module.exports = function(grunt) {

  grunt.initConfig({

    stylus: {
      compile: {
        options: {
          use: [postcss]
        },
        files: {
          'style.css': 'style.styl'
        }
      }
    }

  });

  grunt.loadNpmTasks('grunt-contrib-stylus');

};

Webpack

Use stylus-loader with PostStylus as a plugin in your webpack.conf.js

var poststylus = require('poststylus'),
    webpack = require('webpack');

module: {
  loaders: [
    { test: /\.styl$/, loader: 'style-loader!css-loader!stylus-loader' }
  ]
},
stylus: {
  use: [
    poststylus([ 'autoprefixer', 'rucksack-css' ])
  ]
}

If you are using webpack 2, use LoaderOptionsPlugin to set options

module: {...},
plugins: [
  new webpack.LoaderOptionsPlugin({
    options: {
      stylus: {
        use: [poststylus([ 'autoprefixer', 'rucksack-css' ])]
      }
    }
  })
]

CLI

To use PostStylus on the Stylus CLI, pass poststylus to --use, and PostCSS plugins to --with:

$ stylus --use ./node_modules/poststylus --with "['autoprefixer']" --out test.css < test.styl

Passing Arguments to Plugins

If you need to pass arguments to a PostCSS plugin require() it and pass that function to PostStylus

var autoprefixer = require('autoprefixer');

stylus(css).use([
  poststylus([
    autoprefixer({ browsers: ['ie 8'] })
  ])
])

To pass arguments to PostCSS plugins on the CLI, you'll need to prefix require() with $PWD, since the stylus executable runs globally, while your plugins are (probably) installed locally:

stylus --use ./node_modules/poststylus --with "[require('${PWD}/node_modules/autoprefixer')({ browsers: ['ie 8'] })]" --out test.css < test.styl

Custom Processing

Do custom post-processing of Stylus output by declaring an on-the-fly PostCSS plugin

var myPostcss = postcss.plugin('custom', function() {
  return function (css) {
    // PostCSS processing here
  };
});

// Pipe it into poststylus
stylus(css).use(poststylus([myPostcss()]));

Refer to the [PostCSS Docs][postcss-link] for more on writing plugins.

Warning Handler

By default, if any of your PostCSS plugins raise a warning it will be displayed using console.error. You can override this behaviour by passing a function as the second argument to PostStylus.

stylus(css).use(poststylus([
    'autoprefixer',
    'rucksack-css'
], function(message) {
    console.info(message);
}));

Asynchronous Processing

Unfortunately the Stylus end event that PostStylus uses to pass back post-processed CSS doesn't accept a callback, so until this bug is patched upstream PostStylus cannot work with asynchronous PostCSS processing.

MIT © Sean King