karma-browserify

A fast browserify integration for Karma that handles large projects with ease

karma-browserify

karma-browserify is a fast browserify integration for Karma that handles large projects with ease.

Get the plug-in via npm

npm install --save-dev karma-browserify

Add browserify as a framework to your Karma configuration file. For each file that should be processed and bundled by karma, configure the browserify preprocessor. Optionally use the browserify config entry to configure how the bundle gets created.

module.exports = function(karma) {
  karma.set({
 
    frameworks: [ 'browserify', 'jasmine', 'or', 'any', 'other', 'framework' ],
    files: ['test/**/*.js'],
    preprocessors: {
      'test/**/*.js': [ 'browserify' ]
    },
 
    browserify: {
      debug: true,
      transform: [ 'brfs' ]
    }
  });
}

Look at the example directory for a simple browserify + jasmine project that uses this plug-in.

Test bundles can be configured through the browserify karma configuration property. Configuration options are passed directly to browserify.

For example to generate source maps for easier debugging, specify:

    browserify: {
      debug: true
    }

There are three properties that are not passed directly:

If you use CoffeeScript, JSX or other tools that need to transform the source file before bundling, specify a browserify transform (karma preprocessors are not supported).

    browserify: {
      transform: [ 'reactify', 'coffeeify', 'brfs' ]
 
      // don't forget to register the extensions 
      extensions: ['.js', '.jsx', '.coffee']
    }

You can also specify options for the transformations:

    browserify: {
      transform: [ ['reactify', {'es6': true}], 'coffeeify', 'brfs' ]
    }

The browserify plugin option supports the same syntax as transform.

    browserify: {
      plugin: [ 'stringify' ]
    }

You may perform additional configuration in a function passed as the configure option and that receives the browserify instance as an argument. A custom prebundle event is emitted on the bundle right before a bundling operation takes place. This is useful when setting up things like externals:

    browserify: {
      configurefunction(bundle) {
        bundle.on('prebundle', function() {
          bundle.external('foobar');
        });
      }
    }

This project is a preprocessor for Karma that combines test files and dependencies into a browserified bundle. It relies on watchify to generate the bundle and to keep it updated during autoWatch=true.

Before the initial test run we build one browserify bundle for all test cases and dependencies. Once any of the files change, it incrementally updates the bundle. Each file included in karma is required from the file bundle via a stub. Thereby it ensures tests are only executed once per test run.

The following code snippet shows a Karma configuration file with all Bro related options.

module.exports = function(karma) {
  karma.set({
 
    // include browserify first in used frameworks 
    frameworks: [ 'browserify', 'jasmine' ],
 
    // add all your files here, 
    // including non-commonJS files you need to load before your test cases 
    files: [
      'some-non-cjs-library.js',
      'test/**/*.js'
    ],
 
    // add preprocessor to the files that should be 
    // processed via browserify 
    preprocessors: {
      'test/**/*.js': [ 'browserify' ]
    },
 
    // see what is going on 
    logLevel: 'LOG_DEBUG',
 
    // use autoWatch=true for quick and easy test re-execution once files change 
    autoWatch: true,
 
    // add additional browserify configuration properties here 
    // such as transform and/or debug=true to generate source maps 
    browserify: {
      debug: true,
      transform: [ 'brfs' ],
      configurefunction(bundle) {
        bundle.on('prebundle', function() {
          bundle.external('foobar');
        });
      }
    }
  });
};

Credit goes to to the original karma-browserify and karma-browserifast. This library builds on the lessons learned in these projects and offers improved configurability, speed and/or the ability to handle large projects.

MIT