How to use this plugin with karma?

[geekyme]

my config:

module.exports = function(config) {
  config.set({

    // base path that will be used to resolve all patterns (eg. files, exclude)
    basePath: '',


    // frameworks to use
    // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
    frameworks: ['jasmine'],


    // list of files / patterns to load in the browser
    files: [
      // we use this pattern to load test files
      // see https://github.com/webpack/karma-webpack/issues/23
      'tests/tests_index.js'
    ],


    // list of files to exclude
    exclude: [
    ],


    // preprocess matching files before serving them to the browser
    // available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
    preprocessors: {
        'tests/tests_index.js': [ 'webpack', 'sourcemap' ]
    },

    webpack: { 
      devtool: 'cheap-source-map', 
      module: {
        loaders: [
          { test: /\.js$/, exclude: /node_modules/, loaders: ["babel?plugins=babel-plugin-rewire"] } // loaders can take parameters as a querystring
        ]
      }
    },

    webpackServer: {
      noInfo: true //please don't spam the console when running in karma!
    },


    // test results reporter to use
    // possible values: 'dots', 'progress'
    // available reporters: https://npmjs.org/browse/keyword/karma-reporter
    reporters: ['dots','html'],


    // web server port
    port: 9876,


    // enable / disable colors in the output (reporters and logs)
    colors: true,


    // level of logging
    // possible values: config.LOG_DISABLE || config.LOG_ERROR || config.LOG_WARN || config.LOG_INFO || config.LOG_DEBUG
    logLevel: config.LOG_INFO,


    // enable / disable watching file and executing tests whenever any file changes
    autoWatch: true,


    // start these browsers
    // available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
    browsers: ['Chrome'],


    // Continuous Integration mode
    // if true, Karma captures browsers, runs the tests and exits
    singleRun: false,

  });
};

when i do that, then i get the following error:

  Uncaught TypeError: Object.assign is not a function
  at /blah/tests/tests_index.js:953

The error goes away if i remove plugins=babel-plugin-rewire from loaders: ["babel?plugins=babel-plugin-rewire"]

[geekyme]

Turns out I had to enable babel runtime http://babeljs.io/docs/usage/runtime/. might want to document that in readme. :)

[Jpunt]

@geekyme: Where and how did you enable the babel runtime?

[longfin]

@Jpunt https://github.com/babel/babel-loader#babel-is-injecting-helpers-into-each-file-and-bloating-my-code

[Jpunt]

thanks!