old_contents: // Karma configuration
  module.exports = (config) => {
    config.set({
      basePath: __dirname,
      frameworks: ['mocha', 'sinon-chai'],
      files: [
        'source/**/*.spec.js',
  	  'tests/**/*.spec.js',
      ],
      exclude: [],
  
      preprocessors: {
        'source/**/*.js': ['webpack', 'sourcemap'],
        'tests/**/*.js': ['webpack', 'sourcemap'],
      },
      reporters: ['coverage', 'progress', 'coveralls'],
      coverageReporter: {
        type: 'lcov',
        dir: 'coverage/'
      },
      webpack: {
        resolve: {
          extensions: ['.js']
        },
        module: {
          loaders: [
            {
              test: /\.js$/,
              loader: 'babel-loader?plugins[]=istanbul',
            }
          ]
        },
        devtool: 'inline-source-map',
      },
      webpackMiddleware: {
        noInfo: true,
        stats: {
          chunks: false,
          colors: true
        },
        stats: 'errors-only'
      },
      plugins: [
        require('karma-webpack'),
        require('karma-coverage'),
        require('karma-coveralls'),
        require('karma-firefox-launcher'),
        require('karma-sourcemap-loader'),
        require('karma-mocha'),
        require('karma-sinon-chai'),
      ],
      port: 9876,
      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,
      browsers: ['Firefox'],
      //browsers: ['Chrome', 'IE', 'Firefox'],
      // Continuous Integration mode
      // if true, Karma captures browsers, runs the tests and exits
      singleRun: true
    });
  };
  
new_contents: // Karma configuration
  module.exports = (config) => {
    config.set({
      basePath: __dirname,
      frameworks: ['mocha', 'sinon-chai'],
      files: [
        'source/**/*.spec.js',
        'tests/**/*.spec.js',
      ],
      exclude: [],
  
      preprocessors: {
        'source/**/*.js': ['webpack', 'sourcemap'],
        'tests/**/*.js': ['webpack', 'sourcemap'],
      },
      reporters: ['coverage', 'progress', 'coveralls'],
      coverageReporter: {
        type: 'lcov',
        dir: 'coverage/'
      },
      webpack: {
        resolve: {
          extensions: ['.js']
        },
        module: {
          loaders: [
            {
              test: /\.js$/,
              loader: 'babel-loader?plugins[]=istanbul',
            }
          ]
        },
        devtool: 'inline-source-map',
      },
      webpackMiddleware: {
        noInfo: true,
        stats: {
          chunks: false,
          colors: true
        },
        stats: 'errors-only'
      },
      plugins: [
        require('karma-webpack'),
        require('karma-coverage'),
        require('karma-coveralls'),
        require('karma-firefox-launcher'),
        require('karma-sourcemap-loader'),
        require('karma-mocha'),
        require('karma-sinon-chai'),
      ],
      port: 9876,
      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,
      browsers: ['Firefox'],
      //browsers: ['Chrome', 'IE', 'Firefox'],
      // Continuous Integration mode
      // if true, Karma captures browsers, runs the tests and exits
      singleRun: true
    });
  };
  
subject: fix intendation