old_contents: module.exports = function karma(config) {
    config.set({
      frameworks: ['mocha'],
      files: [
        { pattern: 'src/**/*.js', included: false },
        'tests/**/*.js',
      ],
      preprocessors: {
        'tests/**/*.js': ['webpack', 'sourcemap'],
      },
      webpack: {
        module: {
          loaders: [
            {
              test: /\.js$/,
              exclude: /node_modules/,
              loader: 'babel-loader',
              query: {
                presets: [
                  ['env', {
                    targets: {
                      edge: 12,
                      firefox: 42,
                      chrome: 49,
                      safari: 10,
                      node: 6,
                    },
                    modules: false,
                  }],
                ],
                plugins: ['transform-object-rest-spread'],
              },
            },
          ],
        },
        devtool: 'inline-source-map',
      },
      webpackMiddleware: {
        noInfo: 'true',
      },
      reporters: ['mocha'],
      logLevel: config.LOG_WARN,
      browsers: [process.env.TRAVIS ? 'Chrome_travis_ci' : 'Chrome', 'Firefox'],
      customLaunchers: {
        Chrome_travis_ci: {
          base: 'Chrome',
          flags: ['--no-sandbox'],
        },
      },
    });
  };
  
new_contents: module.exports = function karma(config) {
    config.set({
      frameworks: ['mocha'],
      files: [
        { pattern: 'src/**/*.js', included: false },
        'tests/**/*.js',
      ],
      preprocessors: {
        'tests/**/*.js': ['webpack', 'sourcemap'],
      },
      webpack: {
        module: {
          loaders: [
            {
              test: /\.js$/,
              exclude: /node_modules/,
              loader: 'babel-loader',
              query: {
                presets: [
                  ['env', {
                    targets: {
                      edge: 12,
                      firefox: 42,
                      chrome: 49,
                      safari: 10,
                      node: 6,
                    },
                    modules: false,
                  }],
                ],
                plugins: ['transform-object-rest-spread'],
              },
            },
          ],
        },
        devtool: 'inline-source-map',
      },
      webpackMiddleware: {
        noInfo: 'true',
      },
      reporters: ['mocha'],
      logLevel: config.LOG_WARN,
      browsers: [process.env.TRAVIS ? 'Chrome_travis_ci' : 'Chrome', 'Firefox'],
      customLaunchers: {
        Chrome_travis_ci: {
          base: 'Chrome',
          flags: ['--no-sandbox'],
        },
      },
      singleRun: process.env.TRAVIS,
    });
  };
  
subject: Change the singleRun Karma option to true for Travis builds