.babelrc

{
  "presets": [
    [
      "env",
      {
        "debug": false,
        "modules": false,
        "targets": {
          "browsers": [
            "> 1%",
            "last 3 versions",
            "ios > 8",
            "ie > 9",
            "not ie < 10"
          ]
        },
        "useBuiltIns": true
      }
    ],
    "stage-3"
  ],
  "plugins": [
    [
      "transform-runtime",
      {
        "helpers": false,
        "polyfill": false,
        "regenerator": true
      }
    ],
    "transform-class-properties"
  ],
  "env": {
    "test": {
      "presets": [
        [
          "env",
          {
            "debug": false,
            "modules": "commonjs",
            "targets": {
              "node": "current"
            },
            "useBuiltIns": true
          }
        ],
        "stage-3"
      ],
      "plugins": [
        [
          "transform-runtime",
          {
            "helpers": false,
            "polyfill": false,
            "regenerator": true
          }
        ],
        "transform-class-properties"
      ]
    }
  }
}