.babelrc

{
    "presets": [
        [
            "@babel/preset-env",
            {
                "modules": false,
                "targets": {
                    "browsers": [
                        "last 2 Chrome versions",
                        "last 2 Firefox versions",
                        "last 2 Safari versions",
                        "last 2 iOS versions",
                        "last 1 Android version",
                        "last 1 ChromeAndroid version",
                        "ie 11"
                    ]
                }
            }
        ],
        "@babel/preset-react"
    ],
    "plugins": [
        "@babel/plugin-proposal-class-properties",
        "@babel/plugin-transform-modules-commonjs"
    ],
"env": {
    "test": {
      "plugins": ["@babel/plugin-transform-runtime"]
    }
  }
}