.babelrc

{
    "presets": ["@babel/preset-react"],
    "plugins": [
      "@babel/plugin-transform-runtime",
      [
        "@babel/plugin-proposal-class-properties",
        {
          "loose": true
        }
      ],
      "@babel/plugin-transform-react-inline-elements",
      "@babel/plugin-transform-react-constant-elements",
      "react-hot-loader/babel"
    ],
    "env": {
      "test":{
        "presets": ["@babel/preset-env", "@babel/preset-react"],
        "plugins": [
          "@babel/plugin-transform-runtime",
          [
            "@babel/plugin-proposal-class-properties",
            {
              "loose": true
            }
          ],
          "@babel/plugin-transform-react-inline-elements",
          "@babel/plugin-transform-react-constant-elements",
          "react-hot-loader/babel"
        ]
      }
    }
}