babel/packages/babel-plugin-proposal-do-expressions/test/fixtures/do-expression-switch-case/fallthrough/output.js

const x = n => function () {
  switch (n) {
    case 0:
      'a';
    case 1:
      return 'b';
    case 2:
      return 'c';
    case 3:
      return void 0;
    case 4:
      'd';
      'e';
    default:
      return 'f';
  }
}();