function getBabelPresetEnv()

in dev-utils/build.js [69:117]

• 29 lines of code
• 5 McCabe index (conditional complexity)

function getBabelPresetEnv(bundleType) {
  const isBrowser = [
    BROWSER_DEV,
    BROWSER_PROD,
    BROWSER_ESM_PROD,
    BROWSER_ESM_ES2015
  ].includes(bundleType)
  /**
   * Decides transformation of ES6 module syntax to another module type.
   */
  const shipESModule = [
    NODE_ESM_PROD,
    BROWSER_ESM_PROD,
    BROWSER_ESM_ES2015
  ].includes(bundleType)

  /**
   * By default RUM agent support starts from IE 11 and we do not want every users to run
   * babel on thier dependencies to support older browser versions. However,
   * advanced users can always use webpack resolve.mainFields set to `source`
   * and target their audience.
   */
  let targets = { ie: '11' }
  /**
   * Angular CLI uses the target `es2015` by default which is based on the
   * Angular Packaging Format specification and uses it for differential
   * loading (module/nomodule)
   * Info - https://angular.io/guide/deployment#configuring-differential-loading
   *
   * Babel already supports browsers targetting ES Modules via `esmodules` flag
   * https://babeljs.io/docs/en/babel-preset-env#targetsesmodules
   */
  if (isBrowser && bundleType === BROWSER_ESM_ES2015) {
    targets = { esmodules: true }
  } else if (!isBrowser) {
    targets = { node: true }
  }

  return [
    [
      '@babel/preset-env',
      {
        targets,
        modules: shipESModule ? false : 'auto',
        loose: true
      }
    ]
  ]
}