diff --git a/packages/jest-util/src/create_process_object.js b/packages/jest-util/src/create_process_object.js index a7442f1ec19d..fc96bf161f82 100644 --- a/packages/jest-util/src/create_process_object.js +++ b/packages/jest-util/src/create_process_object.js @@ -17,6 +17,10 @@ const BLACKLIST = new Set(['env', 'mainModule', '_events']); // mimic it (see https://nodejs.org/api/process.html#process_process_env). function createProcessEnv() { + if (typeof Proxy === 'undefined') { + return deepCyclicCopy(process.env); + } + // $FlowFixMe: Apparently Flow does not understand that this is a prototype. const proto: Object = Object.getPrototypeOf(process.env); const real = Object.create(proto);