References for Jest that are not packaged by default to solve the, `ReferenceError: Request is not defined` error.
npm install jest-fix-undefined
References for Jest that are not packaged by default to solve the, "ReferenceError: Request is not defined" error.
If you have a Typescript project (have not tested on Javascript, same problem may exist) that uses Jest and you try to use the following objects in your test functions:
* Nodejs Request
* Nodejs Response
* Nodejs Headers
You will receive an error message from Jest: ReferenceError: Request is not defined.
According to this Jest issue, this is a known limitation of Jest that you need to fix yourself. After reading this issue, this gave me some ideas on a fix for the Jest error message about _____ is not defined.
Personally, I am not a fan of randomly importing a npm module as a hack to fix issues. I knew that I would see this code, import 'isomorphic-fetch', in my Jest tests sometime in the future and wonder what on Earth that was there for. Also, adding isomorphic-fetch would cause bloat when I only need it for some references.
So instead, I decided to create my own hack. Create a repo dedicated to fixing this Jest undefined issue. A repo that is dedicated to fixing this issue while staying as slim as possible.
* npm install --save-dev jest-fix-undefined
* Then, add import "jest-fix-undefined" to the top of your Jest test files.
* The "ReferenceError: _______ is not defined" error should now be gone when running tests!
* Levi Bostian - GitHub, Twitter, Website/blog
jest-fix-undefined is open for pull requests. Check out the list of issues for tasks I am planning on working on. Check them out if you wish to contribute in that way.
Want to add to jest-fix-undefined? Before you decide to take a bunch of time and add functionality to the module, please, create an issue stating what you wish to add. This might save you some time in case your purpose does not fit well in the use cases of jest-fix-undefined.
If you find more types that throw ReferenceError by Jest, feel free to add them to this library and create a pull request! In order to make a pull request, you must add tests showing that ReferenceError is indeed thrown by Jest when trying to use it and that by using this library, it is fixed.
jest-fix-undefined is available under the MIT license. See the LICENSE file for more info.