First time trying to use jest

So I'm trying to run jest for the first time in my project and I'm running into some confusing error.

I get path/config/polyfills.js: Property object of MemberExpression expected node to be of a type ["Expression"] but instead got null when I run npm test and my script looks like this: "test": "jest".

Here is also my polyfills.js:

'use strict';

if (typeof Promise === 'undefined') {
  // Rejection tracking prevents a common issue where React gets into an
  // inconsistent state due to an error, but it gets swallowed by a Promise,
  // and the user has no idea what causes React's erratic future behavior.
  require('promise/lib/rejection-tracking').enable();
  window.Promise = require('promise/lib/es6-extensions.js');
}

// fetch() polyfill for making API calls.
require('whatwg-fetch');

// Object.assign() is commonly used with React.
// It will use the native implementation if it's present and isn't buggy.
Object.assign = require('object-assign');

// In tests, polyfill requestAnimationFrame since jsdom doesn't provide it yet.
// We don't polyfill it in the browser--this is user's responsibility.
if (process.env.NODE_ENV === 'test') {
  require('raf').polyfill(global);
}

This is my first time using jest and I didn't use create-react-app to set up my application so a lot of the jest guides I've been looking at haven't been very helpful. Thanks for your help in advance!