[ianschmitz]

Closes #8954.

We can ship the TypeScript template referencing @types/jest@25 until the 26 version drops. There should only be minor differences that we can call out in our release notes. From Simen:

main changes from 25 to 26 would be removal of require.requireActual, adding jest.useFakeTimers('modern') and adding jest.createMockFromModule()

Still todo:

• Figure out types migration path - we include @types/jest in the TypeScript template. We may require TypeScript 3.8: chore: require minimum typescript@3.8 jestjs/jest#9823. Need to sync with Simen to figure out the details

cc @SimenB.

Running into issues on Node 10.20.1 when running Jest.

While running in debug it's choking here: https://github.com/jsdom/jsdom/blob/8921128ee1efe6737e3ea200959eb01fe75ff3aa/lib/jsdom/browser/Window.js#L51, as jsGlobals includes globalThis which causes error:

    ReferenceError: globalThis is not defined

      at evalmachine.<anonymous>:1:1
      at setupWindow (node_modules/jsdom/lib/jsdom/browser/Window.js:51:55)
      at new Window (node_modules/jsdom/lib/jsdom/browser/Window.js:107:3)
      at exports.createWindow (node_modules/jsdom/lib/jsdom/browser/Window.js:38:10)
      at new JSDOM (node_modules/jsdom/lib/api.js:36:20)

Looks to be the same issue somebody else mentioned in the jsdom issues: jsdom/jsdom#2795 (comment)

I've created an issue in the jsdom repo to track this.

🎉

If it works - and I see the CI passes - then I think it's a good temporary fix!