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activeElement might change during userEvent.type causing runtime errors

See original GitHub issue

@testing-library/user-event version: >= 11.1.0
@testing-library/dom version: 5.10.1
Testing Framework and version: jest@26.0.1
DOM Environment: jsdom jest-environment-jsdom-global@2.0.2
node: 13.7.0

What you did:

Using userEvent.type. We have like > 1k tests which mostly use fireEvent but slowly upgrading to userEvent. All run fine, execept for one I encountered while updating our dependencies.

As a tmp fix one can use fireEvent.change.

What happened:

I narrowed it down to start with the release of https://github.com/testing-library/user-event/releases/tag/v11.1.0

    TypeError: Cannot read property 'length' of undefined

      at calculateNewValue (node_modules/@testing-library/user-event/dist/type.js:312:43)
      at typeCharacter (node_modules/@testing-library/user-event/dist/type.js:366:43)
      at typeImpl (node_modules/@testing-library/user-event/dist/type.js:230:29)
      at node_modules/@testing-library/user-event/dist/type.js:20:14
      at node_modules/@testing-library/react/dist/pure.js:58:16

Reproduction:

Problem description:

We currently have 90 occurrences for await userEvent.type( in our codebase, yet only a single one has this issue. I don’t understand (yet) what could cause this. But I figured out the activeElement is always the body, so calling currentValue() will be undefined, as body has no value prop.

I will provide more details if I find more.

Issue Analytics

State:
Created 3 years ago
Comments:6 (1 by maintainers)

Top GitHub Comments

8reactions

Junhao6503commented, Sep 16, 2020

I am still encountering this issue due to portals. It gives me errors like:

TypeError: Cannot read property 'length' of undefined
      at setSelectionRange (node_modules/@testing-library/user-event/dist/type.js:240:70)
      at fireInputEventIfNeeded (node_modules/@testing-library/user-event/dist/type.js:269:5)
      at handleDel (node_modules/@testing-library/user-event/dist/type.js:613:5)
      at node_modules/@testing-library/user-event/dist/type.js:144:29
      at typeImpl (node_modules/@testing-library/user-event/dist/type.js:159:4)
      at type (node_modules/@testing-library/user-event/dist/type.js:73:14)
      at Object.clear (node_modules/@testing-library/user-event/dist/clear.js:26:18)
      at Object.<anonymous> (src/__tests__/UserProfile/UserProfileEdit.test.js:148:17)

1reaction

tsmithATXcommented, Jul 30, 2020

v12.0.14 addressed our issues, no longer seeing this happen!

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