Skip adding preventDefault to onChange events in React Native

[jkomyno]

Bug

When using onChange in React Native, the users are faced with a couple possible error messages, as seen in #3153 and #3238.
This is due to the fact that it doesn't seem to be possible to properly extends React Native's event ( facebook/react-native#5507). My proposal is to skip adding .preventDefault to TextInput's onChange's event.

Tests

No test was broken

Eslint

Linting was respected

Closes #3153, closes #3238

[codecov-io]

Codecov Report

Merging #3460 into master will decrease coverage by 0.06%.
The diff coverage is 80%.

@@            Coverage Diff             @@
##           master    #3460      +/-   ##
==========================================
- Coverage     100%   99.93%   -0.07%     
==========================================
  Files          68       68              
  Lines        1531     1533       +2     
==========================================
+ Hits         1531     1532       +1     
- Misses          0        1       +1

Impacted Files	Coverage Δ
src/ConnectedField.js	98.94% <80%> (-1.06%)	⬇️

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[gustavohenke]

Reading thru facebook/react-native#5507, it seems like the solution is Object.defineProperty.
Only one user claimed to have issues with it. Have you tried using it?

And, even though no tests broke, the coverage decreased, what means at least one test should be written 😄

[jkomyno]

@gustavohenke Yep, I've already tried it, and with it I only achieved to delay the error: instead of appearing at the first change, it would appear at the second.
Also, I've tried the "lazy" way, described here, but calling event.preventDefault() from the app side wouldn't do anything (double checked with proper console.logs)

[jkomyno]

As per the tests, you're actually right, here's my plan.
The test should assert that in a RN environment the following snippet would throw:

onChange(
  {
    ...event,
    preventDefault: () => {
      defaultPrevented = true
      return eventPreventDefault(event)
    }
  },
  newValue,
  previousValue
)

My issue is that I have no idea on how to emulate RN's TextInput's event. Would you mind helping me with the test? @gustavohenke

[jkomyno]

@erikras this PR is used in production by me with no issues whatsoever, but unfortunately I wasn't able to create a test for this PR (to avoid codecov alerts).
Would you please know how to simulate a React Native Event class for a unit test?

[erikras]

Hmm... I'm seeing 100% code coverage when I run it locally. I'm going to merge and then fix any codecov problems later.

[jkomyno]

Thanks @erikras!

@AlimovSV the PR has been finally merged!

[AlimovSV]

Thanks @erikras, @jkomyno!

[erikras]

Published in v7.1.0.

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.