Wrong type declaration in the onChange event

Bug report

Summary

The Event received as the argument for the onChange callback has an incorrect type declared. The type should be event.nativeEvent.timestamp but the actual type declared is evt.nativeEvent.timeStamp. Note the uppercase S in timeStamp

This is not a problem since I can do what I need using the second argument on the onChange callback or even using event.nativeEvent.timestamp and disregarding the linter. Anyways, I thought maintainers would like to know this is happening. Hopefully it should be an easy fix for someone familiar with React Native types.

Reproducible sample code

This shows a linting error:

<DateTimePicker
  value={new Date()}
  mode='date'
  is24Hour={false}
  display='default'
  onChange={evt => {
    const timestamp = evt.nativeEvent.timestamp
    if (timestamp) {
      // handle the input change
    }
  }}
/>

Steps to reproduce

Using the code above the linter will complain and suggest to use evt.nativeEvent.timeStamp instead.

Describe what you expected to happen: I expected timeStamp to be the property with the value, but it was timestamp. The result was that timestamp in the code above was always undefined

Hovering over event.nativeEvent shows the following type:

React.BaseSyntheticEvent<Event, EventTarget & Readonly<{ timestamp: number; }>, EventTarget>.nativeEvent: Event

I was hoping the Readonly<{timestamp: number;}> part should fix this, but I’ve been using typescript for just a few days and I don’t really know what’s going on there

Environment info

npx react-native info output:

System:
    OS: macOS 10.15.5
    CPU: (4) x64 Intel(R) Core(TM) i5-6360U CPU @ 2.00GHz
    Memory: 32.04 MB / 8.00 GB
    Shell: 5.7.1 - /bin/zsh
  Binaries:
    Node: 12.16.1 - /usr/local/bin/node
    Yarn: 1.3.2 - /usr/local/bin/yarn
    npm: 6.13.4 - /usr/local/bin/npm
    Watchman: 4.7.0 - /usr/local/bin/watchman
  Managers:
    CocoaPods: 1.10.0 - /usr/local/bin/pod
  SDKs:
    iOS SDK: Not Found
    Android SDK:
      API Levels: 23, 24, 26, 29
      Build Tools: 23.0.1, 26.0.1, 26.0.2, 28.0.3, 29.0.2
      Android NDK: Not Found
  IDEs:
    Android Studio: Not Found
    Xcode: /undefined - /usr/bin/xcodebuild
  Languages:
    Java: 1.8.0_141 - /usr/bin/javac
    Python: 2.7.16 - /usr/bin/python
  npmPackages:
    @react-native-community/cli: Not Found
    react: 16.13.1 => 16.13.1
    react-native: ~0.63.3 => 0.63.3
    react-native-macos: Not Found
  npmGlobalPackages:
    *react-native*: Not Found

datetimepicker version: ^3.0.8

iOS / Android version: Android 11

[lexicalninja]

import RNDateTimePicker, { AndroidEvent, Event } from '@react-native-community/datetimepicker'
.....

 onChange={(event: Event | AndroidEvent, date?: Date): void => {
     ...
})

This is how I got it to work if it helps

[vonovak]

as of v6, this would look like this:

import RNDateTimePicker, { DateTimePickerEvent } from '@react-native-community/datetimepicker'
...

 onChange={(event: DateTimePickerEvent, date?: Date): void => {
     ...
})