Problem with timezones in react native

[VictorPulzz]

Describe the bug
When I try convert date to select timezone, I got 'Invalid date'.
I know that we can use polyfill from this thread but it's look terrible.

console.log(dayjs('2023-07-11T10:00:00').tz('Australia/Melbourne').format('YYYY-MM-DD HH:mm'));
console.log(dayjs('2023-07-11T10:00:00').tz('Australia/Melbourne').utc().format('YYYY-MM-DD HH:mm'));

got:

Expected behavior
Timezone is working on react-native

Information

• Day.js Version [1.11.7]
• OS: MacOS m1
• React-native [0.71.8]
• Time zone: [not important]

[Willham12]

same issue here

[sam-houle1]

Same issue, @VictorPulzz @Willham12 did you guys found anything to fix this issue ?

[Willham12]

No, i'm still using momentjs

[VictorPulzz]

@sam-houle1 Unfortunately, without pollyfil, it doest work. You can try set offset monually like this:

// get offset use any date
const getOffset = dayjs.tz('2023-09-04 12:00:00', tz).utcOffset();
// set offset for any date
dayjs.utc(date).utcOffset(getOffset)

[badalsaibo]

@Willham12 Does momentjs not have timezones issue in React Native? If no, then I will be migrating.

[Willham12]

No issues with momentjs but it's deprecated.

[rklomp]

Same issue here. Switching back to momentjs for now :(

[alexkev]

I believe moment has the same issue: see this problem here: https://stackoverflow.com/questions/71421582/moment-returning-an-invalid-date-while-using-hermes-js-engine.

[alexkev]

This caused by hermes; follow this issue: facebook/hermes#865

[shuo-hiwintech]

I'm currently using moment and so far he's working fine.

[milesingrams]

We were dealing with this in our codebase and I was able to fix by patching a few lines of the dayjs/timezone plugin code. Here is the fix. Hopefully it can be merged!
#2843