date-fns格式无法正确格式化microSeconds？

Question

I am using the following script in order convert microSeconds in hh:mm using date-fns but I get the wrong formatting:

const microSeconds = 100000000 format(addMilliseconds(new Date(0), microSeconds / 1000), 'hh:mm')}

for example in this case I would need to get '00:01' but instead I get 01:01

Any idea how to fix it?

Runnable code https://stackblitz.com/edit/date-fns-playground-cdgduf

Answer 1

It's because date-fns format function relies on locales. Format's docs contains information (under table with accepted tokens):

The result may vary by locale.

You could subtract timezone offset:

const d = new Date(0);
const formatedValue = format(
   addMilliseconds(new Date(0 + d.getTimezoneOffset()*1000*60), microSeconds / 1000), 'HH:mm')

Change also date format to HH:mm , because hh is between 01 and 12

Answer 2

According to this example:

import { format } from 'date-fns';
const formatedValue = format(0, 'hh:mm')
// output: 01:00

You should not use date-fns to just convert a duration into a human-readable string since it always depends on timezones. You should implement your own format function since it's basic dividing and multiplying.

Working example => https://stackblitz.com/edit/date-fns-playground-whz5tg?file=app.ts