How to use Carbon::setTestNow() in PHP?

Question

For testing purposes I want to set the date to a specific date. I'm now trying to do that using the Carbon lib, but it fails to do so:

Carbon::setTestNow(Carbon::createFromDate(2000, 1, 1));
printf(date("Y-m-d H:i:s"));  // prints 2018-06-28 13:21:06

What am I doing wrong here? How can I globally set the time to a specific date?

Answer 1

Setting

date() is a regular PHP function that doesn't have anything to do with Carbon and Carbon::setTestNow() does not change the system clock thus it's the expected behaviour.

I presume you just want to use Carbon all the way:

Carbon::setTestNow(Carbon::createFromDate(2000, 1, 1));
echo Carbon::now();                     

Resetting

(from @Orchis in notes)

Also worth noting that Carbon::setTestNow(); can be used to reset the time in Carbon to normal, so you don't affect later tests in your suite.