It's not os dependent. I thinks problem is for V8 or js engine somthing. same output on node.js

What is test_date here?

It's normal date object:
var test_date = new Date(Date.UTC(2018, 1, 1, 0, 0, 0, 0));

on my tests is :
https://github.com/mhf-ir/intl-browser-test/blob/master/views/index.pug#L14

README.md updated

any update

I tracked this down to the commit between 69.0.3487.1 and 69.0.3488.0 which upgraded the ICU dependency to the 62.1 version, reviewed here:

 https://chromium-review.googlesource.com/c/chromium/src/+/1111818

As you can see from the commit comment, it says:

 > Arabic number format expected results are also updated because Arabic
 > locales now use "European" digits by default in Chromium's ICU to match
 > the behavior of other Google products

so it seems that this was a deliberate change to the default behaviour.

You can override this default by using the unicode extension to the locale tag, as described here:

 https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DateTimeFormat

Specifically, you can override the numbering system used by using locale "ar-u-nu-arab" (the extra parts mean unicode extension, numbering system: arabic).

There are also some specific Arabic sub-locales which default to using arabic numerals, such as "ar-EG", but it's probably safer to use the unicode extension override, to avoid the default changing in the future for the Egyptian locale.

Yes, this is WAI. 

Try 'ar-EG' locale to use Arabic digits. 

BTW, CLDR 34 (shipped with ICU 63) standardized on European digits for the default Arabic locale (e.g. 'ar') with regional variants (e.g. ar-EG) to have Arabic digits. 

So, once Firefox updates its copy of ICU, it'll have the same behavior as Chrome/v8.