In-built currency formatting not working with ICU

[Wildhoney]

Codesandbox: https://codesandbox.io/s/competent-wildflower-kpvrl5?file=/src/index.ts

When using ICU the built-in currency formatting doesn't seem to work at all — if you uncomment lines 2 and 4 you'll see that it breaks.

[adrai]

The built-in formatting is only for the i18next i18n format... but since you're using i18next-icu, this is a different i18n format and you need to check ICU instead...
i.e. "The price is: {price, number, ::currency/GBP}"

https://codesandbox.io/s/pedantic-poincare-jgnwzz

[Wildhoney]

I did check with i18next-icu and that ☝️ does work fine. I couldn't find a way in the docs to automatically add the currency symbol though for a custom formatter — in the in-built docs it seems to be a lot easier which is why I wanted to use that one.

I'm currently using the following custom formatter for price:

icu.addUserDefinedFormats({
    number: {
        PRICE_FORMAT: {
            minimumFractionDigits: 0,
            maximumFractionDigits: 2,
        },
    },
});

Is there a way to also add ::currency/GBP?

[jamuhl]

formats depend on IntlMessageFormat https://github.com/i18next/i18next-icu/blob/master/src/index.js#L66

as this basically just wraps that implementation of ICU messageformat - so you will have to look there what is possible or not