Currently, LibUnicode is only parsing and generating the "long" style of
currency display names. However, the CLDR contains "short" and "narrow"
forms as well that need to be handled. Parse these, and update LibJS to
actually respect the "style" option provided by the user for displaying
currencies with Intl.DisplayNames.
Note: There are some discrepencies between the engines on how style is
handled. In particular, running:
new Intl.DisplayNames('en', {type:'currency', style:'narrow'}).of('usd')
Gives:
SpiderMoney: "USD"
V8: "US Dollar"
LibJS: "$"
And running:
new Intl.DisplayNames('en', {type:'currency', style:'short'}).of('usd')
Gives:
SpiderMonkey: "$"
V8: "US Dollar"
LibJS: "$"
My best guess is V8 isn't handling style, and just returning the long
form (which is what LibJS did before this commit). And SpiderMoney can
handle some styles, but if they don't have a value for the requested
style, they fall back to the canonicalized code passed into of().
There is quite a lot to be done here so this is just a first pass at
number formatting. Decimal and percent formatting are mostly working,
but only for standard and compact notation (engineering and scientific
notation are not implemented here). Currency formatting is parsed, but
there is more work to be done to handle e.g. using symbols instead of
currency codes ("$" instead of "USD"), and putting spaces around the
currency symbol ("USD 2.00" instead of "USD2.00").
It was previously holding a StringView, which was either a view into a
LibUnicode-generated string or a string passed from the user.
Intl.NumberFormat will need this record to hold internally-created
strings, so a StringView will not suffice (the way the steps are laid
out, that view will ultimately end up dangling).
This shouldn't be too wasteful since the StringView it was holding was
converted to a String eventually anyways.
Both at the same time because many of them call construct() in call()
and I'm not keen on adding a bunch of temporary plumbing to turn
exceptions into throw completions.
Also changes the return value of construct() to Object* instead of Value
as it always needs to return an object; allowing an arbitrary Value is a
massive foot gun.
The old versions were renamed to JS_DECLARE_OLD_NATIVE_FUNCTION and
JS_DEFINE_OLD_NATIVE_FUNCTION, and will be eventually removed once all
native functions were converted to the new format.
This method represents the Intl.NumberFormat's [[RelevantExtensionKeys]]
internal slot, so it makes more sense for this to be directly in the
class itself.
To be consistent with the style in Temporal, let's move all AOs in Intl
to their object file, rather than splitting the AOs between prototype
and constructor files.
