text-minimessage: Add Placeholder to format Numbers and TemporalAccessors

[Joo200]

It might be a good idea to have a decent way of formatting Numbers and Dates.
Currently I have to use miniMessage.deserialize("Number is <no>", Placeholder.unparsed("no", String.valueOf(doubleValue)));

Would be nice if it could be smth like miniMessage.deserialize("Number is <no:'de-DE':'#,00'>, Formatter.formatNumber("no", doubleValue)); where #,00 is the DecimalFormat used to convert the number and de-DE is the locale tag.

Same thing for Formats for Date, Time and both combined. (miniMessage.deserialize("Date is <date:'YYYY-MM-DD'>", Placeholder.formatDate("date", myDateAsInstant)))

This PR should add those things to Placeholders. It works already fine.
However I want to add fallback values to formatDate and formatNumber. Better display a "bad" formatted message than nothing.

Possible things:

• <number:'locale':'format'>
• <number:'format'>
• <number:'locale'>
• <date:'pattern'>

Missing stuff:

• Pull Request for Docs
• Fallback Value for the DecimalFormat
• Fallback Value for the DateFormatter
• Better determination whether a string is a locale or the format for the DecimalFormat

[kezz]

Also, I don't really think this fits in Placeholder as nothing else in this class supports arguments. Although I suppose it technically it a placeholder as it just inserts one value but just optionally has formatting? Not sure, would like to hear others' thoughts.

[MiniDigger]

maybe we can have a TagResolvers class for "utils" like this?

[Joo200]

maybe we can have a TagResolvers class for "utils" like this?

I moved it to a new Formatter class. This might be not the final name, Maybe "FormatterTags" would be better?

And I added a syntax to allow formatting the decimal and grouping separator. The syntax is currently:
<name:'#,00':'AB'>, where A is the decimal separator and B is the grouping separator. The second argument is optional, the grouping separator is optional too.

Should I convert the decimal and grouping separator to single arguments? So the syntax would be instead <name:'#,00':'A':'B'>?

[Joo200]

Currently waiting for #735

[zml2008]

Can you explain why you chose to make these pre-process tags? I think they'd be better suited as inserting tags, unless the formatted date can somehow contain MiniMessage tags.

[Joo200]

The idea is this:
"<double:'en-EN':'<green>#.00;<red>-#.00'><blue> is a nice number"
This is a format which will display positive numbers in green and negative numbers in red. This is only possible with PreProcess tags.

[zml2008]

Hm, that makes sense. Do we want style to bleed through though? it might make more sense to just parse the output of the formatter as components.

[Joo200]

I'm not sure. Using PreProcess tags should be flexible here.

E.g. a gradient tag should work with the formatting in the tag. We can change it to a inserting tag instead too,

[zml2008]

Gradient tags should work with uncoloured Inserting tags as children?

I'd like to avoid pre-process tags since they have such special-cased handling within the parser at the moment, which causes problems with error message offsets mostly.

[Joo200]

Yes, you're correct. I'll change it to inserting.

[Joo200]

I rebased the PR and squashed the commits.

The class is now Formatter and I changed some stuff to be more intuitive. E.g. detecting automatically whether you provide a locale arg, a formatting arg or both.

[juanvlr]

Nice work !
It would be good to handle choice formats as well (https://docs.oracle.com/javase/7/docs/api/java/text/ChoiceFormat.html)
Exemple :
There <choice:'1#is one player':'2>are <number> players'> on the server

[kezz]

Minor nitpicks before merging!

[Joo200]

Nice work ! It would be good to handle choice formats as well (https://docs.oracle.com/javase/7/docs/api/java/text/ChoiceFormat.html) Exemple : There <choice:'1#is one player':'2>are players'> on the server

I agree, that would be nice too. I'll take a look at the weekend. Should be pretty easy

[Joo200]

Added ChoiceFormat tags in the last commit.
The syntax is <tagname:'pattern'> and can be used with Formatter.choice(String tagname, double|long number)

This will add #759 to adventure

[kezz]

Minor comments - also needs an accompanying docs PR.

[kezz]

LGTM (pending docs pr)! Thanks for getting to all the requested changes and such :) Very excited to start using these tags!