To prepare for using plural rules within number & duration format, this
removes the NumberFormat::Plurality enumeration.
This also adds PluralCategory::ExactlyZero & PluralCategory::ExactlyOne.
These are used in locales like French, where PluralCategory::One really
means any value from 0.00 to 1.99. PluralCategory::ExactlyOne means only
the value 1, as the name implies. These exact rules are not known by the
general plural rules, they are explicitly for number / currency format.
BCP 47 will be the single source of truth for known calendar and number
system keywords, and their aliases (e.g. "gregory" is an alias for
"gregorian"). Move the generation of available keywords to where we
parse the BCP 47 data, so that hard-coded aliases may be removed from
other generators.
As we didn't (and still don't) have Intl.PluralRules when we implemented
Intl.NumberFormat, we use a locale-unaware basic implementation to pick
a pattern based on a number's value. Templatize this method for now to
work other other format-like structures (will be used for relative-time
formatting).
Previously, we were breaking up digits into groups without regard for
the locale's minimumGroupingDigits value in the CLDR. This value is 1 in
most locales, but is 2 in locales such as pl-PL. What this means is that
in those locales, the group separator should only be inserted if the
thousands group has at least 2 digits. So 1000 is formatted as "1,000"
in en-US, but "1000" in pl-PL. And 10000 is "10,000" in en-US and
"10 000" in pl-PL.
We had a hard-coded table of number system digits copied from ECMA-402.
Turns out these digits are in the CLDR, so let's parse the digits from
there instead of hard-coding them.
There are a few algorithms in TR-35 that need to replace digits before
returning any results to callers. For example, when formatting time zone
offsets, a string like "GMT+12:34" must have its digits replaced with
the default numbering system for the desired locale.
There are 443 number system objects generated, each of which held an
array of number system symbols. Of those 443 arrays, only 39 are unique.
To uniquely store these, this change moves the generated NumericSymbol
enumeration to the public LibUnicode/NumberFormat.h header with a pre-
defined set of symbols that we need. This is to ensure the generated,
unique arrays are created in a known order with known symbols. While it
is unfortunate to no longer discover these symbols at generation time,
it does allow us to ignore unwanted symbols and perform less string-to-
enumeration conversions at lookup time.
Currently, we generate separate data files for locale and number format
related tables/methods, but provide public accessors for all of the data
in one Locale.h file. Rather than continuing this trend for date-time,
relative time, etc. formatting, it's a bit easier to reason about if the
public accessors are also in separate files.