63.1 vs 63.2 and Reiwa support

[srl295]

(ICU 64.2 supports the Reiwa era, as does 63.2 and others.)

Steps to reproduce: (I was not able to do step 2 exactly, so this is somewhat of a theory. Not sure how to run npm against a self-built Node yet.)

1. configured/compiled Node with --with-intl=small-icu --with-icu-source=https://github.com/unicode-org/icu/releases/download/release-63-2/icu4c-63_2-src.tgz --download=all

2. use npm install full-icu as directed. It will download the ICU 63 package, which will be 63.1 (not 63.2).

3. The following are incorrect, and show that the 63.1 (not 63.2) data is being fetched:

$ ~/src/node/node --icu-data-dir=node_modules/icu4c-data/ -p "new Date('5/1/2019').toLocaleString('en-u-ca-japanese', {era: 'long'})"
5 1, 31 Heisei, 12:00:00 AM
$ ~/src/node/node --icu-data-dir=node_modules/icu4c-data/ -p "new Date('5/1/2019').toLocaleString('ja-u-ca-japanese', {era: 'long'})"
平成31年5月1日 0:00:00

(These should say 1 Reiwa / 令和元年5月1日 0:00:00) - note the era "令和"

[srl295]

Note, a workaround is to recompile node using --with-intl=full-icu. Don't use the full-icu package at all in that case. Node will have all data and will work properly.

[srl295]

There's no issue for ICU4C 64.2, because the full-icu data is actually 64.2 not 64.1.

[srl295]

closing as moot.