Re: pgsql: Add option to use ICU as global locale provider

On Fri, Mar 18, 2022 at 03:09:59PM -0700, Andres Freund wrote:
> Hi,
> 
> On 2022-03-18 20:28:58 +0100, Peter Eisentraut wrote:
> > Why does your patch introduce a function check_icu_locale() that is only
> > called once?  Did you have further plans for that?
> 
> I like that it moves ICU code out of dbcommands.c

Yes, it seemed cleaner this way.  But more importantly code outside pg_locale.c
really shouldn't have to deal with ICU specific version code.

I'm attaching a v2, addressing Peter and Tom comments to not duplicate the old
ICU versions attribute function.  I removed the ICU locale check entirely (for
consistency across ICU version) thus removing any need for ucol.h include in
initdb.

For the problem you reported at [1] with the meson branch, I changed createdb
tests with s/en-u-kf-upper/en@colCaseFirst=upper/, as older ICU versions don't
understand the former notation.  check-world now pass for me, using either ICU
< 54 or >= 54.

> imo there should be few
> calls to ICU functions outside of pg_locale.c. There might be an argument for
> moving *more* into such a function though.

I think it would be a good improvement.  I can work on that next week if
needed.

[1] https://www.postgresql.org/message-id/20220318000140.vzri3qw3p4aebn5p@alap3.anarazel.de