Re: Order changes in PG16 since ICU introduction

On Fri, 2023-04-21 at 11:27 -0400, Regina Obe wrote:
> A couple of days ago, our PostGIS PG16 bots started failing with
> order
> changes in text.
> We have our tests set to locale=c

Are you sure it's still using the C locale? The results seem to be
explainable if the locale switched from "C" to "en-US-x-icu":

The results of the following are the same in v15 and v16:

select 'RM(25)/nodes|+|21|1' collate "C" < 'RM(25)/nodes|-|21|' collate
"C"; -- true

select 'RM(25)/nodes|+|21|1' collate "en-US-x-icu" < 'RM(25)/nodes|-
|21|' collate "en-US-x-icu"; -- false

I suspect when the initdb and configure defaults changed from libc to
ICU, then your locale changed.

Regards,
    Jeff Davis