Re: WIN32 pg_import_system_collations

On Tue, Dec 14, 2021 at 5:29 AM Juan José Santamaría Flecha
<juanjo(dot)santamaria(at)gmail(dot)com> wrote:
> On Mon, Dec 13, 2021 at 9:41 AM Juan José Santamaría Flecha <juanjo(dot)santamaria(at)gmail(dot)com> wrote:
> Per path tester.

Hi Juan José,

I haven't tested yet but +1 for the feature. I guess the API didn't
exist at the time collation support was added.

+ /*
+ * Windows will use hyphens between language and territory, where ANSI
+ * uses an underscore. Simply make it ANSI looking.
+ */
+ hyphen = strchr(localebuf, '-');
+ if (hyphen)
+ *hyphen = '_';
+

This conversion makes sense, to keep the user experience the same
across platforms. Nitpick on the comment: why ANSI? I think we can
call "en_NZ" a POSIX locale identifier[1], and I think we can call
"en-NZ" a BCP 47 language tag.

+/*
+ * This test is for Windows/Visual Studio systems and assumes that a full set
+ * of locales is installed. It must be run in a database with WIN1252 encoding,
+ * because of the locales' encondings. We lose some interesting cases from the
+ * UTF-8 version, like Turkish dotted and undotted 'i' or Greek sigma.
+ */

s/encondings/encodings/

When would the full set of locales not be installed on a Windows
system, and why does this need Visual Studio? Wondering if this test
will work with some of the frankenstein/cross toolchains tool chains
(not objecting if it doesn't and could be skipped, just trying to
understand the comment).

Slightly related to this, in case you didn't see it, I'd also like to
use BCP 47 tags for the default locale for PostgreSQL 15[2].

[1] https://en.wikipedia.org/wiki/Locale_(computer_software)#POSIX_platforms
[2] https://www.postgresql.org/message-id/flat/CA%2BhUKGJ%3DXThErgAQRoqfCy1bKPxXVuF0%3D2zDbB%2BSxDs59pv7Fw%40mail.gmail.com