Fixed #31956 -- Fixed crash of ordering by JSONField with a custom decoder on PostgreSQL.

[felixxm]

ticket-31956

Thanks Marc Debureaux for the report.

[felixxm]

@adamchainz @pope1ni Thanks both 👍 I pushed updates.

[charettes]

Patch LGTM, glad to see this usage of select_format and ::text removed.

The CI failures are due to JSONBAgg.convert_value returning [] instead of '[]' as expected after this commit.

django/django/contrib/postgres/aggregates/general.py

Lines 49 to 51 in 4c0b472

	def convert_value(self, value, expression, connection):
	if not value:
	return []

[felixxm]

Thanks for reviews 🚀

[laymonage]

Sorry for not jumping into this earlier. For some reason, I didn't receive an email for the ticket and I discovered this just now.

Anyway, just leaving this note:

I think the primary reason why I didn't use psycopg2.extras.register_default_jsonb was that we initially thought the contrib.postgres implementation was going to be left as it is (with a deprecation message), instead of being a subclass of the new one. If that was going to be the case, then using psycopg2.extras.register_default_jsonb would break users who still use the old implementation. That's also why the ::text cast was also backported to the django-jsonfield package.

Thanks, everyone! ✌️