[PATCH] Support % wildcard in extension upgrade filenames

At PostGIS we've been thinking of ways to have better support, from
PostgreSQL proper, to our upgrade strategy, which has always consisted
in a SINGLE upgrade file good for upgrading from any older version.

The current lack of such support for EXTENSIONs forced us to install
a lot of files on disk and we'd like to stop doing that at some point
in the future.

The proposal is to support wildcards for versions encoded in the
filename so that (for our case) a single wildcard could match "any
version". I've been thinking about the '%' character for that, to
resemble the wildcard used for LIKE.

Here's the proposal:
https://lists.osgeo.org/pipermail/postgis-devel/2022-February/029500.html

A very very short (and untested) patch which might (or
might not) support our case is attached.

The only problem with my proposal/patch would be the presence, on the
wild, of PostgreSQL EXTENSION actually using the '%' character in
their version strings, which is currently considered legit by
PostgreSQL.

How do you feel about the proposal (which is wider than the patch) ?

--strk;

Libre GIS consultant/developer
https://strk.kbt.io/services.html