Re: Regression failures after changing PostgreSQL blocksize

Hi Álvaro,

I think we can make it work

I just noticed that pg_regress provisioned `get_alternative_expectfile` for
that, and I see examples like `char{,_1,_2}.out`, but that is horrible for
maintenance (I personally think that we could have the input and expected
output in one single file).

I added a patch that would support selective matching. Check the README.md,
it contains some human readable instructions that I also used to test the
implementation. `make self-test` extracts examples from README.md and
runs pg_regress on them, i.e. test the implementation on the documentation.

https://asciinema.org/a/lFzGnv73mmOqyLWw

By default it ignores comments and spaces, and in the expected file you can
enable/disable other things, e.g. ignoring numbers in specific lines would
probably help with the 32kB failures.

Regards,
Alexandre

On Fri, Feb 20, 2026 at 9:42 PM Álvaro Herrera <alvherre(at)kurilemu(dot)de> wrote:

> On 2026-Feb-20, Alexandre Felipe wrote:
>
> > What about pattern matching? being able to write regular expressions on
> the
> > expected outputs?
>
> I doubt that will work.
>
> --
> Álvaro Herrera 48°01'N 7°57'E —
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