Message-ID: <a2d160b7-ff67-41f1-5176-4b520a15ef4a@dunslane.net>
Date: Wed, 13 Mar 2024 00:04:49 -0400
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Subject: Re: perl: unsafe empty pattern behavior
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To: Tom Lane <tgl@sss.pgh.pa.us>, Jeff Davis <pgsql@j-davis.com>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, pgsql-hackers@postgresql.org
References: <202403121753.lw7u5b5fjsjw@alvherre.pgsql>
 <2385813054ce4e4b3e5998600da2ce95b9509dc7.camel@j-davis.com>
 <1941562.1710284344@sss.pgh.pa.us>
From: Andrew Dunstan <andrew@dunslane.net>
In-Reply-To: <1941562.1710284344@sss.pgh.pa.us>
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On 2024-03-12 Tu 18:59, Tom Lane wrote:
> Jeff Davis <pgsql@j-davis.com> writes:
>> On Tue, 2024-03-12 at 18:53 +0100, Alvaro Herrera wrote:
>>> I also tried grepping (for things
>>> like qr{}, qr[], qr||, qr!!) and didn't find anything beyond what you
>>> have ... but I only looked for the "qr" literal, not other ways to
>>> get regexes.
>> I think that's fine. qr// seems the most dangerous, because it seems to
>> behave differently in different versions of perl.
> I wonder whether perlcritic has sufficiently deep understanding of
> Perl code that it could find these hazards.  I already checked,
> and found that there's no built-in filter for this (at least not
> in the perlcritic version I have), but maybe we could write one?
> The rules seem to be plug-in modules, so you can make your own
> in principle.


Yeah, that was my thought too. I'd start with ProhibitComplexRegexes.pm 
as a template.

If nobody else does it I'll have a go, but it might take a while.


cheers


andrew

--
Andrew Dunstan
EDB: https://www.enterprisedb.com