Re: [PATCH] t: avoid sed-based chain-linting in some expensive cases

From: Jeff King <peff@peff.net>
To: "Martin Ågren" <martin.agren@gmail.com>
Cc: "Git Mailing List" <git@vger.kernel.org>,
	"Eric Sunshine" <sunshine@sunshineco.com>,
	"Ævar Arnfjörð Bjarmason" <avarab@gmail.com>
Subject: Re: [PATCH] t: avoid sed-based chain-linting in some expensive cases
Date: Sat, 15 May 2021 05:19:21 -0400	[thread overview]
Message-ID: <YJ+SGfD7kPEW6ysn@coredump.intra.peff.net> (raw)
In-Reply-To: <CAN0heSrjPJG_OGyV2dt9bOfkd07He=kBUKQ-+w5JXNae+YH7qg@mail.gmail.com>

On Fri, May 14, 2021 at 10:52:35AM +0200, Martin Ågren wrote:

> > Yeah, I suspect that would work in general. But it seems like even more
> > complexity (now you have a cache of "I linted this script at time X and
> > it was good" that has to be written). It does increase the possible
> > savings though (up to perhaps 100 or so seconds of parallel CPU in my
> > case).
> 
> Yeah, I thought about the cache. I guess it would be a list of
> known-good test script hashes / blob IDs. But what I actually meant was
> to check whether the mtime was way back in the past. It's not fool-proof
> though. You could have a network-mounted disk where the date is way off,
> or you could hack up the test script, wait for several weeks and *then*
> run it. ;)

Ah, I see. You'd set some date for "this is so old you've probably run
the linting on it by now". Yeah, that is less complex to implement. It
does feel awfully magical, though.

-Peff