From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fhigh-b7-smtp.messagingengine.com (fhigh-b7-smtp.messagingengine.com [202.12.124.158]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E27DD1FFC7E for ; Fri, 20 Jun 2025 20:42:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.12.124.158 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750452179; cv=none; b=kABEtnIGJ5V0uGTV7ACq1VMwnPdUXypVOVNK5hjczvjDGCWLsSqJy2mX7rmtZlzbnnw1+4Ct7xP/AmnMPr1kvFeq3FwcnqYNcbcp9WzjYXj74EHHazDLJIz2/ABgQigBaWKIA+NVRVE5/ZLTIFa5PmQ5RMoXAwaGebTUQUYtddg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750452179; c=relaxed/simple; bh=aUwxr/N6hF0WFxRRLbHYX31YnI/3FIi6mGxP6Aw2r6s=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=EAj31W2Njl5OZZqwyzH4kmZU+KGBjm5LO2j6/whH9I2HerIbKEwaW9oeYXpax63YG5B0X6e4hwIZgH5mmSRJFNaDhzRSLuZnY4rmythR7//v6RJmo5njfJC2K+CAZQRxkmOINvOs6ge0x6KazAp2nXakmwQozfL6itN8Wxt0KOo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=pobox.com; spf=pass smtp.mailfrom=pobox.com; dkim=pass (2048-bit key) header.d=pobox.com header.i=@pobox.com header.b=03iRmEbH; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b=DhrqzYwZ; arc=none smtp.client-ip=202.12.124.158 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=pobox.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pobox.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pobox.com header.i=@pobox.com header.b="03iRmEbH"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="DhrqzYwZ" Received: from phl-compute-06.internal (phl-compute-06.phl.internal [10.202.2.46]) by mailfhigh.stl.internal (Postfix) with ESMTP id B6F8E25400E8; Fri, 20 Jun 2025 16:42:54 -0400 (EDT) Received: from phl-frontend-02 ([10.202.2.161]) by phl-compute-06.internal (MEProxy); Fri, 20 Jun 2025 16:42:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pobox.com; h=cc :cc:content-type:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:subject :subject:to:to; s=fm3; t=1750452174; x=1750538574; bh=8RarGg6/nS j0VAnMfVQqnwRAORZCYkuQNeDlFro6+p0=; b=03iRmEbHlrg3YVfRFGKHFCNbG7 M08XO+SOTfxr3jf2Qlu8Fco5pFcWKOzsUeuNnkJAi7ShC5P1TUTHCLROdn/zihS8 1JdIHNhBi9W75bOc/e5HU/w32rv/9IbCS1bbVd1epe3GPbgsM5k6fNXM1OPm0sfv 7VPeja9eCql/cDKFRoP/+K9NjIXu1vnM/dJTuKdL+04lSgZOhqh/aC4cUjCZx+lb u/je2NmC9X0+AYSBnyskCgiNl9ePvwKDGu4g96bR7Pu1Qm/gJu3UXUazeKp6Vp9X oxZC1Kd+hVDkmMjLco6W6rzJhJYCpjIC9ZQTSKrOOMqzTPiiemUq6XM7s4ig== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:subject:subject:to :to:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm1; t= 1750452174; x=1750538574; bh=8RarGg6/nSj0VAnMfVQqnwRAORZCYkuQNeD lFro6+p0=; b=DhrqzYwZ79SzdI9Gyo1WGvC8cXXFYtA0xch8b/+csWwBJH7/YF4 OkwbyKeYWffGzp4wrI41UMHv0CzPON8GbNhOR8HD9kcpAS+hMIqneiAIR3qnR1s/ +qEbfmpKmGHFU3QZgfC7LUV9wV8KM9QLrfCxXeoLC/hPCeDUP9jw4YjA0oEmlXW3 vty/74YYnLYhjkoHnU66Xsk3KLSKyb7w5JQ8TKuDxDBBfBJdJvbkZAPQeye6JlOV li5j8423HDBWzapg/jnbMSWnkpuvg5Av1kih+QnCJaXaYIw3mysmXkJEUSPzXwSH W1Uoqy1sq4ocCxeNdK3cVBIEdfAS+c5VqKw== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtddvgdelfeelucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfurfetoffkrfgpnffqhgenuceurghi lhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurh ephffvvefujghffffkfgggtgesthdtredttdertdenucfhrhhomheplfhunhhiohcuvecu jfgrmhgrnhhouceoghhithhsthgvrhesphhosghogidrtghomheqnecuggftrfgrthhtvg hrnhepfeevteetjeehueegffelvdetieevffeufeejleeuffetiefggfeftdfhfeeigeei necuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepghhith hsthgvrhesphhosghogidrtghomhdpnhgspghrtghpthhtohepgedpmhhouggvpehsmhht phhouhhtpdhrtghpthhtohepshgrnhgurghlshestghruhhsthihthhoohhthhhprghsth gvrdhnvghtpdhrtghpthhtohepghhithesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgt phhtthhopehpshesphhkshdrihhmpdhrtghpthhtohepghhithhsthgvrhesphhosghogi drtghomh X-ME-Proxy: Feedback-ID: if26b431b:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Fri, 20 Jun 2025 16:42:54 -0400 (EDT) From: Junio C Hamano To: "brian m. carlson" Cc: git@vger.kernel.org, Patrick Steinhardt Subject: Re: [PATCH 10/10] Enable SHA-256 by default in breaking changes mode In-Reply-To: (brian m. carlson's message of "Fri, 20 Jun 2025 19:15:26 +0000") References: <20250620011943.586596-1-sandals@crustytoothpaste.net> <20250620011943.586596-11-sandals@crustytoothpaste.net> Date: Fri, 20 Jun 2025 13:42:52 -0700 Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Precedence: bulk X-Mailing-List: git@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain "brian m. carlson" writes: > On 2025-06-20 at 15:03:23, Junio C Hamano wrote: >> Another thing that I suspect nobody wrote tests for, but we must be >> absolutely certain, is that the post-3.0 Git can still interoperate >> well with historical SHA-1 repositories (I am not talking about >> "fetch from SHA-1 into SHA-256", but "the binary does not lose >> ability to work in SHA-1 repositories or fetch/push between SHA-1 >> repositories, only because the default is set to SHA-256"), even in >> old repositories people have been using for ages without the >> core.repositoryformatversion defined. > > Yes, I have definitely tested that here before sending it out. Is there a single t/tXXXX-*.sh test that is dedicated to that interoperability, or is it spread across commands (like, t????-clone-*.sh has a test that explicitly prepares an SHA-1 and an SHA-256 repositories and then tries to clone them with the current binary to make sure the result look reasonable, and t????-push-*.sh has a test to push between a pair of SHA-1 repositories, and a pair of SHA-256 repositories, with the current binary)? > When Git > 3.0 comes out, we can switch our GIT_TEST_DEFAULT_HASH test from sha256 > to sha1 to continue to verify that those work. As I learned when > writing the SHA-256 functionality and as I'm experiencing today writing > the interop code, if clones, fetches, and pushes do not work properly, > the testsuite is completely broken with at the very least fifty-some-odd > tests failing, so I feel confident that functionality will continue to > work for SHA-1 as long as we do run an appropriate test job. OK. > Also, when we initialize a SHA-1 repository with the files ref backend, > we still use repository format version 0 without any extensions, so the > cases that cover older-style configs will still be adequately tested. We > also have some tests that even test that things work properly without a > config file, which caught a bug in this series (that I fixed before > sending it out). Very nice. Thanks.