From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id AE49E1F66F for ; Thu, 5 Nov 2020 19:29:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732107AbgKET3C (ORCPT ); Thu, 5 Nov 2020 14:29:02 -0500 Received: from cloud.peff.net ([104.130.231.41]:49128 "EHLO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727851AbgKET3C (ORCPT ); Thu, 5 Nov 2020 14:29:02 -0500 Received: (qmail 17313 invoked by uid 109); 5 Nov 2020 19:29:02 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with ESMTP; Thu, 05 Nov 2020 19:29:02 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 25830 invoked by uid 111); 5 Nov 2020 19:29:01 -0000 Received: from coredump.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.2) by peff.net (qpsmtpd/0.94) with (TLS_AES_256_GCM_SHA384 encrypted) ESMTPS; Thu, 05 Nov 2020 14:29:01 -0500 Authentication-Results: peff.net; auth=none Date: Thu, 5 Nov 2020 14:29:01 -0500 From: Jeff King To: Patrick Steinhardt Cc: git@vger.kernel.org Subject: Re: [PATCH 1/2] update-ref: Allow creation of multiple transactions Message-ID: <20201105192901.GA121650@coredump.intra.peff.net> References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wed, Nov 04, 2020 at 03:57:17PM +0100, Patrick Steinhardt wrote: > While git-update-ref has recently grown commands which allow interactive > control of transactions in e48cf33b61 (update-ref: implement interactive > transaction handling, 2020-04-02), it is not yet possible to create > multiple transactions in a single session. To do so, one currently still > needs to invoke the executable multiple times. > > This commit addresses this shortcoming by allowing the "start" command > to create a new transaction if the current transaction has already been > either committed or aborted. Thanks for working on this. The amount of change needed is indeed quite pleasant. > diff --git a/Documentation/git-update-ref.txt b/Documentation/git-update-ref.txt > index d401234b03..48b6683071 100644 > --- a/Documentation/git-update-ref.txt > +++ b/Documentation/git-update-ref.txt > @@ -125,7 +125,8 @@ option:: > start:: > Start a transaction. In contrast to a non-transactional session, a > transaction will automatically abort if the session ends without an > - explicit commit. > + explicit commit. This command may create a new empty transaction when > + the current one has been committed or aborted already. Reading this made me wonder what would happen if we send a "start" when the current one _hasn't_ been committed or aborted. I.e., what does: git update-ref --stdin < --- a/builtin/update-ref.c > +++ b/builtin/update-ref.c > @@ -446,7 +446,18 @@ static void update_refs_stdin(void) > state = cmd->state; > break; > case UPDATE_REFS_CLOSED: > - die("transaction is closed"); > + if (cmd->state != UPDATE_REFS_STARTED) > + die("transaction is closed"); > + > + /* > + * Open a new transaction if we're currently closed and > + * get a "start". > + */ > + state = cmd->state; > + transaction = ref_transaction_begin(&err); > + if (!transaction) > + die("%s", err.buf); > + Very nice. This duplicates the state and transaction setup at the start of the function, which made me wonder if we could do this: diff --git a/builtin/update-ref.c b/builtin/update-ref.c index bb65129012..140f0d30e9 100644 --- a/builtin/update-ref.c +++ b/builtin/update-ref.c @@ -385,14 +385,10 @@ static const struct parse_cmd { static void update_refs_stdin(void) { struct strbuf input = STRBUF_INIT, err = STRBUF_INIT; - enum update_refs_state state = UPDATE_REFS_OPEN; + enum update_refs_state state = UPDATE_REFS_CLOSED; struct ref_transaction *transaction; int i, j; - transaction = ref_transaction_begin(&err); - if (!transaction) - die("%s", err.buf); - /* Read each line dispatch its command */ while (!strbuf_getwholeline(&input, stdin, line_termination)) { const struct parse_cmd *cmd = NULL; and just have it auto-open. But of course that doesn't work because we might not see an "open" command at all. Traditional callers will start with create/update/etc, and our "auto-open" would complain. > +test_expect_success 'transaction can create and delete' ' > + cat >stdin <<-EOF && > + start > + create refs/heads/create-and-delete $A > + commit > + start > + delete refs/heads/create-and-delete $A > + commit > + EOF > + git update-ref --stdin actual && > + printf "%s: ok\n" start commit start commit >expect && > + test_path_is_missing .git/refs/heads/create-and-delete > +' The tests all look quite reasonable to me. Touching .git/refs like this is a bit gross (and something we may have to deal with if we introduce reftables, etc). But it's pretty pervasive in this file, so matching the existing style is the best option for now. -Peff