From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Lars Ingebrigtsen Newsgroups: gmane.emacs.bugs Subject: bug#13860: 24.2; dir-locals-directory-cache unreliable in one rare case Date: Wed, 14 Aug 2019 23:18:44 -0700 Message-ID: <8736i3ymrf.fsf@mouse.gnus.org> References: <87lia4d9xh.fsf@bredband.net> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="183187"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (gnu/linux) Cc: 13860@debbugs.gnu.org To: Johan Claesson Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Thu Aug 15 08:19:15 2019 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hy96O-000lTL-Vb for geb-bug-gnu-emacs@m.gmane.org; Thu, 15 Aug 2019 08:19:13 +0200 Original-Received: from localhost ([::1]:38692 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1hy96N-00029S-Ux for geb-bug-gnu-emacs@m.gmane.org; Thu, 15 Aug 2019 02:19:11 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:48651) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1hy96H-00028w-3q for bug-gnu-emacs@gnu.org; Thu, 15 Aug 2019 02:19:06 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hy96F-0000oG-UY for bug-gnu-emacs@gnu.org; Thu, 15 Aug 2019 02:19:05 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:41650) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hy96F-0000nd-R1 for bug-gnu-emacs@gnu.org; Thu, 15 Aug 2019 02:19:03 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1hy96E-0007pV-43 for bug-gnu-emacs@gnu.org; Thu, 15 Aug 2019 02:19:03 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Lars Ingebrigtsen Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Thu, 15 Aug 2019 06:19:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 13860 X-GNU-PR-Package: emacs Original-Received: via spool by 13860-submit@debbugs.gnu.org id=B13860.156584993330065 (code B ref 13860); Thu, 15 Aug 2019 06:19:02 +0000 Original-Received: (at 13860) by debbugs.gnu.org; 15 Aug 2019 06:18:53 +0000 Original-Received: from localhost ([127.0.0.1]:50468 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1hy964-0007or-Vd for submit@debbugs.gnu.org; Thu, 15 Aug 2019 02:18:53 -0400 Original-Received: from quimby.gnus.org ([80.91.231.51]:36432) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1hy963-0007og-Fg for 13860@debbugs.gnu.org; Thu, 15 Aug 2019 02:18:52 -0400 Original-Received: from 24-104-73-23-ip-static.hfc.comcastbusiness.net ([24.104.73.23] helo=sandy) by quimby.gnus.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hy95z-00008Q-0i; Thu, 15 Aug 2019 08:18:49 +0200 In-Reply-To: <87lia4d9xh.fsf@bredband.net> (Johan Claesson's message of "Sun, 03 Mar 2013 12:01:14 +0100") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.51.188.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:165056 Archived-At: Johan Claesson writes: > Maybe i have misunderstood something but i find the cache > mechanism for directory local variables unreliable in one rare > case. If first .dir-locals.el is read and a binding say foo = 1 is > inserted in the dir-locals-directory-cache. And then foo = 2 is > written in the same second. Now next time the dir locals the old > binding foo = 1 will be returned. The cache entry is considered > valid when it should not. > > Of course it is unlikely that a user is typing so fast that they > trigger this :). But it can be triggered from Lisp. I found out > when playing with a ert test case that was tampering with a dir > local. (I'm going through old bug reports that have unfortunately gotten no responses yet.) > Here is a recipe for this: > > (defvar foo nil) > (put 'foo 'safe-local-variable 'numberp) > (let ((dir (make-temp-file "cache-test" t))) > ;; Create .dir-locals.el with foo = 1. > (with-temp-buffer > (cd dir) > (add-dir-local-variable nil 'foo 1) > (save-buffer) > (kill-buffer)) > ;; Read it into dir-locals-directory-cache > ;; and save .dir-locals.el with foo = 2. > (with-temp-buffer > (cd dir) > (make-local-variable 'foo) > (hack-dir-local-variables-non-file-buffer) > (add-dir-local-variable nil 'foo 2) > (save-buffer) > (kill-buffer)) > ;; Read it back again. > ;; It should be 2 at this point but is 1 most of the times. > ;; (At the rare occasion that seconds increase > ;; between the two add-dir-local-variable it returns 1). > (with-temp-buffer > (cd dir) > (make-local-variable 'foo) > (hack-dir-local-variables-non-file-buffer) > (delete-file dir-locals-file) > (delete-directory dir) > foo)) I'm unable to reproduce this problem in Emacs 27, but perhaps this could be a problem if the file system doesn't have sub-second resolution? Are there such file systems still in use (I mean, for something where'd you store file with file-local variables)? -- (domestic pets only, the antidote for overdose, milk.) bloggy blog: http://lars.ingebrigtsen.no