From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: [OSSTEST PATCH] build_clone: git clean newly cloned trees Date: Thu, 29 Oct 2015 16:01:04 +0000 Message-ID: <563242C0.4040701@citrix.com> References: <1446134260-13253-1-git-send-email-ian.jackson@eu.citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1ZrpdW-0003UK-8v for xen-devel@lists.xenproject.org; Thu, 29 Oct 2015 16:01:10 +0000 In-Reply-To: <1446134260-13253-1-git-send-email-ian.jackson@eu.citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Jackson , xen-devel@lists.xenproject.org Cc: Ian Campbell List-Id: xen-devel@lists.xenproject.org On 29/10/15 15:57, Ian Jackson wrote: > This may seem redundant, however: > > git does not track empty directories. So it can happen that a > directory is created as part of `git clone', but is empty in the > revision switched to with `git checkout'. > > In this situation, the tree we are going to build ought not to contain > this directory, because that directory will not (in general) be > produced, eg when the revision being switched to becomes master. > > We can use git clean to produce a working tree whose contents - > including the presence or absence of empty directories - depends only > on the commit we are trying to check out, and not on the previous > states of the git history or working tree. > > For example, if a directory is made empty (ie, deleted, since git does > not distinguish) in xen.git#staging, osstest's clones of > xen.git#master will produce the directory, but `git checkout' of > staging won't delete it. If the xen.git build system mistakenly > depends on this directory, we won't detect this until the deletion > reaches master. This situation actually occurred with xen.git#598e97f > "tools/python: remove broken xl binding" (fixed in b261366f). > > Signed-off-by: Ian Jackson > CC: Andrew Cooper Reviewed-by: Andrew Cooper > --- > Osstest/TestSupport.pm | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/Osstest/TestSupport.pm b/Osstest/TestSupport.pm > index f9eba6b..aa41952 100644 > --- a/Osstest/TestSupport.pm > +++ b/Osstest/TestSupport.pm > @@ -1231,6 +1231,7 @@ END > END > (length($r{"revision_$which"}) ? < git checkout '$r{"revision_$which"}' > + git clean -xdf > END > } else { > die "$vcs $which $tree ?";