From: Bert Wesarg <bert.wesarg@googlemail.com>
Date: Thu, 04 Jun 2009 21:29:15 GMT
Subject: Re: [TopGit PATCH] pre-commit: check .top* files in the to-be-commited tree
Message-ID: <36ca99e90906041429o32dcc093sccaa2fba21fddd10@mail.gmail.com>
In-Reply-To: <20090604052716.GA24414@pengutronix.de>

2009/6/4 Uwe Kleine-König <u.kleine-koenig@pengutronix.de>:
> Hi Bert,
Hi Uwe,

>
> On Tue, Jun 02, 2009 at 10:40:38PM +0200, Bert Wesarg wrote:
>> We currently check fo these files only in the working tree. But we should check
>> what would be commited. We use write-tree to be able to utilize ls-tree and
>> check the result.
> <nitpick> I prefer not speaking about "us" in the commit log.  Better
> use passive voice. </nitpick>  So what about:
>
> The pre-commit hook used to check that the working copy has the .top*
> files.  Instead of that assert that the tree that is about to be
> commited has these files.
Yes, thats right, Your message is nice, you can use it for the commit.

>
>> +# I suspect this can't fail, but who knows
>> +tree=$(git write-tree) ||
>> +     die "Can't write tree"
> Actually you don't need to write the tree.  You can use:
>
>        git cat-file -t :0:.topdeps
>        -> blob
>
>        git cat-file blob :0:.topdeps | grep .
Hmm, not very nice:

$ git init
Initialized empty Git repository in /home/bertw/tmp/has-file/.git/
$ touch .topdeps
$ git add .topdeps
$ git commit -m.topdeps
[master (root-commit) 8193982] .topdeps
 0 files changed, 0 insertions(+), 0 deletions(-)
 create mode 100644 .topdeps
$ git rm .topdeps
rm '.topdeps'
$ git cat-file -t :0:.topdeps
fatal: Not a valid object name :0:.topdeps
$ echo $?
128
$ git cat-file blob :0:.topdeps | grep .
fatal: Not a valid object name :0:.topdeps
$ echo $?
1

My proposal:

$ git ls-tree --long "$(git write-tree)" .topdeps
$ echo $?
0

Here I know, that all git commands don't die(), they all succeed. The
.topdeps file, I'm looking for, is not in the tree, i.e. empty output.

Bert

> Best regards
> Uwe