Re: [PATCH v2 1/3] diff-files --raw: handle intent-to-add files correctly

From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Jun 24, 2020, 13:34 UTC
Message-ID: <nycvar.QRO.7.76.6.2006241528290.54@tvgsbejvaqbjf.bet>
In-Reply-To: <20200624071116.GA79097@mail.clickyotomy.dev>

Hi Srinidhi,

On Wed, 24 Jun 2020, Srinidhi Kaushik wrote:

Show 6 quoted lines

> > The underlying problem is that some time ago, the (already incorrect)
> > empty blob constant was replaced by the empty tree constant, by mistake. I
> > contributed a patch series to fix that, and Cc:ed you you in v2 that I
> > sent out earlier today.
>
> Thanks for CC-ing me!

Of course!

Show 7 quoted lines

> > -  :000000 100644 0000000 $(git rev-parse --short $hash_t) A$(printf "\t")empty
> > -  :000000 100644 0000000 $(git rev-parse --short $hash_t) A$(printf "\t")not-empty
> > +  :000000 100644 0000000 $(git rev-parse --short $hash_e) A$(printf "\t")empty
> > +  :000000 100644 0000000 $(git rev-parse --short $hash_n) A$(printf "\t")not-empty
>
> Changing the test-case to reflect to the hash of the blob also makes
> sense.

Yes, that's the post-image side. The pre-image side is marked with 0000000 (which is Git's way to say "dunno! no current information in the index").

And it is reflecting the `--patch` case that is unfortunately not visible in the diff context:

        cat >expect.diff_p <<-EOF &&
        diff --git a/empty b/empty
        new file mode 100644
        index 0000000..$(git rev-parse --short $hash_e)
        diff --git a/not-empty b/not-empty
        new file mode 100644
        index 0000000..$(git rev-parse --short $hash_n)
        --- /dev/null
        +++ b/not-empty
        @@ -0,0 +1 @@
        +$content
        EOF

(This comment is not so much directed at you as it really is a continuation of my reply to Junio, see https://lore.kernel.org/git/nycvar.QRO.7.76.6.2006241517320.54@tvgsbejvaqbjf.bet/)

Show 10 quoted lines

> [...]
>
> > > +     hash_e=$(git hash-object empty) &&
> > > +     hash_n=$(git hash-object not-empty) &&
> > > +     hash_t=$(git hash-object -t tree /dev/null) &&
> >
> > > So this is the hash of the empty tree object, and...
>
> I guess we can get rid of the `hash_t' assignment here, because it
> won't be used anywhere else in the test.

Right! I _knew_ there was something I wanted to do, still, but then forgot all about it...

Thanks, Dscho