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Date:   Fri, 4 Aug 2023 14:34:36 -0400
From:   Taylor Blau <me@ttaylorr.com>
To:     Christian Couder <christian.couder@gmail.com>
Cc:     ZheNing Hu <adlternative@gmail.com>,
        Junio C Hamano <gitster@pobox.com>,
        Git List <git@vger.kernel.org>
Subject: Re: [QUESTION] how to diff one blob with nothing
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On Fri, Aug 04, 2023 at 10:28:53AM +0200, Christian Couder wrote:
> On Fri, Aug 4, 2023 at 6:42 AM ZheNing Hu <adlternative@gmail.com> wrote:
>
> > Actually, there is no need to support a default empty blob.
> > For example, with the command "git diff --no-index <file> /dev/null",
> > it can compare a file with /dev/null, but it can only compare <file>
> > and not <oid>.
> > Therefore, using commands like "git diff <oid> /dev/null",
> > "git diff --no-index <oid> /dev/null", or even "git diff <oid> --stdin"
> > could potentially solve this issue.
>
> Maybe it would be clearer to have a new option, called for example
> "--blob-vs-file", for that then. It could support both:
>
> $ git diff --blob-vs-file <blob> <file>
>
> and:
>
> $ git diff --blob-vs-file <file> <blob>

Hmm. This feels like a case of trying to teach 'git diff' to do too
much.

Thanks,
Taylor