Re: Bug/request: the empty string should be a valid git note
Apologies for re-sending; unclear whether my email was delivered since I sent it before my subscription was confirmed.
On 20 Sep 2014, at 20:47, James H. Fisher <jhf@trifork.com> wrote:
Show 38 quoted lines
> In the documentation for git notes [1] I read:
>
> In principle, a note is a regular Git blob, and any kind of (non-)format is accepted.
>
> Then, since the empty string is a valid regular Git blob, the empty string is also a valid git note.
>
> Therefore this behavior was unexpected for me:
>
>> git notes --ref=foo add -m ''
> Removing note for object 97b8860c071898d9e162678ea1035a8ced2f8b1f
>
> I was surprised to see that this behavior was deliberately introduced:
>
>> git log -1 a0b4dfa
> commit a0b4dfa9b35a2ebac578ea5547b041bb78557238
> Author: Johan Herland <johan@herland.net>
> Date: Sat Feb 13 22:28:24 2010 +0100
>
> Teach builtin-notes to remove empty notes
>
> When the result of editing a note is an empty string, the associated note
> entry should be deleted from the notes tree.
>
> This allows deleting notes by invoking either "git notes -m ''" or
> "git notes -F /dev/null".
>
> Signed-off-by: Johan Herland <johan@herland.net>
> Signed-off-by: Junio C Hamano <gitster@pobox.com>
>
> I don’t understand what the motivation for this change was. Yes, it "allows deleting notes" by providing the empty string, but there is a specific subcommand for removal of a note, `git notes remove`, which makes this intention much clearer.
>
> I have specific motivation for wanting to store the empty string as a git note, as distinct from the non-existence of a note for the object. (Specifically I have a tool to annotate a commit with a list of files that satisfy a certain condition. The empty string represents the empty list, a valid value which asserts that no files satisfied the condition. I can imagine many other use cases for which the empty string is a useful git note.)
>
> Does anyone know why we have the existing behavior? Is it for "technical reasons” or was it actually considered desirable?
>
> James Fisher
>
> [1]: https://www.kernel.org/pub/software/scm/git/docs/git-notes.html