Re: Can we clarify the purpose of `git diff -s`?

[ I apologize for not being more reactive the last few years. I still 
love Git and this ml, but I'm struggling to find time to contribute. ]

On 5/11/23 19:37, Junio C Hamano wrote:

The behaviour came in the v1.8.4 days with a series that was merged
by e2ecd252 (Merge branch 'mm/diff-no-patch-synonym-to-s',
2013-07-22), which

  * made "--no-patch" a synonym for "-s";

  * fixed "-s --patch", in which the effect of "-s" got stuck and did
    not allow the patch output to be re-enabled again with "--patch";

  * updated documentation to explain "--no-patch" as a synonym for
    "-s".

While it is very clear that the intent of the author was to make it
a synonym for "-s" and not a "feature-wise enable/disable" option,
that is what we've run with for the past 10 years.

That's too old for me to remember exactly my state of mind, but if you 
want to do a bit of archeology, the origin is there:

https://public-inbox.org/git/51E3DC47.70107@googlemail.com/

Essentially, Stefan Beller was using 'git show --format="%ad"' and 
expecting it to show only the author date, and for merge commits it also 
showed the patch (--cc). I suggested -s and noticed that the option 
wasn't easily discoverable, hence the patch series to better document it 
and add --no-patch as a synonym.

Probably I did not get all the subtleties of the different kinds of 
outputs. I guess I considered the output of diff to be the one specified 
by --format plus the patch (not considering --raw, --stat & friends), 
hence "get only the output specified by --format" and "disable the 
patch" were synonym to me. Looking more closely, it's rather clear to me 
they are not, and that

   git show --raw --patch --no-patch

should be equivalent to

   git show --raw

Cheers,

-- 
Matthieu Moy
https://matthieu-moy.fr/