Re: [PATCH] branch: delete now accepts '-' as branch name

From: Junio C Hamano <gitster@pobox.com>
Date: Feb 16, 2022, 19:41 UTC
Message-ID: <xmqqv8xed2f3.fsf@gitster.g>
In-Reply-To: <00720bfb-c7b7-aaf2-e846-19b08d7b9cf4@sunshineco.com>

Eric Sunshine <sunshine@sunshineco.com> writes:

Show 18 quoted lines

> On 2/16/22 11:54 AM, Junio C Hamano wrote:
>> From: "Erlend E. Aasland" <erlend.aasland@innova.no>
>>> This makes it easy to get rid of short-lived branches:
>>>
>>> $ git switch -c experiment
>>> $ git switch -
>>> $ git branch -D -
>> Or you can use @{-1} directly.  Or short-lived experiment can
>> directly be done on HEAD without any branch ;-)
>> Thanks for trying to make Git better.
>
> Patches implementing this behavior for `git branch -D` have been
> submitted previously but were rejected (if I recall correctly) since 
> "delete" is a destructive operation, unlike other cases in which `-`
> is accepted. A relatively recent submission and ensuing discussion is
> at [1].
>
> [1]: https://lore.kernel.org/git/20200501222227.GE41612@syl.local/T/

I think the thread around <vpqh944eof7.fsf@anie.imag.fr> is what you have in mind as the origin of

 * "-" usually stands for "read from standard input" and using it to
   mean "the previous branch" is a source of confusion, and cannot
   be defended with the excuse of "'cd -' is used to go back to
   where we were" when the command is not going back to that branch
   (i.e. not "checkout -" or "switch -").

 * it is doubly dubious to make it easy to type "-" to cause
   something destructive.

 * on the other hand, since "checkout -" already makes "-" as a
   synonym to "@{-1}", not supporting it elsewhere may appear
   inconsistent.

I personally am sympathetic to the first point, but not that sympathetic to the second one. We made it worse since then by accepting "merge -", which is not about going back, though.