Re: [PATCH] rev-parse: clarify documentation for the --verify option

From: Junio C Hamano <gitster@pobox.com>
Date: Apr 2, 2013, 14:57 UTC
Message-ID: <7vobdxgeud.fsf@alter.siamese.dyndns.org>
In-Reply-To: <515A8D79.6050808@alum.mit.edu>

Michael Haggerty <mhagger@alum.mit.edu> writes:

Show 23 quoted lines

> On 04/01/2013 06:56 PM, Junio C Hamano wrote:
>> Junio C Hamano <gitster@pobox.com> writes:
>> 
>>> Because the primary use case of this option is to implement end-user
>>> input validation, I think it would be helpful to clarify use of the
>>> peeler here.  Perhaps
>>> ...
>> 
>> A "SQUASH???" patch on top of your original is queued on 'pu',
>> together with the earlier "^{object}" peeler patch.  Comments,
>> improvements, etc. would be nice.
>
> Yes, your version is better.  I would make one change, though.  In your
>
> +	Make sure the single given parameter can be turned into a
> +	raw 20-byte SHA-1 that can be used to access the object
> +	database, and emit it to the standard output. If it can't,
> +	error out.
>
> it could be made clearer that exactly one parameter should be provided.
> Maybe
>
> +	Verify that exactly one parameter is provided, and that it

That is probably better (I was hoping "the single" would mean the same to the reader, though). Thanks.

Show 6 quoted lines

> +     can be turned into a raw 20-byte SHA-1 that can be used to
> +	access the object database.  If so, emit the SHA-1 to the
> +	standard output; otherwise, error out.
>
> But this makes it sound a little like the "raw 20-byte SHA-1" will be
> output to stdout,...

I did consider that point, wrote "and outputs 40-hex" in my earlier draft, and then rejected it because it was even more misleading. The output follows the usual rules for "rev" parameters, e.g.

	git rev-parse --short --verify HEAD
	git rev-parse --symbolic --verify v1.8.2^{tree}

and "--verify" does not mean 40-hex output. That is why I left it vague as "emit it".

I agree that the wording incorrectly hints that you may be able to get 20-byte raw output. I didn't find a satisfactory phrasing.