Re: [PATCH] diff: add --ignore-blank-lines option

From: Junio C Hamano <gitster@pobox.com>
Date: Jun 17, 2013, 23:27 UTC
Message-ID: <7v38sgb9o8.fsf@alter.siamese.dyndns.org>
In-Reply-To: <CALWbr2x0gxQ8boXEa3WJUbaA8e9imt9Ri_NFmANEhJuK6Moi+A@mail.gmail.com>

Antoine Pelisse <apelisse@gmail.com> writes:

> Re-reading note: OK, This last sentence ("If not we will eventually be
> too far and break") is actually a bug. We might break before we find
> something interesting while we should keep going. For example in such
> a case, we should display like this, but won't:

Glad to see that my question has helped ;-)

Show 39 quoted lines

>> This is on the else side of if (!xch->ignore), so we are looking at
>> ignored hunk, which means there is only blank line change.  Can chg2
>> be 0 while chg1 is not zero, i.e. xch being a blank line removal?
>
> Exactly. It can be a blank line removal. But I don't want to consider
> it in the calculation.
> Here's why:
> ...
> What should be the output of diff --ignore-blank-lines ?
>
> I chose this alternative:
> @@ -1,3 +1,4 @@
> +change
>  1
>  2
>  3
> @@ -7,3 +5,4 @@
>  4
>  5
>  6
> +change
>
> While one could have chosen:
> @@ -1,10 +1,8 @@
> +change
>  1
>  2
>  3
> -
> -
> -
> -
>  4
>  5
>  6
> +change
> ...
> Nothing is interesting here, we just leave the interesting zone (if
> not already left) because everything else failed.

Yes, that asymmetry is what I was wondering if we want to have. If we show additional blanks as a significant event, I am not so sure we can say "Nothing is interesting here".

I do not feel strongly either way, but it just felt somewhat inconsistent.

Thanks.