Re: [PATCH] git-am: suggest what to do with superfluous patches

From: Junio C Hamano <gitster@pobox.com>
Date: May 31, 2010, 19:31 UTC
Message-ID: <7vwrujzx3t.fsf@alter.siamese.dyndns.org>
In-Reply-To: <20100530101926.3bac34c8jk@jk.gs@perceptron>

Jan Krüger <jk@jk.gs> writes:

Show 15 quoted lines

> Particularly in the context of rebase, conflicts frequently occur
> because the change in the patch to be applied was made obsolete by new
> upstream commits. In this case, solving the conflict effectively means
> skipping the patch. However, it's not always readily apparent that the
> patch needs to be skipped, and when people solve the conflict and try
> git rebase --continue, they get confronted with a message of
>
>   No changes - did you forget to use 'git add'?
>
> That's not very helpful if you did actually stage your changes and they
> happen to turn the patch into a no-op. This extends the message to point
> out what's going on.
>
> Signed-off-by: Jan Krüger <jk@jk.gs>
> ---

I think this is a change in a good direction; we _might_ want to allow this squelched with "advice.*" configuration, but my gut feeling is that it wouldn't probably matter much, as it is rather rare to trigger this.

Show 10 quoted lines

> diff --git a/git-am.sh b/git-am.sh
> index 87ffae2..43ea52c 100755
> --- a/git-am.sh
> +++ b/git-am.sh
> @@ -726,6 +726,8 @@ do
>  		resolved=
>  		git diff-index --quiet --cached HEAD -- && {
>  			echo "No changes - did you forget to use 'git add'?"
> +			echo "If there is nothing left to stage, chances are that something else"
> +			echo "already introduced the same changes; you might want to skip this patch."

The exact wording I'd let people to fight out, but I think this is probably better than Ramkumar's one that says "if you dropped". The user may not know that he is doing an equivalent of dropping as a side effect of the new base that had accepted the same change, and your message nudges the reader to realize that.