Re: [BUG] git-am silently applying patches incorrectly

From: Colin Guthrie <gmane@colin.guthr.ie>
Date: Mar 7, 2011, 09:37 UTC
Message-ID: <4D74A753.2020200@colin.guthr.ie>
In-Reply-To: <7vlj0r520k.fsf@alter.siamese.dyndns.org>

'Twas brillig, and Junio C Hamano at 06/03/11 22:15 did gyre and gimble:

Show 8 quoted lines

>> > Personally I wouldn't bother making offset absolute... (equiv of
>> > abs(offset)) as knowing it applied earlier or later could be useful...
>> > the direction is lost here and I don't really see why that's nicer for
>> > the user. But maybe that's just my opinion?
> I don't have a strong opinion on this either way; I would just imitate
> what GNU patch would do, which would probably be to show the offset as-is,
> except that it flips the sign if it is being run in reverse with -R
> option.

Yeah I think that's quite sensible. I think converging with the way GNU patch does it except when there is really good reason not to makes a lot of sense, if nothing more than general familiarity and expectations.

> A bigger question I would actually care _more_ about is if this should be
> on by default without -v.  We usually do not allow fuzz by default for
> safety, and we do warn loudly when -C reduces the context and we actually
> need to use it to match the preimage.

Users used to using patch may simply think there are no offset adjustments when using git am and live in blissful ignorance. For that reason I'd say it should be on by default. But then again, I've been recently jaded by a mis-applied patch... if I'm honest, I would probably say that 99 times in a 100, I couldn't really care less (or really read) the offset adjustments.... so I can't really comment very subjectively here :s

> In any case, here is an update to match what GNU patch seems to do more
> closely.

Looks good to me!

Thanks again for looking into this issue :) Hopefully the primary fix can be pushed soon and the nice usability improvements that have spawned from it can head the same direction too :)

Col

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Colin Guthrie
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