Re: [PATCHv3] git apply: option to ignore whitespace differences

On Wed, Jul 29, 2009 at 9:09 AM, Junio C Hamano[off-list ref] wrote:

Giuseppe Bilotta [off-list ref] writes:

quoted

Actually, one thing that I've been thinking about doing is to adjust
the new lines to match the kind of whitespace change the context line
underwent. Example: if all the context lines had the change 4 spaces
-> tab, it would be nice to have the new lines undergo the same
change. However, this is going to be rather hard to implement.

Doing so will be actively wrong.

In the case of "whitespace=fix", it is justifiable to update ws broken
context lines while applying a ws corrected patch to a ws broken target,
and it also is justifiable not to update context lines while applying a ws
broken patch to a ws corrected target, because it is clear which one has
the correct whitespace layout (i.e. output of ws_fix_copy() by definition
is the correct outcome).  But in your example, it is not clear if the
layout using 4 spaces is correct or the one with a tab.  The tool should
refrain from guessing in such a case.

I was thinking more about consistency than 'correctness'  in this
case, actually. Typical scenario would be: patch is created for a file
using a given whitespace convention (e.g. 4 spaces). File is updated
to match the rest of the project (tabs). Patch would now introduce the
wrong whitespace convention for the new lines.

Of course, whitespace can (and should) be fixed a posteriori, but when
doing a rebase this can get quite annoying. So some kind of automatic
way to do it would be nice. But I don't think I'd get around to such a
feature any time soon. (Also, the merge case has a higher priority.)

-- 
Giuseppe "Oblomov" Bilotta