Re: [PATCH v2 1/4] t4059: test 'diff --cc' with a change from only few parents

On Sat, Apr 11, 2015 at 2:07 PM, Junio C Hamano [off-list ref] wrote:

Especially, we need to pay close attention to the discussion that
germinated the current behaviour:

  http://thread.gmane.org/gmane.comp.version-control.git/15486/focus=15519

I recall that the "diff --cc" before that change was not discarding
uninteresting merges sufficiently and the two commits were a
deliberate attempt to reject what your series wants to show as
uninteresting hunks.

Two suggestions.

 - This is primarily for 2/4, but can we make it more clear in the

Eh, sorry, I obviously meant 3/4. And let me half-retract this suggestion
and put it on hold; the code-flow has become sufficiently different that
special-casing two-way merge may not be worth it after all.

   code that we do this "include more" change only on Octopus
   merges?  This change should not make any difference for two-way
   merges and I'd prefer to avoid extra processing of finding
   matching hunks and combining, only to discard the result.

 - Can you run "diff --cc" with and without your patches to the
   "merge from hell" commit mentioned in the original thread and see
   if we show more hunks with your patches, and make sure what are
   shown additionally looked really "interesting"?

This one still stands. We'd be interested to see what difference this
makes in the real world project history.

Thanks.