Re: [Census] So who uses git?

Linus Torvalds [off-list ref] writes:

Your point that we discussed a similar flag for the "don't require a full 
checkout" is a good one: we should try to make sure that it works for both 
uses. Although maybe we decided for some reason that nobody cared about 
the non-checked-out case?

We gave them a way to add --cacheinfo but did not do any more
than that, because they are independently coming up with some
hash (not necessarily be a proper git blob object name), they
did not have the huge blob data with the working tree anyway,
and the only thing they cared about was which paths changed and
they did not even want to see how the contents changed.
I.e. "diff-tree -r" was the only thing they cared about.

If we end up doing "assume unchanged", I should remember to do a
sensible thing for "diff-index" without --cached.  It should not
look at the working tree file for paths marked as such.  This
implies one optimization in "diff-index -p" and "diff-tree -p"
may need to be disabled.  They cheat and avoid expanding blob
objects when their cache entries are clean and required blobs
are in the working tree.  If "assume unchanged" path was
actually changed, such a diff would show up as a confusing
unexpected change.

Well, the user is asking for it, so that confusion is not _my_
problem, though ;-).