Re: Recent unresolved issues: shallow clone

Junio C Hamano [off-list ref] writes:

Maybe after the update to G happens (which means you now have C,
F, G but not A B D E commits), the client side could enumerate
commits on "rev-list ^C G" and cauterize the ones with missing
parents (in this case, F does not have one of its parents).
While doing this would help keeping the resulting commit
ancestry sane, it does not solve the problem of missing blobs
and trees.  See below.

Actually, it is more involved than the above.

The sender would give you A B D E as well, so we would not be
able to cauterise at F; instead you would do so at A, making
your shallow clone a bit deeper.  When you look at the objects
the parent gave you by running "rev-list ^C G", you would notice
that you do not have any of real parents of A, and add a new
graft.  While you are at it, you would hopefully notice that the
real parent of commit C is something you now have -- so you
remove the graft entry for C.

However, depending on what you care about more, having the
sender not to send the side branch and cauterising the result at
F _might_ be a better thing to do.  This is probably quite
involved and I offhand would not know how to efficiently
compute.