Re: [PATCH 15/29] ref_transaction_create(): disallow recursive pruning

Junio C Hamano [off-list ref] writes:

If a casual reader sees this code:

    ref_transaction_delete(transaction, r->name, r->sha1,
			   REF_ISPRUNING | REF_NODEREF, NULL, &err)

it gives an incorrect impression that there may also be a valid case
to make a "delete" call with ISPRUNING alone without NODEREF, in
other codepaths and under certain conditions, and write an incorrect

    ref_transaction_delete(transaction, refname, sha1,
			   REF_ISPRUNING, NULL, &err)

in her new code.  Or a careless programmer and reviewer may not even
memorize and remember what the new world order is when they see such
a code and let it pass.

As I understand that we declare that "to prune a ref from set of
loose refs is to prune the named one, never following a symbolic
ref" is the new world order with this patch, making sure that
ISPRUNING automatically and always mean NODEREF will eliminate the
possibility that any new code makes an incorrect call to "delete",
which I think is much better.

... but my understanding of the point of this patch may be flawed,
in which case I of course am willing to be enlightened ;-)