Junio C Hamano wrote: > Dmitry Ivankov <divanorama@xxxxxxxxx> writes: >> "from $null_sha1" and "merge $empty_branch" are already allowed so >> allow "merge $null_sha1" command too. > > Would accepting such a "merge oops-do-not-do-anything" allow > exporters' job to be simpler? Good question. I was uncomfortable with the patch and couldn't pin down why and I think you've hit it. I can imagine an importer that does cat <<EOF commit refs/heads/master from $parent merge $second_parent [etc] EOF and uses parent=0000000000000000000000000000000000000000 in the degenerate case, but it is not hard to use cat <<EOF commit refs/heads/master $optional_from_line$optional_second_parent [etc] EOF so this is not a very strong justification. Mostly it felt like a step in the right direction because once you can do it for "from", someone might try it with "merge" and it's simplest to explain the syntax if we're consistent. On the other side to be weighed against that is the danger that someone might actually start using "merge" this way. They would be making their frontend break compatibility with old versions of git fast-import for no good reason. So on second thought, it does not seem like a good direction at all. [Though the cleanup I mentioned might be nice in any case. ;-)] I wonder if anyone using "from" with a branch name that resolves in the internal branch table to $null_sha1 was actually intending that. Would any importers break if we started to forbid it? Would it make sense to add that check in "next" for a release or two and see if anyone complains? Looking at the patch for 00e2b884 (Remove branch creation command from fast-import, 2006-08-24), it looks like support for "from $null_sha1" was intentional. Maybe mailing list discussions from around then have insight. Thanks for some food for thought, Jonathan -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html