Re: git checkout --orphan skips reflogging
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Sep 13, 2011, 23:04 UTC
- Message-ID
- <7vaaa8vyc8.fsf@alter.siamese.dyndns.org>
- In-Reply-To
- <CA+gfSn-tVgj=FYiVGK7kmH4gpnXF3HUbs+f=DfRey6GrpadVYg@mail.gmail.com>
Dmitry Ivankov <divanorama@gmail.com> writes:
Show 6 quoted lines
> In short, git checkout --orphan doesn't write > HEAD_sha1 -> 00000 > entry to logs/HEAD, while git-comit will write > 00000 -> new_orphan_HEAD_sha1 > entry. And then reflog backward walk will stop on 000 -> entry and > won't see earlier history.
Funny. From the point of view of the _current_ branch, it sort of makes sense to stop the traversal at that point, but I agree for HEAD reflog that records branch switching, the traversal should not stop.
I am not sure if recording 0{40} after --orphan is the right thing to do either (for that matter, I do not necessarily think running --orphan is a sane thing to do, but that is a separate issue).
> Isn't it also a bug in reflog walking that we rely on each old_sha1 > being new_sha1 of a previous entry?
I am not all that familiar with the reflog walking (which is admittedly a bolted-on hack that injects commits with fake ancestry) code, but I think it assumes the old sha1 field on the current entry matches the new sha1 field on the previous entry, and we could change it to be a bit more robust.
The attached patch _may_ (I didn't even compile test it) remove the dependency on osha1[] and make the code consistently use nsha1[], but I think stopping at the 0{40} is pretty much fundamental in the revision walking machinery the reflog walking code is piggy-backing on, and I do not think this patch would change that.
reflog-walk.c | 17 ++++++++++++----- 1 files changed, 12 insertions(+), 5 deletions(-)
diff --git a/reflog-walk.c b/reflog-walk.c index 5d81d39..261d300 100644 --- a/reflog-walk.c +++ b/reflog-walk.c @@ -211,6 +211,13 @@ int add_reflog_for_walk(struct reflog_walk_info *info, return 0; } +static struct reflog_info *peek_reflog_ent(struct commit_reflog *clog) +{ + if (clog->recno < 0) + return NULL; + return &clog->reflogs->items[clog->recno]; +} + void fake_reflog_parent(struct reflog_walk_info *info, struct commit *commit) { struct commit_info *commit_info = @@ -223,20 +230,20 @@ void fake_reflog_parent(struct reflog_walk_info *info, struct commit *commit) return; commit_reflog = commit_info->util; - if (commit_reflog->recno < 0) { + reflog = peek_reflog_ent(commit_reflog); + if (!reflog) { commit->parents = NULL; return; } - - reflog = &commit_reflog->reflogs->items[commit_reflog->recno]; info->last_commit_reflog = commit_reflog; commit_reflog->recno--; - commit_info->commit = (struct commit *)parse_object(reflog->osha1); - if (!commit_info->commit) { + reflog = peek_reflog_ent(commit_reflog); + if (!reflog) { commit->parents = NULL; return; } + commit_info->commit = (struct commit *)parse_object(reflog->nsha1); commit->parents = xcalloc(sizeof(struct commit_list), 1); commit->parents->item = commit_info->commit; }