Re: [PATCH] fix read-tree storing wrong tree reference with modified index
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jul 9, 2010, 00:45 UTC
- Message-ID
- <7v630po53r.fsf@alter.siamese.dyndns.org>
- In-Reply-To
- <7vvd8po804.fsf@alter.siamese.dyndns.org>
Junio C Hamano <gitster@pobox.com> writes:
Show 12 quoted lines
> Heiko Voigt <hvoigt@hvoigt.net> writes: > >> * The same holds true if we are switching between two trees >> - * using read-tree -m A B. The index must match B after that. >> + * using read-tree A B (without -m). The index must match B >> + * after that. With given -m it can be a mix of the old index >> + * and the read one. > > I think the justification of the original patch is completely bogus. Why > not just drop the priming instead? Two-tree read-tree without -m does not > make much sense but the result would look like an overlay of two trees, > and is not likely to match either of the trees.
IOW, how about doing this (backported to 1.6.4 codebase) instead?
-- >8 -- Subject: [PATCH] Fix "read-tree -m A B" priming the cache-tree
In 456156d a shortcut to priming the index tree reference was introduced, but the justification for it was completely bogus.
"read-tree -m A B" is to take the index (and the working tree) that is largely based on (but does not have to match exactly) A and update it to B, while carrying the local change that does not overlap the difference between A and B, so there is no reason to expect that the resulting index should match the tree B.
Noticed and test provided by Heiko Voigt.
Signed-off-by: Junio C Hamano <gitster@pobox.com> --- builtin-read-tree.c | 5 ----- t/t1001-read-tree-m-2way.sh | 16 ++++++++++++++++ 2 files changed, 16 insertions(+), 5 deletions(-)
diff --git a/builtin-read-tree.c b/builtin-read-tree.c index 82e25ea..4fbf5f8 100644 --- a/builtin-read-tree.c +++ b/builtin-read-tree.c @@ -199,14 +199,9 @@ int cmd_read_tree(int argc, const char **argv, const char *unused_prefix) * "-m ent" or "--reset ent" form), we can obtain a fully * valid cache-tree because the index must match exactly * what came from the tree. - * - * The same holds true if we are switching between two trees - * using read-tree -m A B. The index must match B after that. */ if (nr_trees == 1 && !opts.prefix) prime_cache_tree(&active_cache_tree, trees[0]); - else if (nr_trees == 2 && opts.merge) - prime_cache_tree(&active_cache_tree, trees[1]); if (write_cache(newfd, active_cache, active_nr) || commit_locked_index(&lock_file)) diff --git a/t/t1001-read-tree-m-2way.sh b/t/t1001-read-tree-m-2way.sh index 271bc4e..6e3b601 100755 --- a/t/t1001-read-tree-m-2way.sh +++ b/t/t1001-read-tree-m-2way.sh @@ -392,4 +392,20 @@ test_expect_success \ git ls-files --stage | tee >treeMcheck.out && test_cmp treeM.out treeMcheck.out' +test_expect_success '-m references the correct modified tree' ' + echo >file-a && + echo >file-b && + git add file-a file-b && + git commit -a -m "test for correct modified tree" + git branch initial-mod && + echo b >file-b && + git commit -a -m "B" && + echo a >file-a && + git add file-a && + git ls-tree $(git write-tree) file-a >expect && + git read-tree -m HEAD initial-mod && + git ls-tree $(git write-tree) file-a >actual && + test_cmp expect actual +' + test_done
-- 1.7.2.rc2.191.gd2de1