We punt from repairing the cache-tree during a branch switching if
it involves having to create a new tree object that does not yet
exist in the object store. "mkdir dir && >dir/file && git add dir"
followed by "git checkout" is one example, when a tree that records
the state of such "dir/" is not in the object store.
However, after discovering that we do not have a tree object that
records the state of "dir/", the caller failed to remember the fact
that it noticed the cache-tree entry it received for "dir/" is
invalidated, it already knows it should not be populating the level
that has "dir/" as its immediate subdirectory, and it is not an
error at all for the sublevel cache-tree entry gave it a bogus
object name it shouldn't even look at.
This led the caller to detect and report a non-existent error. The
end result was the same and we avoided stuffing a non-existent tree
to the cache-tree, but we shouldn't have issued an alarming error
message to the user.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
During the commit process, update the cache-tree. Write this updated
cache-tree so that it's ready for subsequent commands.
Add test code which demonstrates that git commit now writes the cache
tree. Make all tests test the entire cache-tree, not just the root
level.
Signed-off-by: David Turner <dturner@twitter.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add tests to confirm that invalidation of subdirectories neither over-
nor under-invalidates.
Signed-off-by: David Turner <dturner@twitter.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When git checkout checks out a branch, create or update the
cache-tree so that subsequent operations are faster.
update_main_cache_tree learned a new flag, WRITE_TREE_REPAIR. When
WRITE_TREE_REPAIR is set, portions of the cache-tree which do not
correspond to existing tree objects are invalidated (and portions which
do are marked as valid). No new tree objects are created.
Signed-off-by: David Turner <dturner@twitter.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Use 'printf %d $(whatever|wc -l)' so that the shell removes the blanks
for us.
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Acked-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the case of --mixed and --hard, we throw away the old index and
rebuild everything from the tree argument (or HEAD). So we have an
opportunity here to fill in the cache-tree data, just as read-tree
did.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In prepare_index(), we refresh the index, and then write it to disk if
this changed the index data. After running hooks we re-read the index
and compute the root tree sha1 with the cache-tree machinery.
This gives us a mostly free opportunity to write up-to-date cache-tree
data: we can compute it in prepare_index() immediately before writing
the index to disk.
If we do this, we were going to write the index anyway, and the later
cache-tree update has no further work to do. If we don't do it, we
don't do any extra work, though we still don't have have cache-tree
data after the commit.
The only case that suffers badly is when the pre-commit hook changes
many trees in the index. I'm writing this off as highly unusual.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The cache-tree optimization originally helped speed up write-tree
operation. However, many commands no longer properly maintain -- or
use an opportunity to cheaply generate -- the cache-tree data. In
particular, this affects commit, checkout and reset. The notable
examples that *do* write cache-tree data are read-tree and write-tree.
This sadly means most people no longer benefit from the optimization,
as they would not normally use the plumbing commands.
Document the current state of affairs in a test file, in preparation
for improvements in the area.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano