On Wed, Aug 20, 2025 at 11:39 AM Derrick Stolee via GitGitGadget
[off-list ref] wrote:

From: Derrick Stolee <redacted>

Users reported an issue where objects were missing from their local
enlistments after a full repack using 'git repack -adf --path-walk'.

What is an enlistment?

This was alarming, but took a while to create a reproducer.

but => and ?

The root cause is that certain objects existed in the index and had no
second versions. These objects are usually blobs, though trees can be
included if a cache-tree exists. The issue is that the revision walk
adds these objects to the "pending" list and the path-walk API forgets
to mark the lists it creates at this point as "maybe_interesting". If
these paths only ever have a single version in the history of the repo
(including the current staged version) then the parent directory never
tries to add a new object to the list and mark the list as
"maybe_interesting". Thus, when walking the list later, the group is
skipped as it is expected that no objects are interesting. This happens
even when there are actually no UNINTERESTING objects at all! This is
based on the optimization enabled by the pack.useSparse=true config
option, which is the default.

Thus, we create a test case that demonstrates the many cases of this
issue for reproducibility:

 1. File a/b/c has only one committed version.
 2. Files a/i and x/y only exists as staged changes.

exists => exist


I didn't have any questions or spot any issues on the rest of the patch.