onefetch returns error when repository uses core.splitIndex=true

[eigengrau]

When a Git repository is using split index files, onefetch (2.10.2) fails with an error.

Steps to reproduce

repo=$(mktemp -d)
git -c core.splitIndex=true init $repo
git -C $repo commit --allow-empty -m init
env -C $repo onefetch

Example output

Initialized empty Git repository in /run/user/1000/tmp.qTh7DooE0d/.git/
[master (root-commit) 87171b0] init
[onefetch error]: unsupported mandatory extension: 'link'; class=Index (10)

[spenserblack]

This looks like it's indirectly coming from our git2 dependency, via libgit2.
https://github.com/libgit2/libgit2/blob/d9863fc19eed8135f2fbcc4ee22ea950dcd6fddf/src/index.c#L2615
https://github.com/libgit2/libgit2/blob/508361401fbb5d87118045eaeae3356a729131aa/tests/index/splitindex.c#L20

Likely related: libgit2/libgit2#6132

[Byron]

This will be fixed once onefetch fully transitions to gitoxide as I will make sure that split-index support is implemented in time. Currently git2 is still required to read configuration files and obtain the worktree status, and for the latter the index is definitely needed even though it appears to load the index eagerly.

You can subscribe to the linked tracking issue for status updates.

[o2sh]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.