On Sun, Oct 6, 2024 at 2:01 AM Caleb White [off-list ref] wrote:

When re-initializing a repository with a separate gitdir (the original
gitdir is moved to a new location), any linked worktrees become broken
and must be repaired to reflect the new gitdir location. For absolute
paths, this breakage is one-way, but is both ways for relative paths
(the `<worktree>/.git` and the `<repo>/worktrees/<id>/gitdir`).

Previously, `repair_worktrees` was being called which loops through all
the worktrees in the repository and updates the `<worktree>/.git` files
to point to the new gitdir. However, when both sides of the worktrees
are broken, the previous gitdir location is required to reestablish the
link.

To fix this, the function `repair_worktrees_after_gitdir_move` is
introduced. It takes the old gitdir path as an argument and repairs both
sides of the worktree.

This change fixes the following test cases in t0001-init.sh:
- re-init to move gitdir with linked worktrees
- re-init to move gitdir within linked worktree

If I understand correctly, this patch is fixing breakage resulting
from the preceding patch. Unfortunately, this approach is problematic
since it breaks bisectability of the project. In particular, it's not
sufficient for the full test suite to pass only at the end of the
patch series; rather, the entire test suite should continue to pass
after application of *each* patch in a series; we don't want one patch
to break the test suite and a subsequent patch to fix it again.

So, if my understanding is correct, please put some thought into how
to reorganize this patch series to ensure that the full test suite
passes for each patch.