git -C wt2 update-ref refs/worktree/foo HEAD
'
-test_expect_success 'refs/worktree must not be packed' '
+# The 'packed-refs' file is stored directly in .git/. This means it is global
+# to the repository, and can only contain refs that are shared across all
+# worktrees.
+test_expect_success REFFILES 'refs/worktree must not be packed' '
git pack-refs --all &&
test_path_is_missing .git/refs/tags/wt1 &&
test_path_is_file .git/refs/worktree/foo &&