git -C B prune
'
+test_expect_success 'prune: handle index in multiple worktrees' '
+ git worktree add second-worktree &&
+ echo "new blob for second-worktree" >second-worktree/blob &&
+ git -C second-worktree add blob &&
+ git prune --expire=now &&
+ git -C second-worktree show :blob >actual &&
+ test_cmp second-worktree/blob actual
+'
+
test_done