Fix sorting bug when using BSP tree index + add autotest.

We use stable sorting to keep insertion order. This works fine as long
as we sort a complete list of siblings in one go, and this list already
has items in insertion order. But if we shuffle such a list, the only
way to get proper sort order again (with insertion order intact), is
if each item has a sibling index. We used to have this, but we don't
have it anymore (as it's not needed for NoIndex mode).

So until we separate the BSP index into a separate class and add this
index there, we add this workaround which uses the toplevelitems list
to ensure the items have the correct order.

Reviewed-by: bnilsen

0 files changed, 0 insertions, 0 deletions