In addition to their current coverage, the index filter tests should verify that:

• When a query with a shape matching an index filter is executed, the index referenced by the filter is not used to answer the query if that index is currently hidden
• If an alternative non-hidden index is available in the filter, it is used to answer the query. Otherwise, the planner outputs a COLLSCAN.
• Un-hiding the index restores the index filter behaviour
• It is legal to set an index filter on a hidden index, but the index will not actually be used until it is made visible