in Sources/_CollectionsTestSupport/MinimalTypes/_CollectionState.swift [229:240]
func reset(count: Int) {
self.count = count
switch strategy {
case .allIndices:
// Do nothing
break
case .afterChange:
self.indexValidity = Array(repeating: id, count: count)
self.endIndexValidity = id
assert(indexValidity.count == self.count)
}
}