The supplier class names ruled out by the active shipping-type and/or country filters. A supplier is excluded when a non-empty shipping filter names no scope its own scope can fulfill (per the shippingCovers hierarchy), or a non-empty country filter doesn't list its country. An empty filter constrains nothing.
The shipping-type options the given suppliers can fulfill: every scope at or below the broadest selected supplier's scope (per the shippingCovers hierarchy). Used to decide which shipping options stay selectable — an option no selected supplier can fulfill is disabled. Empty in ⇒ empty out (no supplier constraint).
The distinct home countries of the given suppliers. Used to decide which country options are still reachable: a country no selected supplier resides in can be disabled. Empty in ⇒ empty out (no supplier constraint).
One supplier's home country and coarse shipping scope.
Map of supplier class name → its SupplierShippingMeta.
Whether a supplier's shipping scope fulfills a requested one, treating scope as a hierarchy: a scope covers itself and every narrower scope (worldwide covers all, local covers only local).