URLError.NetworkUnavailableReason.expensive
A reason that indicates network is unavailable because the system marked the interface as expensive.
Declaration
case expensiveDiscussion
The system determines what constitutes “expensive” based on the nature of the network interface and other factors. iOS 13 considers most cellular networks and personal hotspots expensive.
This reason occurs when the following conditions are true:
The only available network interfaces are expensive.
The URLSessionConfiguration property allowsExpensiveNetworkAccess is false.