Performs one pass through the run loop in the specified mode and returns the date at which the next timer is scheduled to fire.
- iOS 2.0+
- macOS 10.0+
- UIKit for Mac 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
The run loop mode to search. You may specify custom modes or use one of the modes listed in Run Loop Modes.
The date at which the next timer is scheduled to fire, or
nil if there are no input sources for this mode.
The run loop is entered with an immediate timeout, so the run loop does not block, waiting for input, if no input sources need processing.