URLSession and Swift Concurrency: Does cancelling a Task abort the underlying dataTask?

Goal

When a Swift Task is cancelled, ensure that the associated URLSessionDataTask is terminated immediately to prevent unnecessary network usage and battery drain.

Challenge

URLSession’s data(for:) overload forwards cancellation only when explicitly used; otherwise cancelling the enclosing Task does not affect the underlying network task. Similarly, Combine’s .timeout operator emits a timeout error but does not cancel the upstream URLSessionDataTask. The documented behavior of Swift 6 structured concurrency regarding automatic propagation of cancellation to URLSession is not clearly specified, leaving developers to guess whether additional manual cancellation is required.

Questions

• Does cancelling a Swift Task that awaits URLSession.shared.data(for:) automatically cancel the underlying URLSessionDataTask when using the overload that forwards cancellation?
• What is the documented behavior of Combine’s .timeout when applied to a URLSession dataTaskPublisher with respect to the upstream network task?
• Is there a single, documented pattern that guarantees a timeout or cancellation always aborts the network request across URLSession, Combine, and Swift concurrency?