Does Task cancellation propagate to URLSessionTasks?

Using Swift
,
2

Yes. Consider this test code:

import Foundation

func main() async {
    let t = Task {
        do {
            print("\(Date.now): task will start")
            let url = URL(string: "https://postman-echo.com/delay/10")!
            let request = URLRequest(url: url, cachePolicy: .reloadIgnoringLocalCacheData, timeoutInterval: 60.0)
            let (data, response) = try await URLSession.shared.data(for: request)
            print("\(Date.now): task did complete, response: \(response), data: \(data)")
        } catch {
            print("\(Date.now): task did error")
        }
    }
    if true {
        try? await Task.sleep(for: .seconds(1))
        print("\(Date.now): will cancel task")
        t.cancel()
        print("\(Date.now): did cancel task")
    }
    print("\(Date.now): waiting")
    try? await Task.sleep(for: .seconds(60))
}

await main()

It prints:

2023-05-18 08:18:52 +0000: task will start
2023-05-18 08:18:53 +0000: will cancel task
2023-05-18 08:18:53 +0000: did cancel task
2023-05-18 08:18:53 +0000: waiting
2023-05-18 08:18:53 +0000: task did error

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Quinn “The Eskimo!” @ DTS @ Apple

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