Swift 5.7 - Issues with Task Cancellation and Memory Leaks in Async/Await
Can someone help me understand I've been banging my head against this for hours. I'm working on a personal project and I'm experiencing unexpected behavior when trying to cancel a task in Swift 5.7 using async/await. I have a function that fetches data from a remote API and I want to give users the option to cancel the request if it takes too long. I have implemented a cancellation mechanism using `Task` but I'm noticing that even after cancellation, the memory for the task is not being released, leading to memory leaks. Here's my implementation: ```swift import Foundation class DataFetcher { private var task: Task<Void, Never>? = nil func fetchData(completion: @escaping (Data?) -> Void) { task = Task { do { let url = URL(string: "https://api.example.com/data")! let (data, response) = try await URLSession.shared.data(from: url) if let httpResponse = response as? HTTPURLResponse, httpResponse.statusCode == 200 { completion(data) } else { completion(nil) } } catch { print("Error fetching data: \(error)") completion(nil) } } } func cancelFetch() { task?.cancel() task = nil // Trying to release the task reference } } ``` When I call `fetchData` and then immediately call `cancelFetch`, I would expect that the memory should be released, but instruments show that the task is still retained in memory. Additionally, I see warnings about potential memory leaks related to the completion handler being retained. I've tried capturing the self reference as weak in the completion handler, but that doesn’t seem to help. ```swift completion: { [weak self] data in guard let self = self else { return } // Process data } ``` Am I missing something in my cancellation logic or is there an underlying issue with how Swift handles task cancellation in async/await? Any advice on proper cancellation and ensuring memory is freed up would be greatly appreciated! I'd really appreciate any guidance on this. I'd really appreciate any guidance on this.