URLSession spy that uses both dataTask with closures and async/await

SpyURLSession.swift

//
//  SpyURLSession.swift
//  
//

import Foundation

private class DummyURLSessionDataTask: URLSessionDataTask {
    override func resume() {
    }
}

class SpyURLSession: URLSessionProtocol {
    var asyncDataResponse: Data!
    var asyncURLResponse: URLResponse!
    var dataTaskCallCount = 0
    var dataTaskArgsRequest: [URLRequest] = []
    var dataTaskArgsCompletionHandler:
        [(Data?, URLResponse?, Error?) -> Void] = []

    func dataTask(with request: URLRequest,
                  completionHandler: @escaping (Data?, URLResponse?, Error?) -> Void
    ) -> URLSessionDataTask {
        dataTaskCallCount += 1
        dataTaskArgsRequest.append(request)
        dataTaskArgsCompletionHandler.append(completionHandler)

        return DummyURLSessionDataTask()
    }

    func data(for request: URLRequest) async throws -> (Data, URLResponse) {
        dataTaskCallCount += 1
        dataTaskArgsRequest.append(request)
        if ( self.asyncDataResponse != nil && self.asyncURLResponse != nil) {
            return (self.asyncDataResponse, self.asyncURLResponse)
        }
//        return (Data([]), URLResponse())
        let response = URLResponse(url: request.url!,
                                   mimeType: "application/json" ,
                                   expectedContentLength: 555,
                                   textEncodingName: "UTF-8")
        return (Data("{}".utf8), response)
    }
}