Merge pull request swiftlang#1007 from saiHemak/nsrequesttimeout

URLRequest.timeoutInterval should override the URLSessionConfiguration.timeoutIntervalForRequest

Author: Pushkar N Kulkarni

Diff for: Foundation/NSURLSession/NSURLSessionTask.swift

@@ -634,7 +634,10 @@ fileprivate extension URLSessionTask {
 
         //set the request timeout
         //TODO: the timeout value needs to be reset on every data transfer
-        let timeoutInterval = Int(httpSession.configuration.timeoutIntervalForRequest) * 1000
+        var timeoutInterval = Int(httpSession.configuration.timeoutIntervalForRequest) * 1000
+        if request.isTimeoutIntervalSet {
+           timeoutInterval = Int(request.timeoutInterval) * 1000
+        }
         let timeoutHandler = DispatchWorkItem { [weak self] in
             guard let currentTask = self else { fatalError("Timeout on a task that doesn't exist") } //this guard must always pass
             currentTask.internalState = .transferFailed

Diff for: Foundation/URLRequest.swift

@@ -59,6 +59,11 @@ public struct URLRequest : ReferenceConvertible, Equatable, Hashable {
             _applyMutation { $0.cachePolicy = newValue }
         }
     }
+
+    //URLRequest.timeoutInterval should be given precedence over the URLSessionConfiguration.timeoutIntervalForRequest regardless of the value set,
+    // if it has been set at least once. Even though the default value is 60 ,if the user sets URLRequest.timeoutInterval
+    // to explicitly 60 then the precedence should be given to URLRequest.timeoutInterval.
+    internal var isTimeoutIntervalSet = false
 
     /// Returns the timeout interval of the receiver.
     /// - discussion: The timeout interval specifies the limit on the idle
@@ -77,6 +82,7 @@ public struct URLRequest : ReferenceConvertible, Equatable, Hashable {
         }
         set {
             _applyMutation { $0.timeoutInterval = newValue }
+            isTimeoutIntervalSet = true
         }
     }
 

Diff for: TestFoundation/TestNSURLSession.swift

@@ -21,21 +21,23 @@ class TestURLSession : XCTestCase {
 
     static var allTests: [(String, (TestURLSession) -> () throws -> Void)] {
         return [
-            ("test_dataTaskWithURL", test_dataTaskWithURL),
-            ("test_dataTaskWithURLRequest", test_dataTaskWithURLRequest),
-            ("test_dataTaskWithURLCompletionHandler", test_dataTaskWithURLCompletionHandler),
-            ("test_dataTaskWithURLRequestCompletionHandler", test_dataTaskWithURLRequestCompletionHandler),
-            ("test_downloadTaskWithURL", test_downloadTaskWithURL),
-            ("test_downloadTaskWithURLRequest", test_downloadTaskWithURLRequest),
-            ("test_downloadTaskWithRequestAndHandler", test_downloadTaskWithRequestAndHandler),
-            ("test_downloadTaskWithURLAndHandler", test_downloadTaskWithURLAndHandler),
-            ("test_finishTaskAndInvalidate", test_finishTasksAndInvalidate),
-            ("test_taskError", test_taskError),
-            ("test_taskCopy", test_taskCopy),
-            ("test_cancelTask", test_cancelTask),
-            ("test_taskTimeout", test_taskTimeout),
-            ("test_verifyRequestHeaders", test_verifyRequestHeaders),
-            ("test_verifyHttpAdditionalHeaders", test_verifyHttpAdditionalHeaders),
+//Disabling to avoid https://bugs.swift.org/browse/SR-4677 and a timeout failure
+//            ("test_dataTaskWithURL", test_dataTaskWithURL),
+//            ("test_dataTaskWithURLRequest", test_dataTaskWithURLRequest),
+//            ("test_dataTaskWithURLCompletionHandler", test_dataTaskWithURLCompletionHandler),
+//            ("test_dataTaskWithURLRequestCompletionHandler", test_dataTaskWithURLRequestCompletionHandler),
+//            ("test_downloadTaskWithURL", test_downloadTaskWithURL),
+//            ("test_downloadTaskWithURLRequest", test_downloadTaskWithURLRequest),
+//            ("test_downloadTaskWithRequestAndHandler", test_downloadTaskWithRequestAndHandler),
+//            ("test_downloadTaskWithURLAndHandler", test_downloadTaskWithURLAndHandler),
+//            ("test_finishTaskAndInvalidate", test_finishTasksAndInvalidate),
+//            ("test_taskError", test_taskError),
+//            ("test_taskCopy", test_taskCopy),
+//            ("test_cancelTask", test_cancelTask),
+//            ("test_taskTimeout", test_taskTimeout),
+//            ("test_verifyRequestHeaders", test_verifyRequestHeaders),
+//            ("test_verifyHttpAdditionalHeaders", test_verifyHttpAdditionalHeaders),
+            ("test_timeoutInterval", test_timeoutInterval),
         ]
     }
 
@@ -409,6 +411,32 @@ class TestURLSession : XCTestCase {
 
         waitForExpectations(timeout: 30)
     }
+
+    func test_timeoutInterval() {
+        let serverReady = ServerSemaphore()
+        globalDispatchQueue.async {
+            do {
+                try self.runServer(with: serverReady, startDelay: 3, sendDelay: 5, bodyChunks: 3)
+            } catch {
+                XCTAssertTrue(true)
+                return
+            }
+        }
+        serverReady.wait()
+        let config = URLSessionConfiguration.default
+        config.timeoutIntervalForRequest = 10
+        let session = URLSession(configuration: config, delegate: nil, delegateQueue: nil)
+        var expect = expectation(description: "download task with handler")
+        var req = URLRequest(url: URL(string: "http://127.0.0.1:\(serverPort)/Peru")!)
+        req.timeoutInterval = 1
+        var task = session.dataTask(with: req) { (data, _, error) -> Void in
+            defer { expect.fulfill() }
+            XCTAssertNotNil(error)
+        }
+        task.resume()
+
+        waitForExpectations(timeout: 30)
+    }
 }
 
 class SessionDelegate: NSObject, URLSessionDelegate {

Diff for: TestFoundation/main.swift

@@ -79,8 +79,7 @@ XCTMain([
     testCase(TestURLRequest.allTests),
     testCase(TestNSURLResponse.allTests),
     testCase(TestNSHTTPURLResponse.allTests),
-//Disabling to avoid https://bugs.swift.org/browse/SR-4677 and a timeout failure
-//    testCase(TestURLSession.allTests),
+    testCase(TestURLSession.allTests),
     testCase(TestNSNull.allTests),
     testCase(TestNSUUID.allTests),
     testCase(TestNSValue.allTests),