Merge pull request swiftlang#1365 from pushkarnk/urlsession-shared

Author: swift-ci

Foundation/URLProtocol.swift

@@ -386,6 +386,8 @@ open class URLProtocol : NSObject {
     }
 
     internal class func getProtocols() -> [AnyClass]? {
+        _classesLock.lock()
+        defer { _classesLock.unlock() }
         return _registeredProtocolClasses
     }
     /*! 

Foundation/URLSession/URLSession.swift

@@ -201,8 +201,19 @@ open class URLSession : NSObject {
      * The shared session uses the currently set global URLCache,
      * HTTPCookieStorage and URLCredential.Storage objects.
      */
-    open class var shared: URLSession { NSUnimplemented() }
-    
+    open class var shared: URLSession {
+        return _shared
+    }
+
+    fileprivate static let _shared: URLSession = {
+        var configuration = URLSessionConfiguration.default
+        configuration.httpCookieStorage = HTTPCookieStorage.shared
+        //TODO: Set urlCache to URLCache.shared. Needs implementation of URLCache.
+        //TODO: Set urlCredentialStorage to `URLCredentialStorage.shared`. Needs implementation of URLCredentialStorage.
+        configuration.protocolClasses = URLProtocol.getProtocols()
+        return URLSession(configuration: configuration, delegate: nil, delegateQueue: nil)
+    }()
+
     /*
      * Customization of URLSession occurs during creation of a new session.
      * If you only need to use the convenience routines with custom

TestFoundation/TestURLSession.swift

@@ -59,11 +59,19 @@ class TestURLSession : LoopbackServerTest {
     }
 
     func test_dataTaskWithURLCompletionHandler() {
-        let urlString = "http://127.0.0.1:\(TestURLSession.serverPort)/USA"
-        let url = URL(string: urlString)!
+        //shared session
+        dataTaskWithURLCompletionHandler(with: URLSession.shared)
+
+        //new session
         let config = URLSessionConfiguration.default
         config.timeoutIntervalForRequest = 8
         let session = URLSession(configuration: config, delegate: nil, delegateQueue: nil)
+        dataTaskWithURLCompletionHandler(with: session)
+    }
+
+    func dataTaskWithURLCompletionHandler(with session: URLSession) {
+        let urlString = "http://127.0.0.1:\(TestURLSession.serverPort)/USA"
+        let url = URL(string: urlString)!
         let expect = expectation(description: "GET \(urlString): with a completion handler")
         var expectedResult = "unknown"
         let task = session.dataTask(with: url) { data, response, error in
@@ -130,10 +138,18 @@ class TestURLSession : LoopbackServerTest {
     }
 
     func test_downloadTaskWithRequestAndHandler() {
+        //shared session
+        downloadTaskWithRequestAndHandler(with: URLSession.shared)
+
+        //newly created session
         let config = URLSessionConfiguration.default
         config.timeoutIntervalForRequest = 8
-        let urlString = "http://127.0.0.1:\(TestURLSession.serverPort)/country.txt"
         let session = URLSession(configuration: config, delegate: nil, delegateQueue: nil)
+        downloadTaskWithRequestAndHandler(with: session)
+    }
+
+    func downloadTaskWithRequestAndHandler(with session: URLSession) {
+        let urlString = "http://127.0.0.1:\(TestURLSession.serverPort)/country.txt"
         let expect = expectation(description: "Download GET \(urlString): with a completion handler")
         let req = URLRequest(url: URL(string: urlString)!)
         let task = session.downloadTask(with: req) { (_, _, error) -> Void in