Merge pull request #1101 from bubski/operation-queue-current

Author: swift-ci

Foundation/Operation.swift

@@ -317,7 +317,13 @@ open class OperationQueue: NSObject {
     let lock = NSLock()
 #if DEPLOYMENT_ENABLE_LIBDISPATCH
     var __concurrencyGate: DispatchSemaphore?
-    var __underlyingQueue: DispatchQueue?
+    var __underlyingQueue: DispatchQueue? {
+        didSet {
+            let key = OperationQueue.OperationQueueKey
+            oldValue?.setSpecific(key: key, value: nil)
+            __underlyingQueue?.setSpecific(key: key, value: Unmanaged.passUnretained(self))
+        }
+    }
     let queueGroup = DispatchGroup()
 #endif
 

TestFoundation/TestNSOperationQueue.swift

@@ -26,6 +26,10 @@ class TestNSOperationQueue : XCTestCase {
             ("test_AsyncOperation", test_AsyncOperation),
             ("test_isExecutingWorks", test_isExecutingWorks),
             ("test_MainQueueGetter", test_MainQueueGetter),
+            ("test_CurrentQueueOnMainQueue", test_CurrentQueueOnMainQueue),
+            ("test_CurrentQueueOnBackgroundQueue", test_CurrentQueueOnBackgroundQueue),
+            ("test_CurrentQueueWithCustomUnderlyingQueue", test_CurrentQueueWithCustomUnderlyingQueue),
+            ("test_CurrentQueueWithUnderlyingQueueResetToNil", test_CurrentQueueWithUnderlyingQueueResetToNil),
         ]
     }
 
@@ -114,6 +118,51 @@ class TestNSOperationQueue : XCTestCase {
          */
         XCTAssertFalse(OperationQueue.main.isSuspended)
     }
+    
+    func test_CurrentQueueOnMainQueue() {
+        XCTAssertTrue(OperationQueue.main === OperationQueue.current)
+    }
+    
+    func test_CurrentQueueOnBackgroundQueue() {
+        let expectation = self.expectation(description: "Background execution")
+        
+        let operationQueue = OperationQueue()
+        operationQueue.addOperation {
+            XCTAssertEqual(operationQueue, OperationQueue.current)
+            expectation.fulfill()
+        }
+        
+        waitForExpectations(timeout: 1)
+    }
+    
+    func test_CurrentQueueWithCustomUnderlyingQueue() {
+        let expectation = self.expectation(description: "Background execution")
+        
+        let operationQueue = OperationQueue()
+        operationQueue.underlyingQueue = DispatchQueue(label: "underlying_queue")
+        
+        operationQueue.addOperation {
+            XCTAssertEqual(operationQueue, OperationQueue.current)
+            expectation.fulfill()
+        }
+        
+        waitForExpectations(timeout: 1)
+    }
+    
+    func test_CurrentQueueWithUnderlyingQueueResetToNil() {
+        let expectation = self.expectation(description: "Background execution")
+        
+        let operationQueue = OperationQueue()
+        operationQueue.underlyingQueue = DispatchQueue(label: "underlying_queue")
+        operationQueue.underlyingQueue = nil
+        
+        operationQueue.addOperation {
+            XCTAssertEqual(operationQueue, OperationQueue.current)
+            expectation.fulfill()
+        }
+        
+        waitForExpectations(timeout: 1)
+    }
 }
 
 class AsyncOperation: Operation {