NSOperationQueue.operationCount always return 0

correction to dequeue method

Author: mbvreddy

Foundation/NSOperation.swift

@@ -204,6 +204,7 @@ internal struct _OperationList {
     var all = [NSOperation]()
 
     mutating func insert(_ operation: NSOperation) {
+        all.append(operation)
         switch operation.queuePriority {
         case .VeryLow:
             veryLow.append(operation)
@@ -257,22 +258,24 @@ internal struct _OperationList {
     }
 
     mutating func dequeue() -> NSOperation? {
+        var result : NSOperation?
         if veryHigh.count > 0 {
-            return veryHigh.remove(at: 0)
+            result = veryHigh.remove(at: 0)
+        } else if high.count > 0 {
+            result = high.remove(at: 0)
+        } else if normal.count > 0 {
+            result = normal.remove(at: 0)
+        } else if low.count > 0 {
+            result = low.remove(at: 0)
+        } else if veryLow.count > 0 {
+            result = veryLow.remove(at: 0)
         }
-        if high.count > 0 {
-            return high.remove(at: 0)
-        }
-        if normal.count > 0 {
-            return normal.remove(at: 0)
-        }
-        if low.count > 0 {
-            return low.remove(at: 0)
-        }
-        if veryLow.count > 0 {
-            return veryLow.remove(at: 0)
+
+        if let idx = all.index(of: result!) {
+            all.remove(at: idx)
         }
-        return nil
+
+        return result
     }
 
     var count: Int {

TestFoundation/TestNSOperationQueue.swift

@@ -0,0 +1,36 @@
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See http://swift.org/LICENSE.txt for license information
+// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+
+
+
+#if DEPLOYMENT_RUNTIME_OBJC || os(Linux)
+import Foundation
+import XCTest
+#else
+import SwiftFoundation
+import SwiftXCTest
+#endif
+
+class TestNSOperationQueue : XCTestCase {
+    static var allTests: [(String, TestNSOperationQueue -> () throws -> Void)] {
+        return [
+            ("test_OperationCount", test_OperationCount)
+        ]
+    }
+    
+    func test_OperationCount() {
+        let queue = NSOperationQueue()
+        let op1 = NSBlockOperation(block: { sleep(2) })
+        queue.addOperation(op1)
+        XCTAssertTrue(queue.operationCount == 1)
+        /* uncomment below lines once Dispatch is enabled in Foundation */
+        //queue.waitUntilAllOperationsAreFinished()
+        //XCTAssertTrue(queue.operationCount == 0)
+    }
+}

TestFoundation/main.swift

@@ -46,6 +46,7 @@ XCTMain([
     testCase(TestNSNull.allTests),
     testCase(TestNSNumber.allTests),
     testCase(TestNSNumberFormatter.allTests),
+    testCase(TestNSOperationQueue.allTests),
     testCase(TestNSOrderedSet.allTests),
     testCase(TestNSPipe.allTests),
     testCase(TestNSPredicate.allTests),