Fixed issue of an exception is raised when a task runs async indepentently of parallel function.

Author: dev123dev123

Ax.xcodeproj/project.xcworkspace/xcuserdata/wilsonbalderrama.xcuserdatad/UserInterfaceState.xcuserstate

@@ -44,9 +44,11 @@ final public class Ax {
   public static func parallel(tasks: [TaskClosure], result: @escaping ResultClosure) {
     let group = DispatchGroup()
     var errorFound: NSError?
+    var numTaskEntered = 0
 
     for task in tasks {
       group.enter()
+      numTaskEntered += 1
 
       DispatchQueue.global(qos: .background).async {
         task({ (error) in
@@ -55,7 +57,10 @@ final public class Ax {
             result(error)
           }
 
-          group.leave()
+          if numTaskEntered > 0 {
+            group.leave()
+            numTaskEntered -= 1
+          }
         })
       }
     }

Ax/Ax.swift

@@ -32,6 +32,21 @@ class AxTests: XCTestCase {
     }
   }
 
+  func runAsync(after seconds: Int, selfCallAfter secondsAfter: Int, closure: @escaping () -> Void) {
+    let time = DispatchTime.now() + DispatchTimeInterval.seconds(seconds)
+    let timeAfter = DispatchTime.now() + DispatchTimeInterval.seconds(secondsAfter)
+    
+    let queue = DispatchQueue(label: "com.ax.runqueue")
+    
+    queue.asyncAfter(deadline: time) { 
+      closure()
+    }
+    
+    queue.asyncAfter(deadline: timeAfter) { 
+      closure()
+    }
+  }
+  
 
 
 
@@ -267,6 +282,47 @@ class AxTests: XCTestCase {
 
 
   // Parallel tests
+  func testRunningATaskThatSometimesRunsIndependentlyOfParallelFunction() {
+    
+    let ex = expectation(description: "")
+    var numCalls = 0
+    
+    Ax.parallel(tasks: [
+  
+      { done in
+      
+        self.runAsync(after: 1, selfCallAfter: 4, closure: {
+          numCalls += 1
+          
+          if numCalls == 2 {
+            ex.fulfill()
+          }
+          
+          done(nil)
+        })
+        
+      },
+      
+      { done in
+      
+        self.runAsync(after: 1, closure: {
+          done(nil)
+        })
+        
+      }
+      
+    ]) { (error) in
+      XCTAssertNil(error)
+    }
+    
+    waitForExpectations(timeout: 8) { (error) in
+      if let error = error {
+        XCTFail("error: \(error)")
+      }
+    }
+    
+  }
+  
   func testRunningThreeTasksInParallelAndEnsureResultCallIsDoneAtFinalState() {
     let ex = expectation(description: "Testing tasks that run in parallel and are finished before result closure is called")
     var counter = 0