Featured Topics Concurrent Access Failure

FeaturedTopicsConcurrentAccessFailure.swift

  func testFeaturedTopics() {
        let count = 200
        for index in 0..<count {
            FeaturedTopics.shared[String(index)] = index
        }
        
        // The dispatch queue executes the submitted blocks in parallel and waits for all iterations to complete before returning
        DispatchQueue.concurrentPerform(iterations: count) { (index) in
            if let indexNumber = FeaturedTopics.shared[String(index)] as? Int {
                print(indexNumber)
            }
        }
        
        FeaturedTopics.shared.reset()
        
        // Re-add the values concurrently
        DispatchQueue.concurrentPerform(iterations: count) { (index) in
            print("index \(index)")
            FeaturedTopics.shared[String(index)] = index
        }
    }