UIScrollView - Duplicate code produces different result - xcode

Question

I have a small test project that I'm trying to import into my production project. The ViewController that is causing the problem consists of a back ground image and a Scroll View (SV).
3 images appear in the test SV, yet only 2 appear in production. There appears to be a gap where the first image should appear.
Please note. The first image is the background image for the VC. I set it, then delete it from the array that feeds the scrollview.
Here are the two ViewControllers. Please note I embedded the VC in a TabBar and NavBar controller in test because that is what I have int production.
What is most puzzling is the code is exactly the same. The image URL's are the same. But the number of UIImageViews added to the scrollView are different. Note the last print statement in the code:
func setupList() {
print(foodPairings.count)
let imageStringURL = foodPairings[0].imageURL
let encodedURL = imageStringURL.addingPercentEncoding( withAllowedCharacters: .urlQueryAllowed)
guard let imageURL: URL = URL(string: encodedURL!) else {return}
bgImage.af_setImage(withURL: imageURL)
foodPairings.removeFirst()
print(foodPairings.count)
print(foodPairings.indices)
for i in foodPairings.indices {
let imageView = UIImageView()
let imageStringURL = foodPairings[i].imageURL
let encodedURL = imageStringURL.addingPercentEncoding( withAllowedCharacters: .urlQueryAllowed)
guard let postURL: URL = URL(string: encodedURL!) else {return}
imageView.af_setImage(withURL: postURL, placeholderImage: #imageLiteral(resourceName: "Placeholder"), filter: nil, progress: nil, imageTransition: .noTransition, runImageTransitionIfCached: false, completion: nil)
imageView.tag = i
imageView.contentMode = .scaleAspectFill
imageView.isUserInteractionEnabled = true
imageView.layer.cornerRadius = 20.0
imageView.layer.masksToBounds = true
listView.addSubview(imageView)
//attach tap detector
imageView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(didTapImageView)))
}
print(listView.subviews.count)
listView.backgroundColor = UIColor.clear
positionListItems()
}
The print statements in Test result in:
4 3
0..<3 4
Production prints the following:
4 3
0..<3 5
Why is listView.subviews.count different in production?

Answer 1

I have resolved this, but it is not clear what the source of the issue was.
In Test, my Scroll View had one subview even prior to me adding the array of UIImageViews. In Production, the Scroll View had two subviews prior to me adding the images in the array.
Just prior to the loop where I add my subviews, I remove all subviews from the ScrollView:
listView.subviews.forEach({ $0.removeFromSuperview() })
for i in foodPairings.indices {
print("SubviewCount: \(listView.subviews.count)")
let imageView = UIImageView()
...
Both my Test and Production macs are running XCode 9 Swift 4. Still remains a mystery why subview count was different.