Why does my app crash when I use an “if let” statement to unwrap an optional collectionViewCell?

Question

I am getting this error in xcode after months of this code working fine, and I can't for the life of me figure out why the code is throwing the error.

Error: Thread 1: Fatal Error: Unexpectedly found nil while unwrapping an Optional value

if let recentsRow = collectionView(collectionView, cellForItemAt: recentsIndex) as? DashboardRowCollectionViewCell {
        recentsRow.documents = recents ?? []
}

if let favoritesRow = collectionView(collectionView, cellForItemAt: favoritesIndex) as? DashboardRowCollectionViewCell {
        favoritesRow.documents = favorites ?? []
}

Sorry if this has already been asked, but I looked around the site for a while and still was unable to come up with a solution.

Edit: I do not have this issue when running the app in a simulator. I also didn't have this issue before I updated XCode.

Edit 2: The debugger has told me that collectionView is nil, but I am still unsure as to why it is nil.

Here is how collectionView is defined in my ViewController: @IBOutlet weak var collectionView: UICollectionView!

Answer 1

While I am not sure why the collectionview was nil in the first place, I fixed my application from crashing by surrounding the offending code with the following:

if collectionView != nil {
    ... code goes here ...
}

This will be the accepted answer until someone comes along to explain why it was nil to begin with.

Edit: If you are trying to figure out why it was nil and want the ViewController code that the problem belongs to, I'll be happy to provide it.