iOS 15 compatibility fixes

Sources/ASCollectionView/Datasource/ASDiffableDataSourceCollectionView.swift

@@ -10,20 +10,20 @@ class ASDiffableDataSourceCollectionView<SectionID: Hashable>: ASDiffableDataSou
 	/// The type of closure providing the cell.
 	public typealias Snapshot = ASDiffableDataSourceSnapshot<SectionID>
 	public typealias CellProvider = (UICollectionView, IndexPath, ASCollectionViewItemUniqueID) -> ASCollectionViewCell?
-	public typealias SupplementaryProvider = (UICollectionView, String, IndexPath) -> ASCollectionViewSupplementaryView?
+	public typealias SupplementaryProvider = (UICollectionView, String, IndexPath) -> ASCollectionViewSupplementaryView
 
 	private weak var collectionView: UICollectionView?
 	var cellProvider: CellProvider
-	var supplementaryViewProvider: SupplementaryProvider?
+	var supplementaryViewProvider: SupplementaryProvider
 
-	public init(collectionView: UICollectionView, cellProvider: @escaping CellProvider)
+	public init(collectionView: UICollectionView, cellProvider: @escaping CellProvider, supplementaryViewProvider: @escaping SupplementaryProvider)
 	{
 		self.collectionView = collectionView
 		self.cellProvider = cellProvider
+		self.supplementaryViewProvider = supplementaryViewProvider
 		super.init()
 
 		collectionView.dataSource = self
-		collectionView.register(ASCollectionViewSupplementaryView.self, forSupplementaryViewOfKind: supplementaryEmptyKind, withReuseIdentifier: supplementaryEmptyReuseID)
 	}
 
 	private var firstLoad: Bool = true
@@ -73,18 +73,8 @@ class ASDiffableDataSourceCollectionView<SectionID: Hashable>: ASDiffableDataSou
 		return cell
 	}
 
-	private let supplementaryEmptyKind = UUID().uuidString // Used to prevent crash if supplementaries defined in layout but not provided by the section
-	private let supplementaryEmptyReuseID = UUID().uuidString
-
 	func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView
 	{
-		guard let cell = supplementaryViewProvider?(collectionView, kind, indexPath)
-		else
-		{
-			let empty = collectionView.dequeueReusableSupplementaryView(ofKind: supplementaryEmptyKind, withReuseIdentifier: supplementaryEmptyReuseID, for: indexPath)
-			(empty as? ASCollectionViewSupplementaryView)?.setAsEmpty(supplementaryID: ASSupplementaryCellID(sectionIDHash: 0, supplementaryKind: supplementaryEmptyKind))
-			return empty
-		}
-		return cell
+		return supplementaryViewProvider(collectionView, kind, indexPath)
 	}
 }

Sources/ASCollectionView/FunctionBuilders/SectionArrayBuilder.swift

@@ -44,7 +44,7 @@ public func buildSectionArray<SectionID: Hashable>(@SectionArrayBuilder <Section
 }
 
 @available(iOS 13.0, *)
-@_functionBuilder
+@resultBuilder
 public struct SectionArrayBuilder<SectionID> where SectionID: Hashable
 {
 	public typealias Section = ASCollectionViewSection<SectionID>

Sources/ASCollectionView/FunctionBuilders/ViewArrayBuilder.swift

@@ -4,7 +4,7 @@ import Foundation
 import SwiftUI
 
 @available(iOS 13.0, *)
-@_functionBuilder
+@resultBuilder
 public struct ViewArrayBuilder
 {
 	public enum Wrapper

Sources/ASCollectionView/Implementation/ASCollectionView.swift

@@ -218,7 +218,7 @@ public struct ASCollectionView<SectionID: Hashable>: UIViewControllerRepresentab
 
 			cv.register(Cell.self, forCellWithReuseIdentifier: cellReuseID)
 
-			dataSource = .init(collectionView: cv)
+			dataSource = .init(collectionView: cv, cellProvider:
 			{ [weak self] collectionView, indexPath, itemID in
 				guard let self = self else { return nil }
 
@@ -253,32 +253,30 @@ public struct ASCollectionView<SectionID: Hashable>: UIViewControllerRepresentab
 				}
 
 				return cell
-			}
-			dataSource?.supplementaryViewProvider = { [weak self] cv, kind, indexPath in
-				guard let self = self else { return nil }
-
-				guard self.supplementaryKinds().contains(kind)
-				else
-				{
-					return nil
+			}, supplementaryViewProvider: { [weak self] cv, kind, indexPath in
+				guard let self = self else { fatalError("This shouldn't happen") }
+				if !self.supplementaryKinds().contains(kind) && !self.haveRegisteredForSupplementaryOfKind.contains(kind) {
+					cv.register(ASCollectionViewSupplementaryView.self, forSupplementaryViewOfKind: kind, withReuseIdentifier: self.supplementaryReuseID)
+					self.haveRegisteredForSupplementaryOfKind.insert(kind)
+					print("ASCOLLECTIONVIEW WARNING: Your collection View layout requested supplementary of type: \(kind) and you have not provided any content, assuming empty view")
 				}
-				guard let reusableView = cv.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: self.supplementaryReuseID, for: indexPath) as? ASCollectionViewSupplementaryView
-				else { return nil }
-
-				guard let section = self.parent.sections[safe: indexPath.section] else { reusableView.setAsEmpty(supplementaryID: nil); return reusableView }
-				let supplementaryID = ASSupplementaryCellID(sectionIDHash: section.id.hashValue, supplementaryKind: kind)
-				reusableView.supplementaryID = supplementaryID
-
+				let reusableView = cv.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: self.supplementaryReuseID, for: indexPath) as! ASCollectionViewSupplementaryView //Force cast appropriate here
+
+				guard let section = self.parent.sections[safe: indexPath.section] else { reusableView.setAsEmpty(supplementaryID: nil)
+					return reusableView
+				}
+
 				// Self Sizing Settings
 				let selfSizingContext = ASSelfSizingContext(cellType: .supplementary(kind), indexPath: indexPath)
 				reusableView.selfSizingConfig =
 					section.dataSource.getSelfSizingSettings(context: selfSizingContext)
 						?? ASSelfSizingConfig()
 
+				let supplementaryID = ASSupplementaryCellID(sectionIDHash: section.id.hashValue, supplementaryKind: kind)
 				reusableView.setContent(supplementaryID: supplementaryID, content: section.dataSource.content(supplementaryID: supplementaryID))
 
 				return reusableView
-			}
+			})
 			setupPrefetching()
 		}
 

Sources/ASCollectionView/UIKit/AS_UICollectionView.swift

@@ -49,9 +49,6 @@ public class AS_CollectionViewController: UIViewController
 		// Get current central cell
 		self.coordinator?.prepareForOrientationChange()
 
-		super.viewWillTransition(to: size, with: coordinator)
-		// The following is a workaround to fix the interface rotation animation under SwiftUI
-		view.frame = CGRect(origin: view.frame.origin, size: size)
 
 		coordinator.animate(alongsideTransition: { _ in
 			self.view.setNeedsLayout()
@@ -67,6 +64,8 @@ public class AS_CollectionViewController: UIViewController
 			// Completion
 			self.coordinator?.completedOrientationChange()
 		}
+
+		super.viewWillTransition(to: size, with: coordinator)
 	}
 
 	override public func viewSafeAreaInsetsDidChange()