Code review and tests

BlueprintUILists/Sources/BlueprintItemContent.swift

@@ -147,4 +147,8 @@ public extension BlueprintItemContent
 
         return view
     }
+
+    static func createReusableSelectedBackgroundView(frame: CGRect) -> SelectedBackgroundView {
+        self.createReusableBackgroundView(frame: frame)
+    }
 }

ListableUI/Sources/HeaderFooter/HeaderFooterContent.swift

@@ -109,7 +109,7 @@ public protocol HeaderFooterContent
     /// You do not need to provide this `typealias` unless you would like
     /// to draw a selected background view.
     ///
-    associatedtype PressedBackgroundView:UIView = BackgroundView
+    associatedtype PressedBackgroundView:UIView = UIView
 
     /// Create and return a new background view used to render the content's pressed background.
     ///
@@ -171,10 +171,10 @@ public extension HeaderFooterContent where Self.BackgroundView == UIView
     }
 }
 
-public extension HeaderFooterContent where Self.PressedBackgroundView == BackgroundView
+public extension HeaderFooterContent where Self.PressedBackgroundView == UIView
 {
     static func createReusablePressedBackgroundView(frame : CGRect) -> PressedBackgroundView
     {
-        self.createReusableBackgroundView(frame: frame)
+        PressedBackgroundView(frame: frame)
     }
 }

ListableUI/Sources/Internal/HeaderFooterContentView.swift

@@ -64,6 +64,22 @@ final class HeaderFooterContentView<Content:HeaderFooterContent> : UIView
         self.content.sizeThatFits(size)
     }
 
+    override func systemLayoutSizeFitting(_ targetSize: CGSize) -> CGSize {
+        self.content.systemLayoutSizeFitting(targetSize)
+    }
+
+    override func systemLayoutSizeFitting(
+        _ targetSize: CGSize,
+        withHorizontalFittingPriority horizontalFittingPriority: UILayoutPriority,
+        verticalFittingPriority: UILayoutPriority
+    ) -> CGSize {
+        self.content.systemLayoutSizeFitting(
+            targetSize,
+            withHorizontalFittingPriority: horizontalFittingPriority,
+            verticalFittingPriority: verticalFittingPriority
+        )
+    }
+
     override func layoutSubviews() {
         super.layoutSubviews()
 

ListableUI/Sources/Internal/ItemCell.swift

@@ -11,6 +11,8 @@ import UIKit
 protocol AnyItemCell : UICollectionViewCell
 {
     func closeSwipeActions()
+
+    func wasDequeued(with liveCells : LiveCells)
 }
 
 ///
@@ -122,13 +124,25 @@ final class ItemCell<Content:ItemContent> : UICollectionViewCell, AnyItemCell
     func closeSwipeActions() {
         self.contentContainer.performAnimatedClose()
     }
+
+    private var hasBeenDequeued = false
+
+    func wasDequeued(with liveCells : LiveCells) {
+        guard hasBeenDequeued == false else {
+            return
+        }
+
+        self.hasBeenDequeued = true
+
+        liveCells.add(self)
+    }
 }
 
 
 final class LiveCells {
 
     func add(_ cell : AnyItemCell) {
-        self.cells.insert(.init(cell))
+        self.cells.append(.init(cell: cell))
 
         self.cells = self.cells.filter { $0.cell != nil }
     }
@@ -141,25 +155,9 @@ final class LiveCells {
         }
     }
 
-    private var cells : Set<LiveCell> = []
+    private(set) var cells : [LiveCell] = []
 
-    private struct LiveCell : Hashable {
-
-        private let identifier : ObjectIdentifier
-
+    struct LiveCell {
         weak var cell : AnyItemCell?
-
-        init(_ cell : AnyItemCell) {
-            self.identifier = ObjectIdentifier(cell)
-            self.cell = cell
-        }
-
-        func hash(into hasher: inout Hasher) {
-            hasher.combine(self.identifier)
-        }
-
-        static func == (lhs : LiveCell, rhs : LiveCell) -> Bool {
-            lhs.identifier == rhs.identifier
-        }
     }
 }

ListableUI/Sources/Internal/UIView+Additions.swift → ListableUI/Sources/Internal/UIView.swift

@@ -1,5 +1,5 @@
 //
-//  UIView+Additions.swift
+//  UIView.swift
 //  ListableUI
 //
 //  Created by Kyle Van Essen on 10/28/20.

ListableUI/Sources/Internal/UIViewPropertyAnimator+System.swift → ListableUI/Sources/Internal/UIViewPropertyAnimator.swift

@@ -1,5 +1,5 @@
 //
-//  UIViewPropertyAnimator+System.swift
+//  UIViewPropertyAnimator.swift
 //  ListableUI
 //
 //  Created by Kyle Bashour on 4/17/20.

ListableUI/Sources/Item/ItemContent.swift

@@ -178,7 +178,7 @@ public protocol ItemContent where Coordinator.ItemContentType == Self
     /// You do not need to provide this `typealias` unless you would like
     /// to draw a selected background view.
     ///
-    associatedtype SelectedBackgroundView:UIView = BackgroundView
+    associatedtype SelectedBackgroundView:UIView = UIView
 
 
     /// Create and return a new background view used to render the content's selected background.
@@ -295,11 +295,11 @@ public extension ItemContent where BackgroundView == UIView
 
 
 /// Provide a UIView when no special selected background view is specified.
-public extension ItemContent where BackgroundView == SelectedBackgroundView
+public extension ItemContent where BackgroundView == UIView
 {
-    static func createReusableSelectedBackgroundView(frame : CGRect) -> BackgroundView
+    static func createReusableSelectedBackgroundView(frame : CGRect) -> SelectedBackgroundView
     {
-        self.createReusableBackgroundView(frame: frame)
+        SelectedBackgroundView(frame: frame)
     }
 }
 

ListableUI/Sources/ListView/ListView.DataSource.swift

@@ -41,7 +41,7 @@ internal extension ListView
                 environment: environment
             )
 
-            self.liveCells.add(cell)
+            cell.wasDequeued(with: self.liveCells)
 
             return cell
         }

ListableUI/Tests/Internal/ItemCellTests.swift

@@ -30,22 +30,29 @@ class ItemElementCellTests : XCTestCase
 
     func test_sizeThatFits()
     {
-        // The default implementation of size that fits on UIView returns the existing size of the view.
-        // Make sure that value is returned from the cell.
-
-        let cell1 = ItemCell<TestItemContent>(frame: CGRect(origin: .zero, size: CGSize(width: 100.0, height: 100.0)))
-        XCTAssertEqual(cell1.sizeThatFits(.zero), CGSize(width: 100.0, height: 100.0))
-
-        let cell2 = ItemCell<TestItemContent>(frame: CGRect(origin: .zero, size: CGSize(width: 150.0, height: 150.0)))
-        XCTAssertEqual(cell2.sizeThatFits(.zero), CGSize(width: 150.0, height: 150.0))
+        let cell = ItemCell<TestItemContent>(frame: CGRect(origin: .zero, size: CGSize(width: 100.0, height: 100.0)))
+        XCTAssertEqual(cell.sizeThatFits(.zero), CGSize(width: 40.0, height: 50.0))
     }
 
-    func test_systemLayoutSizeFitting() {
-        XCTFail()
+    func test_systemLayoutSizeFitting()
+    {
+        let cell = ItemCell<TestItemContent>(frame: CGRect(origin: .zero, size: CGSize(width: 100.0, height: 100.0)))
+        XCTAssertEqual(cell.systemLayoutSizeFitting(.zero), CGSize(width: 41.0, height: 51.0))
     }
 
-    func test_systemLayoutSizeFitting_withHorizontalFittingPriority_verticalFittingPriority() {
-        XCTFail()
+    func test_systemLayoutSizeFitting_withHorizontalFittingPriority_verticalFittingPriority()
+    {
+        let cell = ItemCell<TestItemContent>(frame: CGRect(origin: .zero, size: CGSize(width: 100.0, height: 100.0)))
+
+        XCTAssertEqual(
+            cell.systemLayoutSizeFitting(
+                .zero,
+                withHorizontalFittingPriority: .required,
+                verticalFittingPriority: .fittingSizeLevel
+            ),
+
+            CGSize(width: 42.0, height: 52.0)
+        )
     }
 }
 
@@ -62,18 +69,74 @@ fileprivate struct TestItemContent : ItemContent, Equatable
     typealias ContentView = UIView
 
     static func createReusableContentView(frame: CGRect) -> UIView {
-        return UIView(frame: frame)
+        return View(frame: frame)
+    }
+
+    private final class View : UIView {
+        override func sizeThatFits(_ size: CGSize) -> CGSize {
+            CGSize(width: 40, height: 50)
+        }
+
+        override func systemLayoutSizeFitting(_ targetSize: CGSize) -> CGSize {
+            CGSize(width: 41, height: 51)
+        }
+
+        override func systemLayoutSizeFitting(
+            _ targetSize: CGSize,
+            withHorizontalFittingPriority horizontalFittingPriority:
+                UILayoutPriority, verticalFittingPriority: UILayoutPriority
+        ) -> CGSize {
+            CGSize(width: 42, height: 52)
+        }
     }
 }
 
 
 class ItemElementCell_LiveCells_Tests : XCTestCase
 {
     func test_add() {
+        let liveCells = LiveCells()
+
+        var cell1 : AnyItemCell? = ItemCell<TestContent>(frame: .zero)
+
+        liveCells.add(cell1!)
 
+        // Should only add the cell once.
+
+        XCTAssertEqual(liveCells.cells.count, 1)
+
+        // Nil out the first cell
+
+        weak var weakCell1 = cell1
+
+        cell1 = nil
+
+        self.waitFor {
+            weakCell1 == nil
+        }
+
+        // Register a second cell, should remove the first
+
+        let cell2 = ItemCell<TestContent>(frame: .zero)
+
+        liveCells.add(cell2)
+
+        XCTAssertEqual(liveCells.cells.count, 1)
+        XCTAssertTrue(liveCells.cells.first?.cell === cell2)
     }
-
-    func test_perform() {
+
+    private struct TestContent : ItemContent, Equatable {
+
+        var identifier: Identifier<TestContent> {
+            .init()
+        }
+
+        static func createReusableContentView(frame: CGRect) -> UIView {
+            UIView(frame: frame)
+        }
 
+        func apply(to views: ItemContentViews<TestContent>, for reason: ApplyReason, with info: ApplyItemContentInfo) {
+            // Nothing needed
+        }
     }
 }

ListableUI/Tests/Internal/SupplementaryItemViewTests.swift → ListableUI/Tests/Internal/SupplementaryContainerViewTests.swift

@@ -29,7 +29,7 @@ class SupplementaryContainerViewTests: XCTestCase
     func test_sizeThatFits()
     {
         let cache = ReusableViewCache()
-        let view = SupplementaryContainerView(frame: CGRect(origin: .zero, size: CGSize(width: 100.0, height: 100.0)))
+        let view = SupplementaryContainerView(frame:.zero)
 
         view.reuseCache = cache
         view.environment = .empty
@@ -38,15 +38,43 @@ class SupplementaryContainerViewTests: XCTestCase
 
         view.headerFooter = self.newHeaderFooter()
 
-        XCTAssertEqual(view.sizeThatFits(.zero), CGSize(width: 100, height: 100))
+        XCTAssertEqual(view.sizeThatFits(.zero), CGSize(width: 50, height: 40))
     }
 
     func test_systemLayoutSizeFitting() {
-        XCTFail()
+        let cache = ReusableViewCache()
+        let view = SupplementaryContainerView(frame:.zero)
+
+        view.reuseCache = cache
+        view.environment = .empty
+
+        XCTAssertEqual(view.sizeThatFits(.zero), .zero)
+
+        view.headerFooter = self.newHeaderFooter()
+
+        XCTAssertEqual(view.systemLayoutSizeFitting(.zero), CGSize(width: 51, height: 41))
     }
 
     func test_systemLayoutSizeFitting_withHorizontalFittingPriority_verticalFittingPriority() {
-        XCTFail()
+        let cache = ReusableViewCache()
+        let view = SupplementaryContainerView(frame:.zero)
+
+        view.reuseCache = cache
+        view.environment = .empty
+
+        XCTAssertEqual(view.sizeThatFits(.zero), .zero)
+
+        view.headerFooter = self.newHeaderFooter()
+
+        XCTAssertEqual(
+            view.systemLayoutSizeFitting(
+                .zero,
+                withHorizontalFittingPriority: .required,
+                verticalFittingPriority: .defaultLow
+            ),
+
+            CGSize(width: 52, height: 42)
+        )
     }
 
     func test_headerFooter()
@@ -71,7 +99,7 @@ class SupplementaryContainerViewTests: XCTestCase
         let content = view.content!
 
         XCTAssertTrue(type(of: content) === HeaderFooterContentView<TestHeaderFooterContent>.self)
-        XCTAssertEqual(view.frame.size, CGSize(width: 100, height: 100))
+        XCTAssertEqual(view.frame.size, CGSize(width: 50, height: 40))
 
         // Unset the header footer, make sure the view is pushed back into the cache.
 
@@ -125,9 +153,20 @@ fileprivate struct TestHeaderFooterContent : HeaderFooterContent, Equatable
 
     final class View : UIView
     {
-        override func sizeThatFits(_ size: CGSize) -> CGSize
-        {
-            return CGSize(width: 100, height: 100)
+        override func sizeThatFits(_ size: CGSize) -> CGSize {
+            CGSize(width: 50, height: 40)
+        }
+
+        override func systemLayoutSizeFitting(_ targetSize: CGSize) -> CGSize {
+            CGSize(width: 51, height: 41)
+        }
+
+        override func systemLayoutSizeFitting(
+            _ targetSize: CGSize,
+            withHorizontalFittingPriority horizontalFittingPriority: UILayoutPriority,
+            verticalFittingPriority: UILayoutPriority
+        ) -> CGSize {
+            CGSize(width: 52, height: 42)
         }
     }
 }