Update VariadicView_Children

Sources/OpenSwiftUICore/View/VariadicView_Children.swift → Sources/OpenSwiftUICore/View/Input/ViewListView.swift

@@ -1,5 +1,5 @@
 //
-//  VariadicView_Children.swift
+//  ViewListView.swift
 //  OpenSwiftUICore
 //
 //  Audited for 6.0.87
@@ -9,77 +9,6 @@
 
 package import OpenAttributeGraphShims
 
-// MARK: - _VariadicView.Children + View [WIP]
-
-@available(OpenSwiftUI_v1_0, *)
-extension _VariadicView.Children: View, MultiView, PrimitiveView {
-    nonisolated public static func _makeViewList(
-        view: _GraphValue<Self>,
-        inputs: _ViewListInputs
-    ) -> _ViewListOutputs {
-        let child = _GraphValue(Child(children: view.value))
-        return ForEach._makeViewList(view: child, inputs: inputs)
-    }
-
-    @available(OpenSwiftUI_v2_0, *)
-    nonisolated public static func _viewListCount(
-        inputs: _ViewListCountInputs
-    ) -> Int? {
-        nil
-    }
-
-    private struct Child: Rule, AsyncAttribute {
-        typealias Value = ForEach<_VariadicView.Children, AnyHashable, _VariadicView.Children.Element>
-
-        @Attribute var children: _VariadicView.Children
-
-        var value: Value {
-            _openSwiftUIUnimplementedFailure()
-        }
-    }
-}
-
-// MARK: - _VariadicView.Children + RandomAccessCollection [WIP]
-
-@available(OpenSwiftUI_v1_0, *)
-extension _VariadicView.Children: RandomAccessCollection {
-    public struct Element: PrimitiveView, UnaryView, Identifiable {
-        var view: ViewList.View
-        var traits: ViewTraitCollection
-
-        public var id: AnyHashable {
-            _openSwiftUIUnimplementedFailure()
-
-        }
-        public func id<ID>(as _: ID.Type = ID.self) -> ID? where ID : Hashable {
-            _openSwiftUIUnimplementedFailure()
-        }
-
-        /// The value of each trait associated with the view. Changing
-        /// the traits will not affect the view in any way.
-        public subscript<Trait: _ViewTraitKey>(key: Trait.Type) -> Trait.Value {
-            get { traits[key] }
-            set { traits[key] = newValue }
-        }
-
-        public static func _makeView(view: _GraphValue<Self>, inputs: _ViewInputs) -> _ViewOutputs {
-            _openSwiftUIUnimplementedFailure()
-        }
-    }
-
-    public var startIndex: Int {
-        _openSwiftUIUnimplementedFailure()
-    }
-
-    public var endIndex: Int {
-        _openSwiftUIUnimplementedFailure()
-    }
-
-    public subscript(index: Int) -> Element {
-        _openSwiftUIUnimplementedFailure()
-    }
-}
-
 // MARK: - ViewListVisitor
 
 package protocol ViewListVisitor {
@@ -142,6 +71,16 @@ package struct _ViewList_View: PrimitiveView, View, UnaryView {
     var count: Int
     var contentSubgraph: Subgraph?
 
+    @inline(__always)
+    init(emptyViewID implicitID: Int) {
+        self.elements = EmptyViewListElements()
+        self.releaseElements = nil
+        self.id = .init(implicitID: implicitID)
+        self.index = .zero
+        self.count = .zero
+        self.contentSubgraph = nil
+    }
+
     package init(
         elements: any ViewList.Elements,
         id: ViewList.ID,
@@ -150,6 +89,7 @@ package struct _ViewList_View: PrimitiveView, View, UnaryView {
         contentSubgraph: Subgraph
     ) {
         self.elements = elements
+        releaseElements = elements.retain()
         self.id = id
         self.index = index
         self.count = count

Sources/OpenSwiftUICore/View/VariadicView/VariadicViewChildren.swift

@@ -0,0 +1,112 @@
+//
+//  VariadicViewChildren.swift
+//  OpenSwiftUICore
+//
+//  Audited for 6.5.4
+//  Status: Complete
+
+import OpenAttributeGraphShims
+
+// MARK: - _VariadicView.Children + View
+
+@available(OpenSwiftUI_v1_0, *)
+extension _VariadicView.Children: View, MultiView, PrimitiveView {
+    nonisolated public static func _makeViewList(
+        view: _GraphValue<Self>,
+        inputs: _ViewListInputs
+    ) -> _ViewListOutputs {
+        let child = _GraphValue(Child(children: view.value))
+        return ForEach._makeViewList(view: child, inputs: inputs)
+    }
+
+    @available(OpenSwiftUI_v2_0, *)
+    nonisolated public static func _viewListCount(
+        inputs: _ViewListCountInputs
+    ) -> Int? {
+        nil
+    }
+
+    private struct Child: Rule, AsyncAttribute {
+        typealias Value = ForEach<_VariadicView.Children, AnyHashable, _VariadicView.Children.Element>
+
+        @Attribute var children: _VariadicView.Children
+
+        var value: Value {
+            ForEach(children) { $0 }
+        }
+    }
+}
+
+// MARK: - _VariadicView.Children + RandomAccessCollection
+
+@available(OpenSwiftUI_v1_0, *)
+extension _VariadicView.Children: RandomAccessCollection {
+
+    public struct Element: PrimitiveView, UnaryView, Identifiable {
+        var view: ViewList.View
+        var traits: ViewTraitCollection
+
+        public var id: AnyHashable {
+            view.viewID
+        }
+
+        public func id<ID>(as _: ID.Type = ID.self) -> ID? where ID: Hashable {
+            view.id.primaryExplicitID.flatMap{ $0.as(type: ID.self) }
+        }
+
+        /// The value of each trait associated with the view. Changing
+        /// the traits will not affect the view in any way.
+        public subscript<Trait: _ViewTraitKey>(key: Trait.Type) -> Trait.Value {
+            get { traits[key] }
+            set { traits[key] = newValue }
+        }
+
+        public static func _makeView(view: _GraphValue<Self>, inputs: _ViewInputs) -> _ViewOutputs {
+            ViewList.View._makeView(
+                view: view[\.view],
+                inputs: inputs
+            )
+        }
+    }
+
+    public var startIndex: Int { .zero }
+
+    public var endIndex: Int { Update.ensure { list.count } }
+
+    public subscript(index: Int) -> Element {
+        var element: Element?
+        Update.ensure {
+            var start = index
+            var transform = transform
+            list.applySublists(
+                from: &start,
+                list: nil,
+                transform: &transform
+            ) { sublist in
+                let index = sublist.start
+                let count = sublist.count
+                if index < count {
+                    element = Element(
+                        view: .init(
+                            elements: sublist.elements,
+                            id: sublist.id,
+                            index: index,
+                            count: count,
+                            contentSubgraph: contentSubgraph
+                        ),
+                        traits: sublist.traits
+                    )
+                }
+                return index >= count
+            }
+        }
+        guard let element else {
+            Log.internalError("Accessing invalid variadic view child at index %d", index)
+            return Element(
+                view: .init(emptyViewID: index),
+                traits: .init()
+            )
+        }
+        return element
+    }
+}