Add ObservedObject implementation

Sources/OpenSwiftUI/DataAndStorage/Internal/Location/ObservableObjectLocation.swift

@@ -0,0 +1,40 @@
+//
+//  ObservableObjectLocation.swift
+//  OpenSwiftUI
+//
+//  Created by Kyle on 2023/11/2.
+//  Lastest Version: iOS 15.5
+//  Status: Blocked by PropertyList.Element
+
+#if OPENSWIFTUI_USE_COMBINE
+import Combine
+#else
+import OpenCombine
+#endif
+internal import OpenSwiftUIShims
+
+struct ObservableObjectLocation<Root, Value>: Location where Root: ObservableObject {
+    let base: Root
+    let keyPath: ReferenceWritableKeyPath<Root, Value>
+
+    var wasRead: Bool {
+        get { true }
+        set {}
+    }
+    func get() -> Value { base[keyPath: keyPath] }
+    // FIXME
+    func set(_ value: Value, transaction: Transaction) {
+        let element = _threadTransactionData().map { Unmanaged<PropertyList.Element>.fromOpaque($0).takeRetainedValue() }
+        let newElement: PropertyList.Element?
+        if let element = transaction.plist.elements {
+            newElement = element.byPrepending(element)
+        } else {
+            newElement = element
+        }
+
+        let data = _threadTransactionData()
+        defer { _setThreadTransactionData(data) }
+        _setThreadTransactionData(newElement.map { Unmanaged.passUnretained($0).toOpaque() })
+        base[keyPath: keyPath] = value
+    }
+}

Sources/OpenSwiftUI/DataAndStorage/Internal/Location/TODO/LocationBox.swift

@@ -14,4 +14,12 @@ class LocationBox<L: Location>: AnyLocation<L.Value> {
     init(location: L) {
         self.location = location
     }
+
+    override func get() -> L.Value {
+        location.get()
+    }
+
+    override func set(_ value: L.Value, transaction: Transaction) {
+        location.set(value, transaction: transaction)
+    }
 }

Sources/OpenSwiftUI/DataAndStorage/Internal/TODO/PropertyList.swift

@@ -49,6 +49,10 @@ extension PropertyList {
         /*@objc*/
         @usableFromInline
         deinit {}
+
+        func byPrepending(_ element: Element?) -> Element {
+            self
+        }
     }
 }
 

Sources/OpenSwiftUI/DataAndStorage/ModelData/State/ObservedObject.swift

@@ -0,0 +1,61 @@
+//
+//  ObservedObject.swift
+//  OpenSwiftUI
+//
+//  Created by Kyle on 2023/11/5.
+//  Lastest Version: iOS 15.5
+//  Status: Blocked by DynamicProperty
+
+#if OPENSWIFTUI_USE_COMBINE
+import Combine
+#else
+import OpenCombine
+#endif
+internal import OpenSwiftUIShims
+
+@propertyWrapper
+@frozen
+public struct ObservedObject<ObjectType> where ObjectType: ObservableObject {
+    @dynamicMemberLookup
+    @frozen
+    public struct Wrapper {
+        let root: ObjectType
+        public subscript<Subject>(dynamicMember keyPath: ReferenceWritableKeyPath<ObjectType, Subject>) -> Binding<Subject> {
+            Binding(root, keyPath: keyPath)
+        }
+    }
+
+    @usableFromInline
+    var _seed = 0
+
+    public var wrappedValue: ObjectType
+
+    @_alwaysEmitIntoClient
+    public init(initialValue: ObjectType) {
+        self.init(wrappedValue: initialValue)
+    }
+
+    public init(wrappedValue: ObjectType) {
+        self.wrappedValue = wrappedValue
+    }
+
+    public var projectedValue: ObservedObject<ObjectType>.Wrapper {
+        .init(root: wrappedValue)
+    }
+}
+
+extension ObservedObject: DynamicProperty {
+    public static func _makeProperty(in _: inout _DynamicPropertyBuffer, container _: _GraphValue<some Any>, fieldOffset _: Int, inputs _: inout _GraphInputs) {
+        // TODO
+    }
+
+    public static var _propertyBehaviors: UInt32 { 2 }
+}
+
+extension Binding {
+    init<ObjectType: ObservableObject>(_ root: ObjectType, keyPath: ReferenceWritableKeyPath<ObjectType, Value>) {
+        let location = ObservableObjectLocation(base: root, keyPath: keyPath)
+        let box = LocationBox(location: location)
+        self.init(value: location.get(), location: box)
+    }
+}

Sources/OpenSwiftUI/Internal/Other/ProtocolDescriptor.swift

@@ -2,6 +2,7 @@ func conformsToProtocol(_ type: Any.Type, _ protocolDescriptor: UnsafeRawPointer
     swiftConformsToProtocol(type, protocolDescriptor) != nil
 }
 
+// FIXME: This kind usage of @_silgen_name is discouraged. But I'm not finding a way to declare or pass Any.Type to C
 @_silgen_name("swift_conformsToProtocol")
 @inline(__always)
 private func swiftConformsToProtocol(_ type: Any.Type,

Sources/OpenSwiftUI/Views/Animations/TODO/Transaction.swift

@@ -7,6 +7,8 @@
 //  Status: Empty
 //  ID: 39EC6D46662E6D7A6963F5C611934B0A
 
+internal import OpenSwiftUIShims
+
 @frozen
 public struct Transaction {
     @usableFromInline
@@ -34,19 +36,19 @@ extension Transaction {
 //    }
 }
 
-//extension Transaction {
+// extension Transaction {
 //    public var isContinuous: Bool {
 //        get
 //        set
 //    }
-//}
+// }
 //
-//extension Transaction {
+// extension Transaction {
 //    public var _scrollViewAnimates: _ScrollViewAnimationMode {
 //        get
 //        set
 //    }
-//}
+// }
 
 protocol TransactionKey {
     associatedtype Value
@@ -56,3 +58,15 @@ protocol TransactionKey {
 private struct AnimationKey: TransactionKey {
     static let defaultValue: Animation? = nil
 }
+
+public func withTransaction<Result>(
+    _ transaction: Transaction,
+    _ body: () throws -> Result
+) rethrows -> Result {
+    try withExtendedLifetime(transaction) {
+        let data = _threadTransactionData()
+        defer { _setThreadTransactionData(data) }
+        _setThreadTransactionData(transaction.plist.elements.map { Unmanaged.passUnretained($0).toOpaque() })
+        return try body()
+    }
+}

Sources/OpenSwiftUIShims/TLS.c

@@ -0,0 +1,20 @@
+//
+//  TLS.c
+//  
+//
+//  Created by Kyle on 2023/11/5.
+//
+
+#include "TLS.h"
+
+static _Thread_local int64_t _perThreadUpdateCount = 0;
+static _Thread_local void * _perThreadTransactionData = NULL;
+static _Thread_local void * _perThreadGeometryProxyData = NULL;
+
+void _setThreadTransactionData(void * data) {
+    _perThreadTransactionData = data;
+}
+
+void * _threadTransactionData(void) {
+    return _perThreadTransactionData;
+}

Sources/OpenSwiftUIShims/include/TLS.h

@@ -0,0 +1,20 @@
+//
+//  TLS.h
+//  
+//
+//  Created by Kyle on 2023/11/5.
+//
+
+#ifndef TLS_h
+#define TLS_h
+
+#include <OpenFoundation/OpenFoundation.h>
+#include <stdio.h>
+
+OF_EXPORT
+void _setThreadTransactionData(void  * _Nullable data);
+
+OF_EXPORT
+void * _Nullable _threadTransactionData(void);
+
+#endif /* TLS_h */