Add EnvironmentalView

Package.swift

@@ -20,6 +20,7 @@ func envEnable(_ key: String, default defaultValue: Bool = false) -> Bool {
 var sharedSwiftSettings: [SwiftSetting] = [
     .enableUpcomingFeature("BareSlashRegexLiterals"),
     .enableUpcomingFeature("InternalImportsByDefault"),
+    .enableUpcomingFeature("InferSendableFromCaptures"),
     .define("OPENSWIFTUI_SUPPRESS_DEPRECATED_WARNINGS"),
     .swiftLanguageMode(.v5),
 ]
@@ -74,7 +75,11 @@ if development {
 
 let warningsAsErrorsCondition = envEnable("OPENSWIFTUI_WERROR", default: isXcodeEnv && development)
 if warningsAsErrorsCondition {
-   sharedSwiftSettings.append(.unsafeFlags(["-warnings-as-errors"]))
+    // Hold off the werror feature as we can't avoid the concurrency warning.
+    // Reenable the folllowing after swift-evolution#443 is release.
+
+    // sharedSwiftSettings.append(.unsafeFlags(["-warnings-as-errors"]))
+    // sharedSwiftSettings.append(.unsafeFlags(["-Wwarning", "concurrency"]))
 }
 
 // NOTE:

Sources/OpenSwiftUICore/Data/Environment/EnvironmentValues.swift

@@ -150,6 +150,9 @@ public struct EnvironmentValues: CustomStringConvertible {
     private var _plist: PropertyList
     private let tracker: PropertyList.Tracker?
 
+    // FIXME
+    var plist: PropertyList { _plist }
+
     init(plist: PropertyList) {
         _plist = plist
         tracker = nil

Sources/OpenSwiftUICore/Data/Environment/EnvironmentalView.swift

@@ -3,15 +3,97 @@
 //  OpenSwiftUICore
 //
 //  Audited for iOS 18.0
-//  Status: WIP
+//  Status: Blocked by Tracing
 
+import OpenGraphShims
+
+// MARK: - EnvironmentalView
+
+@MainActor
+@preconcurrency
 package protocol EnvironmentalView: PrimitiveView, UnaryView {
     associatedtype EnvironmentBody: View
     func body(environment: EnvironmentValues) -> EnvironmentBody
 }
 
 extension EnvironmentalView {
     nonisolated public static func _makeView(view: _GraphValue<Self>, inputs: _ViewInputs) -> _ViewOutputs {
-        preconditionFailure("")
+        let child = EnvironmentalViewChild(view: view.value, env: inputs.environment)
+        return EnvironmentBody.makeDebuggableView(view: _GraphValue(child), inputs: inputs)
+    }
+}
+
+// MARK: - EnvironmentalViewChild
+
+struct EnvironmentalViewChild<V>: StatefulRule, AsyncAttribute, CustomStringConvertible where V: EnvironmentalView {
+    @Attribute var view: V
+    @Attribute var env: EnvironmentValues
+    let tracker: PropertyList.Tracker
+
+    init(view: Attribute<V>, env: Attribute<EnvironmentValues>) {
+        _view = view
+        _env = env
+        tracker = .init()
+    }
+
+    typealias Value = V.EnvironmentBody
+
+    func updateValue() {
+        let (view, viewChanged) = $view.changedValue()
+        let (env, envChanged) = $env.changedValue()
+
+        let shouldReset: Bool
+        if viewChanged {
+            shouldReset = true
+        } else if envChanged, tracker.hasDifferentUsedValues(env.plist) {
+            shouldReset = true
+        } else {
+            // TODO: Optimize this API call
+            let outputValue: UnsafePointer<V.EnvironmentBody>? = Graph.outputValue()
+            shouldReset = outputValue == nil
+        }
+        guard shouldReset else { return }
+        tracker.reset()
+        tracker.initializeValues(from: env.plist)
+        // TODO: Tracing
+        value = view.body(environment: env)
+    }
+
+    var description: String {
+        "EnvironmentReading: \(V.self)"
+    }
+}
+
+// MARK: - EnvironmentReader
+
+@MainActor
+@preconcurrency
+package struct EnvironmentReader<Content>: EnvironmentalView where Content: View {
+    let content: (EnvironmentValues) -> Content
+
+    package init(@ViewBuilder _ content: @escaping (EnvironmentValues) -> Content) {
+        self.content = content
+    }
+
+    package func body(environment: EnvironmentValues) -> Content {
+        content(environment)
+    }
+
+    nonisolated package static func _makeViewList(view: _GraphValue<Self>, inputs: _ViewListInputs) -> _ViewListOutputs {
+        guard Semantics.EnvironmentReaderViewIsMulti.isEnabled else {
+            return _ViewListOutputs.unaryViewList(view: view, inputs: inputs)
+        }
+        let child = EnvironmentalViewChild(view: view.value, env: inputs.base.environment)
+        return EnvironmentBody.makeDebuggableViewList(view: _GraphValue(child), inputs: inputs)
+    }
+
+    nonisolated package static func _viewListCount(inputs: _ViewListCountInputs) -> Int? {
+        guard Semantics.EnvironmentReaderViewIsMulti.isEnabled else {
+            return 1
+        }
+        return Content._viewListCount(inputs: inputs)
     }
+
+    package typealias Body = Never
+    package typealias EnvironmentBody = Content
 }

Sources/OpenSwiftUICore/Graph/GraphValue.swift

@@ -42,7 +42,6 @@ public struct _GraphValue<Value>: Equatable {
 
     package func unsafeBitCast<T>(to _: T.Type) -> _GraphValue<T> {
         _GraphValue<T>(value.unsafeBitCast(to: T.self))
-
     }
 
     public static func == (a: _GraphValue<Value>, b: _GraphValue<Value>) -> Bool {

Sources/OpenSwiftUICore/Modifier/ModifiedContent.swift

@@ -7,7 +7,7 @@
 
 extension View {
     @inlinable
-    public func modifier<T>(_ modifier: T) -> ModifiedContent<Self, T> {
+    nonisolated public func modifier<T>(_ modifier: T) -> ModifiedContent<Self, T> {
         .init(content: self, modifier: modifier)
     }
 }

Sources/OpenSwiftUICore/Modifier/ViewModifier/TODO/_EnvironmentKeyWritingModifier.swift

@@ -6,12 +6,11 @@
 //  Status: WIP
 
 @frozen
-public struct _EnvironmentKeyWritingModifier<Value>: ViewModifier/*, _GraphInputsModifier*/ {
+public struct _EnvironmentKeyWritingModifier<Value>: ViewModifier, _GraphInputsModifier, PrimitiveViewModifier {
     public var keyPath: WritableKeyPath<EnvironmentValues, Value>
     public var value: Value
 
     @inlinable
-    @inline(__always)
     public init(keyPath: WritableKeyPath<EnvironmentValues, Value>, value: Value) {
         self.keyPath = keyPath
         self.value = value
@@ -20,12 +19,16 @@ public struct _EnvironmentKeyWritingModifier<Value>: ViewModifier/*, _GraphInput
     public static func _makeInputs(modifier: _GraphValue<_EnvironmentKeyWritingModifier<Value>>, inputs: inout _GraphInputs) {
         // TODO
     }
+
+
 }
 
+@available(*, unavailable)
+extension _EnvironmentKeyWritingModifier: Sendable {}
+
 extension View {
     @inlinable
-    @inline(__always)
-    public func environment<V>(_ keyPath: WritableKeyPath<EnvironmentValues, V>, _ value: V) -> some View {
+    nonisolated public func environment<V>(_ keyPath: WritableKeyPath<EnvironmentValues, V>, _ value: V) -> some View {
         modifier(_EnvironmentKeyWritingModifier<V>(keyPath: keyPath, value: value))
     }
 }

Sources/OpenSwiftUICore/Modifier/ViewModifier/ViewModifier.swift

@@ -1,6 +1,6 @@
 //
 //  ViewModifier.swift
-//  OpenSwiftUI
+//  OpenSwiftUICore
 //
 //  Audited for iOS 15.5
 //  Status: Complete
@@ -48,68 +48,45 @@
 /// Downtown Bus. A view extension, using custom a modifier, renders the
 ///  caption in blue text surrounded by a rounded
 ///  rectangle.](OpenSwiftUI-View-ViewModifier.png)
+@MainActor
+@preconcurrency
 public protocol ViewModifier {
-    /// The type of view representing the body.
-    associatedtype Body: View
-
     /// Makes a new view using the view modifier and inputs that you provide.
-    static func _makeView(
+    nonisolated static func _makeView(
         modifier: _GraphValue<Self>,
         inputs: _ViewInputs,
         body: @escaping (_Graph, _ViewInputs) -> _ViewOutputs
     ) -> _ViewOutputs
 
-    static func _makeViewList(
+    nonisolated static func _makeViewList(
         modifier: _GraphValue<Self>,
         inputs: _ViewListInputs,
         body: @escaping (_Graph, _ViewListInputs) -> _ViewListOutputs
     ) -> _ViewListOutputs
 
     /// The number of views that `_makeViewList()` would produce, or
     /// nil if unknown.
-    static func _viewListCount(
+    nonisolated static func _viewListCount(
         inputs: _ViewListCountInputs,
         body: (_ViewListCountInputs) -> Int?
     ) -> Int?
 
-    /// The content view type passed to `body()`.
-    typealias Content = _ViewModifier_Content<Self>
+    /// The type of view representing the body.
+    associatedtype Body: View
 
     /// Gets the current body of the caller.
     ///
     /// `content` is a proxy for the view that will have the modifier
     /// represented by `Self` applied to it.
     @ViewBuilder
-    @MainActor
-    @preconcurrency
     func body(content: Content) -> Body
-}
-
-extension ViewModifier {
-    public static func _makeView(
-        modifier: _GraphValue<Self>,
-        inputs: _ViewInputs,
-        body: @escaping (_Graph, _ViewInputs) -> _ViewOutputs
-    ) -> _ViewOutputs {
-        makeView(modifier: modifier, inputs: inputs, body: body)
-    }
 
-    public static func _makeViewList(
-        modifier: _GraphValue<Self>,
-        inputs: _ViewListInputs,
-        body: @escaping (_Graph, _ViewListInputs) -> _ViewListOutputs
-    ) -> _ViewListOutputs {
-        makeViewList(modifier: modifier, inputs: inputs, body: body)
-    }
-
-    public static func _viewListCount(
-        inputs: _ViewListCountInputs,
-        body: (_ViewListCountInputs) -> Int?
-    ) -> Int? {
-        viewListCount(inputs: inputs, body: body)
-    }
+    /// The content view type passed to `body()`.
+    typealias Content = _ViewModifier_Content<Self>
 }
 
+package protocol PrimitiveViewModifier: ViewModifier where Body == Never {}
+
 extension ViewModifier where Body == Never {
     public func body(content _: Content) -> Never {
         bodyError()
@@ -163,3 +140,28 @@ extension ViewModifier {
         preconditionFailure("body() should not be called on \(Self.self)")
     }
 }
+
+extension ViewModifier {
+    public static func _makeView(
+        modifier: _GraphValue<Self>,
+        inputs: _ViewInputs,
+        body: @escaping (_Graph, _ViewInputs) -> _ViewOutputs
+    ) -> _ViewOutputs {
+        makeView(modifier: modifier, inputs: inputs, body: body)
+    }
+
+    public static func _makeViewList(
+        modifier: _GraphValue<Self>,
+        inputs: _ViewListInputs,
+        body: @escaping (_Graph, _ViewListInputs) -> _ViewListOutputs
+    ) -> _ViewListOutputs {
+        makeViewList(modifier: modifier, inputs: inputs, body: body)
+    }
+
+    public static func _viewListCount(
+        inputs: _ViewListCountInputs,
+        body: (_ViewListCountInputs) -> Int?
+    ) -> Int? {
+        viewListCount(inputs: inputs, body: body)
+    }
+}

Sources/OpenSwiftUICore/View/AnyView.swift

@@ -1,20 +1,25 @@
 //
 //  AnyView.swift
-//  OpenSwiftUI
+//  OpenSwiftUICore
 //
-//  Audited for iOS 15.5
+//  Audited for iOS 18.0
 //  Status: WIP
-//  ID: A96961F3546506F21D8995C6092F15B5
+//  ID: A96961F3546506F21D8995C6092F15B5 (OpenSwiftUI)
+//  ID: 7578D05D331D7F1A2E0C2F8DEF38AAD4 (OpenSwiftUICore)
 
 import OpenGraphShims
 import OpenSwiftUI_SPI
 
 @frozen
-public struct AnyView: PrimitiveView {
+public struct AnyView: View, PrimitiveView {
     var storage: AnyViewStorageBase
 
     public init<V>(_ view: V) where V: View {
-        self.init(view, id: nil)
+        if let anyView = view as? AnyView {
+            storage = anyView.storage
+        } else {
+            storage = AnyViewStorage(view: view)
+        }
     }
 
     @_alwaysEmitIntoClient
@@ -42,19 +47,7 @@ public struct AnyView: PrimitiveView {
         }
         self = visitor.view!
     }
-
-    init<V: View>(_ view: V, id: UniqueID?) {
-        if let anyView = view as? AnyView {
-            storage = anyView.storage
-        } else {
-            storage = AnyViewStorage(view: view, id: id)
-        }
-    }
-
-    func visitContent<Visitor: ViewVisitor>(_ visitor: inout Visitor) {
-        storage.visitContent(&visitor)
-    }
-
+
     public static func _makeView(view: _GraphValue<Self>, inputs: _ViewInputs) -> _ViewOutputs {
         #if canImport(Darwin)
         let outputs = inputs.makeIndirectOutputs()
@@ -76,16 +69,14 @@ public struct AnyView: PrimitiveView {
     public static func _makeViewList(view: _GraphValue<Self>, inputs: _ViewListInputs) -> _ViewListOutputs {
         preconditionFailure("TODO")
     }
+
+    package func visitContent<Visitor: ViewVisitor>(_ visitor: inout Visitor) {
+        storage.visitContent(&visitor)
+    }
 }
 
 @usableFromInline
 class AnyViewStorageBase {
-    let id: UniqueID?
-
-    init(id: UniqueID?) {
-        self.id = id
-    }
-
     fileprivate var type: Any.Type { preconditionFailure("") }
     fileprivate var canTransition: Bool { preconditionFailure("") }
     fileprivate func matches(_ other: AnyViewStorageBase) -> Bool { preconditionFailure("") }
@@ -111,10 +102,13 @@ class AnyViewStorageBase {
 private final class AnyViewStorage<V: View>: AnyViewStorageBase {
     let view: V
 
-    init(view: V, id: UniqueID?) {
+    init(view: V) {
         self.view = view
-        super.init(id: id)
+        super.init()
     }
+
+    // FIXME
+    var id: UniqueID? { nil }
 
     override var type: Any.Type { V.self }