Avoid unsafe extraction in BindingReducer

Examples/CaseStudies/SwiftUICaseStudies/01-GettingStarted-Bindings-Forms.swift

@@ -28,7 +28,7 @@ struct BindingForm {
   }
 
   var body: some Reducer<State, Action> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
     Reduce { state, action in
       switch action {
       case .binding(\.stepCount):

Examples/CaseStudies/SwiftUICaseStudies/01-GettingStarted-FocusState.swift

@@ -26,7 +26,7 @@ struct FocusDemo {
   }
 
   var body: some Reducer<State, Action> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
     Reduce { state, action in
       switch action {
       case .binding:

Examples/CaseStudies/SwiftUICaseStudies/02-SharedState-Onboarding.swift

@@ -110,7 +110,7 @@ private struct BasicsFeature {
     case binding(BindingAction<State>)
   }
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
   }
 }
 
@@ -161,7 +161,7 @@ private struct PersonalInfoFeature {
   }
   @Dependency(\.dismiss) var dismiss
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
   }
 }
 
@@ -217,7 +217,7 @@ private struct TopicsFeature {
   }
   @Dependency(\.dismiss) var dismiss
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
     Reduce { state, action in
       switch action {
       case .alert:

Examples/Integration/Integration/Legacy/BindingLocalTestCase.swift

@@ -77,7 +77,7 @@ private struct Child {
     case onDisappear
   }
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
   }
 }
 

Examples/Integration/Integration/Legacy/LegacyPresentationTestCase.swift

@@ -224,7 +224,7 @@ private enum PresentationTestCase {
     }
     @Dependency(\.dismiss) var dismiss
     var body: some ReducerOf<Self> {
-      BindingReducer()
+      BindingReducer(action: \.binding)
       Reduce<State, Action> { state, action in
         switch action {
         case .binding:

Examples/Integration/Integration/iOS 17/ObservableBindingLocalTest.swift

@@ -79,7 +79,7 @@ private struct Child {
     case onDisappear
   }
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
   }
 }
 

Examples/Integration/Integration/iOS 17/ObservableSharedStateTestCase.swift

@@ -98,10 +98,10 @@ private struct Feature {
   }
   @Dependency(\.defaultAppStorage) var defaults
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
     Reduce<State, Action> { state, action in
       switch action {
-      case .binding(_):
+      case .binding:
         return .none
       case .deleteFileButtonTapped:
         return .run { _ in

Examples/SyncUps/SyncUps/SyncUpForm.swift

@@ -33,7 +33,7 @@ struct SyncUpForm {
   @Dependency(\.uuid) var uuid
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
     Reduce { state, action in
       switch action {
       case .addAttendeeButtonTapped:

Examples/TicTacToe/tic-tac-toe/Sources/LoginCore/LoginCore.swift

@@ -37,7 +37,7 @@ public struct Login: Sendable {
   public init() {}
 
   public var body: some Reducer<State, Action> {
-    BindingReducer(action: \.view)
+    BindingReducer(action: \.view.binding)
     Reduce { state, action in
       switch action {
       case .alert:

Examples/TicTacToe/tic-tac-toe/Sources/NewGameCore/NewGameCore.swift

@@ -22,7 +22,7 @@ public struct NewGame {
   public init() {}
 
   public var body: some Reducer<State, Action> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
     Reduce { state, action in
       switch action {
       case .binding:

Examples/TicTacToe/tic-tac-toe/Sources/TwoFactorCore/TwoFactorCore.swift

@@ -37,7 +37,7 @@ public struct TwoFactor: Sendable {
   public init() {}
 
   public var body: some ReducerOf<Self> {
-    BindingReducer(action: \.view)
+    BindingReducer(action: \.view.binding)
     Reduce { state, action in
       switch action {
       case .alert:

Examples/Todos/Todos/Todo.swift

@@ -15,7 +15,7 @@ struct Todo {
   }
 
   var body: some Reducer<State, Action> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
   }
 }
 

Examples/Todos/Todos/Todos.swift

@@ -39,7 +39,7 @@ struct Todos {
   private enum CancelID { case todoCompletion }
 
   var body: some Reducer<State, Action> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
     Reduce { state, action in
       switch action {
       case .addTodoButtonTapped:

Sources/ComposableArchitecture/Documentation.docc/Articles/Bindings.md

@@ -223,7 +223,7 @@ struct Settings {
   enum Action: BindableAction { /* ... */ }
 
   var body: some Reducer<State, Action> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
   }
 }
 ```
@@ -252,7 +252,7 @@ action for a given key path in the reducer:
 
 ```swift
 var body: some Reducer<State, Action> {
-  BindingReducer()
+  BindingReducer(action: \.binding)
 
   Reduce { state, action in
     switch action
@@ -273,7 +273,7 @@ particular fields:
 
 ```swift
 var body: some Reducer<State, Action> {
-  BindingReducer()
+  BindingReducer(action: \.binding)
     .onChange(of: \.displayName) { oldValue, newValue in
       // Validate display name
     }

Sources/ComposableArchitecture/Documentation.docc/Tutorials/BuildingSyncUps/03-SyncUpForm/SyncUpForm-01-code-0004.swift

@@ -13,7 +13,7 @@ struct SyncUpForm {
   }
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
 
     Reduce { state, action in
       switch action {

Sources/ComposableArchitecture/Documentation.docc/Tutorials/BuildingSyncUps/03-SyncUpForm/SyncUpForm-01-code-0005.swift

@@ -14,7 +14,7 @@ struct SyncUpForm {
   }
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
 
     Reduce { state, action in
       switch action {

Sources/ComposableArchitecture/Documentation.docc/Tutorials/BuildingSyncUps/03-SyncUpForm/SyncUpForm-01-code-0006.swift

@@ -15,7 +15,7 @@ struct SyncUpForm {
   }
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
 
     Reduce { state, action in
       switch action {

Sources/ComposableArchitecture/Documentation.docc/Tutorials/BuildingSyncUps/03-SyncUpForm/SyncUpForm-03-code-0001-previous.swift

@@ -15,7 +15,7 @@ struct SyncUpForm {
   }
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
 
     Reduce { state, action in
       switch action {

Sources/ComposableArchitecture/Documentation.docc/Tutorials/BuildingSyncUps/03-SyncUpForm/SyncUpForm-03-code-0001.swift

@@ -21,7 +21,7 @@ struct SyncUpForm {
   }
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
 
     Reduce { state, action in
       switch action {

Sources/ComposableArchitecture/Documentation.docc/Tutorials/BuildingSyncUps/03-SyncUpForm/SyncUpForm-03-code-0002.swift

@@ -21,7 +21,7 @@ struct SyncUpForm {
   }
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
 
     Reduce { state, action in
       switch action {

Sources/ComposableArchitecture/Documentation.docc/Tutorials/BuildingSyncUps/03-SyncUpForm/SyncUpForm-03-code-0003.swift

@@ -21,7 +21,7 @@ struct SyncUpForm {
   }
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
 
     Reduce { state, action in
       switch action {

Sources/ComposableArchitecture/Documentation.docc/Tutorials/BuildingSyncUps/03-SyncUpForm/TestingSyncUpForm-02-code-0004-previous.swift

@@ -21,7 +21,7 @@ struct SyncUpForm {
   }
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
 
     Reduce { state, action in
       switch action {

Sources/ComposableArchitecture/Documentation.docc/Tutorials/BuildingSyncUps/03-SyncUpForm/TestingSyncUpForm-02-code-0004.swift

@@ -23,7 +23,7 @@ struct SyncUpForm {
   @Dependency(\.uuid) var uuid
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
 
     Reduce { state, action in
       switch action {

Sources/ComposableArchitecture/Documentation.docc/Tutorials/BuildingSyncUps/03-SyncUpForm/TestingSyncUpForm-02-code-0005.swift

@@ -23,7 +23,7 @@ struct SyncUpForm {
   @Dependency(\.uuid) var uuid
 
   var body: some ReducerOf<Self> {
-    BindingReducer()
+    BindingReducer(action: \.binding)
 
     Reduce { state, action in
       switch action {

Sources/ComposableArchitecture/Reducer/Reducers/BindingReducer.swift

@@ -18,7 +18,7 @@ import SwiftUI
 ///   }
 ///
 ///   var body: some ReducerOf<Self> {
-///     BindingReducer()
+///     BindingReducer(action: \.binding)
 ///     Reduce { state, action in
 ///       // Your feature's logic...
 ///     }
@@ -35,47 +35,81 @@ import SwiftUI
 ///   Reduce { state, action in
 ///     // Your feature's logic...
 ///   }
-///   BindingReducer()
+///   BindingReducer(action: \.binding)
 /// }
 /// ```
 ///
 /// If you forget to compose the ``BindingReducer`` into your feature's reducer, then when a binding
 /// is written to it will cause a runtime purple Xcode warning letting you know what needs to be
 /// fixed.
-public struct BindingReducer<State, Action, ViewAction: BindableAction>: Reducer
-where State == ViewAction.State {
+public struct BindingReducer<State, Action>: Reducer {
   @usableFromInline
-  let toViewAction: (Action) -> ViewAction?
+  let toBindingAction: (Action) -> BindingAction<State>?
+
+  @usableFromInline
+  init(internal toBindingAction: @escaping (Action) -> BindingAction<State>?) {
+    self.toBindingAction = toBindingAction
+  }
 
   /// Initializes a reducer that updates bindable state when it receives binding actions.
+  ///
+  /// - Parameter toBindingAction: A case key path to the binding action case.
   @inlinable
-  public init() where Action == ViewAction {
-    self.init(internal: { $0 })
+  public init(action toBindingAction: CaseKeyPath<Action, BindingAction<State>>) {
+    self.init(internal: AnyCasePath(toBindingAction).extract(from:))
   }
 
   @inlinable
-  public init(action toViewAction: CaseKeyPath<Action, ViewAction>) where Action: CasePathable {
-    self.init(internal: { $0[case: toViewAction] })
+  public func reduce(into state: inout State, action: Action) -> Effect<Action> {
+    guard let bindingAction = toBindingAction(action)
+    else { return .none }
+
+    bindingAction.set(&state)
+    return .none
   }
+}
 
+@available(
+  iOS, deprecated: 9999,
+  message: "Pass an explicit case key path, for example: 'BindingReducer(action: \\.binding)'"
+)
+@available(
+  macOS, deprecated: 9999,
+  message: "Pass an explicit case key path, for example: 'BindingReducer(action: \\.binding)'"
+)
+@available(
+  tvOS, deprecated: 9999,
+  message: "Pass an explicit case key path, for example: 'BindingReducer(action: \\.binding)'"
+)
+@available(
+  watchOS, deprecated: 9999,
+  message: "Pass an explicit case key path, for example: 'BindingReducer(action: \\.binding)'"
+)
+extension BindingReducer {
   @inlinable
-  public init(action toViewAction: @escaping (_ action: Action) -> ViewAction?) {
-    self.init(internal: toViewAction)
+  public init() where Action: BindableAction<State> {
+    self.init(internal: AnyCasePath(unsafe: { .binding($0) }).extract(from:))
   }
 
-  @usableFromInline
-  init(internal toViewAction: @escaping (_ action: Action) -> ViewAction?) {
-    self.toViewAction = toViewAction
+  @_disfavoredOverload
+  @inlinable
+  public init<ViewAction: BindableAction<State>>(
+    action toViewAction: CaseKeyPath<Action, ViewAction>
+  ) {
+    self.init(
+      internal: AnyCasePath(toViewAction)
+        .appending(path: AnyCasePath(unsafe: { .binding($0) }))
+        .extract(from:)
+    )
   }
 
+  @_disfavoredOverload
   @inlinable
-  public func reduce(into state: inout State, action: Action) -> Effect<Action> {
-    // NB: Using a closure and not a `\.binding` key path literal to avoid a bug with archives:
-    //     https://github.com/pointfreeco/swift-composable-architecture/pull/2641
-    guard let bindingAction = self.toViewAction(action).flatMap({ $0.binding })
-    else { return .none }
-
-    bindingAction.set(&state)
-    return .none
+  public init<ViewAction: BindableAction<State>>(
+    action toViewAction: @escaping (_ action: Action) -> ViewAction?
+  ) {
+    let toBindingAction = AnyCasePath<ViewAction, BindingAction<State>>(unsafe: { .binding($0) })
+      .extract(from:)
+    self.init(internal: { toViewAction($0).flatMap(toBindingAction) })
   }
 }

Sources/ComposableArchitecture/Reducer/Reducers/OnChange.swift

@@ -18,7 +18,7 @@ extension Reducer {
   ///   }
   ///
   ///   var body: some Reducer<State, Action> {
-  ///     BindingReducer()
+  ///     BindingReducer(action: \.binding)
   ///       .onChange(
   ///         of: { ($0.userSettings.isHapticFeedbackEnabled, $0.userSettings.isPushEnabled) },
   ///         removeDuplicates: ==
@@ -83,7 +83,7 @@ extension Reducer {
   ///   }
   ///
   ///   var body: some Reducer<State, Action> {
-  ///     BindingReducer()
+  ///     BindingReducer(action: \.binding)
   ///       .onChange(of: \.userSettings.isHapticFeedbackEnabled) { oldValue, newValue in
   ///         Reduce { state, action in
   ///           .run { send in