Rename BindableState to BindingState (#1855)

The -`able` naming evokes protocols in Swift, and is an outlier when
considered alongside the rest of TCA's binding tools:

- `BindingAction`: concrete type
- `BindableAction`: protocol
- `BindingReducer`: concrete type

So, let's make things consistent.

The one caveat is that Swift diagnostics for such a deprecation aren't
great, so users won't get proactive warnings here for the time being:

swiftlang/swift#63139

We may just want to keep the deprecation around till it does...

Author: stephencelis

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

@@ -8,7 +8,7 @@ private let readMe = """
   Bindable state and actions allow you to safely eliminate the boilerplate caused by needing to \
   have a unique action for every UI control. Instead, all UI bindings can be consolidated into a \
   single `binding` action that holds onto a `BindingAction` value, and all bindable state can be \
-  safeguarded with the `BindableState` property wrapper.
+  safeguarded with the `BindingState` property wrapper.
 
   It is instructive to compare this case study to the "Binding Basics" case study.
   """
@@ -17,10 +17,10 @@ private let readMe = """
 
 struct BindingForm: ReducerProtocol {
   struct State: Equatable {
-    @BindableState var sliderValue = 5.0
-    @BindableState var stepCount = 10
-    @BindableState var text = ""
-    @BindableState var toggleIsOn = false
+    @BindingState var sliderValue = 5.0
+    @BindingState var stepCount = 10
+    @BindingState var text = ""
+    @BindingState var toggleIsOn = false
   }
 
   enum Action: BindableAction, Equatable {

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

@@ -10,9 +10,9 @@ private let readMe = """
 
 struct FocusDemo: ReducerProtocol {
   struct State: Equatable {
-    @BindableState var focusedField: Field?
-    @BindableState var password: String = ""
-    @BindableState var username: String = ""
+    @BindingState var focusedField: Field?
+    @BindingState var password: String = ""
+    @BindingState var username: String = ""
 
     enum Field: String, Hashable {
       case username, password

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

@@ -177,20 +177,20 @@ struct Settings: ReducerProtocol {
 ```
 
 This is a _lot_ of boilerplate for something that should be simple. Luckily, we can dramatically
-eliminate this boilerplate using ``BindableState``, ``BindableAction``, and ``BindingReducer``.
+eliminate this boilerplate using ``BindingState``, ``BindableAction``, and ``BindingReducer``.
 
-First, we can annotate each bindable value of state with the ``BindableState`` property wrapper:
+First, we can annotate each bindable value of state with the ``BindingState`` property wrapper:
 
 ```swift
 struct Settings: ReducerProtocol {
   struct State: Equatable {
-    @BindableState var digest = Digest.daily
-    @BindableState var displayName = ""
-    @BindableState var enableNotifications = false
+    @BindingState var digest = Digest.daily
+    @BindingState var displayName = ""
+    @BindingState var enableNotifications = false
     var isLoading = false
-    @BindableState var protectMyPosts = false
-    @BindableState var sendEmailNotifications = false
-    @BindableState var sendMobileNotifications = false
+    @BindingState var protectMyPosts = false
+    @BindingState var sendEmailNotifications = false
+    @BindingState var sendMobileNotifications = false
   }
 
   // ...

Sources/ComposableArchitecture/Documentation.docc/Extensions/SwiftUI.md

@@ -19,7 +19,7 @@ The Composable Architecture can be used to power applications built in many fram
 
 - <doc:Bindings>
 - ``ViewStore/binding(get:send:)-65xes``
-- ``BindableState``
+- ``BindingState``
 - ``BindableAction``
 - ``BindingAction``
 - ``BindingReducer``

Sources/ComposableArchitecture/Internal/Deprecations.swift

@@ -3,6 +3,14 @@ import Combine
 import SwiftUI
 import XCTestDynamicOverlay
 
+// MARK: - Deprecated after 0.49.2
+
+// NB: As of Swift 5.7, property wrapper deprecations are not diagnosed, so we may want to keep this
+//     deprecation around for now:
+//     https://github.com/apple/swift/issues/63139
+@available(*, deprecated, renamed: "BindingState")
+public typealias BindableState = BindingState
+
 // MARK: - Deprecated after 0.47.2
 
 extension ActorIsolated {
@@ -972,7 +980,7 @@ extension ViewStore where ViewAction: BindableAction, ViewAction.State == ViewSt
   )
   @MainActor
   public subscript<Value: Equatable>(
-    dynamicMember keyPath: WritableKeyPath<ViewState, BindableState<Value>>
+    dynamicMember keyPath: WritableKeyPath<ViewState, BindingState<Value>>
   ) -> Binding<Value> {
     self.binding(
       get: { $0[keyPath: keyPath].wrappedValue },
@@ -988,8 +996,8 @@ extension BindingAction {
     *, deprecated,
     message:
       """
-      For improved safety, bindable properties must now be wrapped explicitly in 'BindableState', \
-      and accessed via key paths to that 'BindableState', like '\\.$value'
+      For improved safety, bindable properties must now be wrapped explicitly in 'BindingState', \
+      and accessed via key paths to that 'BindingState', like '\\.$value'
       """
   )
   public static func set<Value: Equatable>(
@@ -1008,8 +1016,8 @@ extension BindingAction {
     *, deprecated,
     message:
       """
-      For improved safety, bindable properties must now be wrapped explicitly in 'BindableState', \
-      and accessed via key paths to that 'BindableState', like '\\.$value'
+      For improved safety, bindable properties must now be wrapped explicitly in 'BindingState', \
+      and accessed via key paths to that 'BindingState', like '\\.$value'
       """
   )
   public static func ~= <Value>(
@@ -1042,8 +1050,8 @@ extension ViewStore {
     *, deprecated,
     message:
       """
-      For improved safety, bindable properties must now be wrapped explicitly in 'BindableState'. \
-      Bindings are now derived via 'ViewStore.binding' with a key path to that 'BindableState' \
+      For improved safety, bindable properties must now be wrapped explicitly in 'BindingState'. \
+      Bindings are now derived via 'ViewStore.binding' with a key path to that 'BindingState' \
       (for example, 'viewStore.binding(\\.$value)'). For dynamic member lookup to be available, \
       the view store's 'Action' type must also conform to 'BindableAction'.
       """

Sources/ComposableArchitecture/SwiftUI/Binding.swift

@@ -11,7 +11,7 @@ import SwiftUI
 /// Read <doc:Bindings> for more information.
 @dynamicMemberLookup
 @propertyWrapper
-public struct BindableState<Value> {
+public struct BindingState<Value> {
   /// The underlying value wrapped by the bindable state.
   public var wrappedValue: Value
 
@@ -23,13 +23,13 @@ public struct BindableState<Value> {
   /// A projection that can be used to derive bindings from a view store.
   ///
   /// Use the projected value to derive bindings from a view store with properties annotated with
-  /// `@BindableState`. To get the `projectedValue`, prefix the property with `$`:
+  /// `@BindingState`. To get the `projectedValue`, prefix the property with `$`:
   ///
   /// ```swift
   /// TextField("Display name", text: viewStore.binding(\.$displayName))
   /// ```
   ///
-  /// See ``BindableState`` for more details.
+  /// See ``BindingState`` for more details.
   public var projectedValue: Self {
     get { self }
     set { self = newValue }
@@ -41,17 +41,17 @@ public struct BindableState<Value> {
   /// - Returns: A new bindable state.
   public subscript<Subject>(
     dynamicMember keyPath: WritableKeyPath<Value, Subject>
-  ) -> BindableState<Subject> {
+  ) -> BindingState<Subject> {
     get { .init(wrappedValue: self.wrappedValue[keyPath: keyPath]) }
     set { self.wrappedValue[keyPath: keyPath] = newValue.wrappedValue }
   }
 }
 
-extension BindableState: Equatable where Value: Equatable {}
+extension BindingState: Equatable where Value: Equatable {}
 
-extension BindableState: Hashable where Value: Hashable {}
+extension BindingState: Hashable where Value: Hashable {}
 
-extension BindableState: Decodable where Value: Decodable {
+extension BindingState: Decodable where Value: Decodable {
   public init(from decoder: Decoder) throws {
     do {
       let container = try decoder.singleValueContainer()
@@ -62,7 +62,7 @@ extension BindableState: Decodable where Value: Decodable {
   }
 }
 
-extension BindableState: Encodable where Value: Encodable {
+extension BindingState: Encodable where Value: Encodable {
   public func encode(to encoder: Encoder) throws {
     do {
       var container = encoder.singleValueContainer()
@@ -73,29 +73,29 @@ extension BindableState: Encodable where Value: Encodable {
   }
 }
 
-extension BindableState: CustomReflectable {
+extension BindingState: CustomReflectable {
   public var customMirror: Mirror {
     Mirror(reflecting: self.wrappedValue)
   }
 }
 
-extension BindableState: CustomDumpRepresentable {
+extension BindingState: CustomDumpRepresentable {
   public var customDumpValue: Any {
     self.wrappedValue
   }
 }
 
-extension BindableState: CustomDebugStringConvertible where Value: CustomDebugStringConvertible {
+extension BindingState: CustomDebugStringConvertible where Value: CustomDebugStringConvertible {
   public var debugDescription: String {
     self.wrappedValue.debugDescription
   }
 }
 
-extension BindableState: Sendable where Value: Sendable {}
+extension BindingState: Sendable where Value: Sendable {}
 
 /// An action type that exposes a `binding` case that holds a ``BindingAction``.
 ///
-/// Used in conjunction with ``BindableState`` to safely eliminate the boilerplate typically
+/// Used in conjunction with ``BindingState`` to safely eliminate the boilerplate typically
 /// associated with mutating multiple fields in state.
 ///
 /// Read <doc:Bindings> for more information.
@@ -116,7 +116,7 @@ extension BindableAction {
   ///
   /// - Returns: A binding action.
   public static func set<Value: Equatable>(
-    _ keyPath: WritableKeyPath<State, BindableState<Value>>,
+    _ keyPath: WritableKeyPath<State, BindingState<Value>>,
     _ value: Value
   ) -> Self {
     self.binding(.set(keyPath, value))
@@ -129,7 +129,7 @@ extension ViewStore where ViewAction: BindableAction, ViewAction.State == ViewSt
   /// - Parameter keyPath: A key path to a specific bindable state.
   /// - Returns: A new binding.
   public func binding<Value: Equatable>(
-    _ keyPath: WritableKeyPath<ViewState, BindableState<Value>>,
+    _ keyPath: WritableKeyPath<ViewState, BindingState<Value>>,
     file: StaticString = #file,
     fileID: StaticString = #fileID,
     line: UInt = #line
@@ -157,7 +157,7 @@ extension ViewStore where ViewAction: BindableAction, ViewAction.State == ViewSt
 
 /// An action that describes simple mutations to some root state at a writable key path.
 ///
-/// Used in conjunction with ``BindableState`` and ``BindableAction`` to safely eliminate the
+/// Used in conjunction with ``BindingState`` and ``BindableAction`` to safely eliminate the
 /// boilerplate typically associated with mutating multiple fields in state.
 ///
 /// Read <doc:Bindings> for more information.
@@ -180,12 +180,12 @@ extension BindingAction {
   ///
   /// - Parameters:
   ///   - keyPath: A key path to the property that should be mutated. This property must be
-  ///     annotated with the ``BindableState`` property wrapper.
+  ///     annotated with the ``BindingState`` property wrapper.
   ///   - value: A value to assign at the given key path.
   /// - Returns: An action that describes simple mutations to some root state at a writable key
   ///   path.
   public static func set<Value: Equatable>(
-    _ keyPath: WritableKeyPath<Root, BindableState<Value>>,
+    _ keyPath: WritableKeyPath<Root, BindingState<Value>>,
     _ value: Value
   ) -> Self {
     return .init(
@@ -208,14 +208,14 @@ extension BindingAction {
   ///   // Return an authorization request effect
   /// ```
   public static func ~= <Value>(
-    keyPath: WritableKeyPath<Root, BindableState<Value>>,
+    keyPath: WritableKeyPath<Root, BindingState<Value>>,
     bindingAction: Self
   ) -> Bool {
     keyPath == bindingAction.keyPath
   }
 
   init<Value: Equatable>(
-    keyPath: WritableKeyPath<Root, BindableState<Value>>,
+    keyPath: WritableKeyPath<Root, BindingState<Value>>,
     set: @escaping (inout Root) -> Void,
     value: Value
   ) {
@@ -233,15 +233,15 @@ extension BindingAction {
   /// key path.
   ///
   /// Useful in transforming binding actions on view state into binding actions on reducer state
-  /// when the domain contains ``BindableState`` and ``BindableAction``.
+  /// when the domain contains ``BindingState`` and ``BindableAction``.
   ///
   /// For example, we can model an feature that can bind an integer count to a stepper and make a
   /// network request to fetch a fact about that integer with the following domain:
   ///
   /// ```swift
   /// struct MyFeature: ReducerProtocol {
   ///   struct State: Equatable {
-  ///     @BindableState var count = 0
+  ///     @BindingState var count = 0
   ///     var fact: String?
   ///     ...
   ///   }
@@ -279,7 +279,7 @@ extension BindingAction {
   /// ```swift
   /// extension MyFeatureView {
   ///   struct ViewState: Equatable {
-  ///     @BindableState var count: Int
+  ///     @BindingState var count: Int
   ///     let fact: String?
   ///     // no access to any other state on `MyFeature.State`, like child domains
   ///   }

Tests/ComposableArchitectureTests/BindingTests.swift

@@ -4,10 +4,10 @@ import XCTest
 @MainActor
 final class BindingTests: XCTestCase {
   #if swift(>=5.7)
-    func testNestedBindableState() {
+    func testNestedBindingState() {
       struct BindingTest: ReducerProtocol {
         struct State: Equatable {
-          @BindableState var nested = Nested()
+          @BindingState var nested = Nested()
 
           struct Nested: Equatable {
             var field = ""

Tests/ComposableArchitectureTests/DebugTests.swift

@@ -45,7 +45,7 @@
 
     func testBindingAction() {
       struct State {
-        @BindableState var width = 0
+        @BindingState var width = 0
       }
       let action = BindingAction.set(\State.$width, 50)
       var dump = ""
@@ -54,7 +54,7 @@
         dump,
         #"""
         BindingAction.set(
-          WritableKeyPath<State, BindableState<Int>>,
+          WritableKeyPath<State, BindingState<Int>>,
           50
         )
         """#

Tests/ComposableArchitectureTests/RuntimeWarningTests.swift

@@ -190,7 +190,7 @@
     @MainActor
     func testBindingUnhandledAction() {
       struct State: Equatable {
-        @BindableState var value = 0
+        @BindingState var value = 0
       }
       enum Action: BindableAction, Equatable {
         case binding(BindingAction<State>)