Drop support for Swift <5.9 (#172)

Xcode 15 has been required for App Store submissions since April, so
let's simplify things.

.github/workflows/ci.yml

@@ -20,8 +20,7 @@ jobs:
  strategy:
  matrix:
  xcode:
- - '14.3.1'
- - '15.2'
+ - '15.4'
  steps:
  - uses: actions/checkout@v4
  - name: Select Xcode ${{ matrix.xcode }}
@@ -35,7 +34,7 @@ jobs:
  strategy:
  matrix:
  swift:
- - '5.9'
+ - '5.10'
  name: Ubuntu (Swift ${{ matrix.swift }})
  runs-on: ubuntu-latest
  container: swift:${{ matrix.swift }}

Package.swift

@@ -1,5 +1,6 @@
-// swift-tools-version: 5.6
+// swift-tools-version: 5.9
 
+import CompilerPluginSupport
 import PackageDescription
 
 let package = Package(
@@ -17,19 +18,36 @@ let package = Package(
  )
  ],
  dependencies: [
- .package(url: "https://github.com/pointfreeco/xctest-dynamic-overlay", from: "1.0.0")
+ .package(url: "https://github.com/apple/swift-syntax", "509.0.0"..<"601.0.0"),
+ .package(url: "https://github.com/pointfreeco/swift-macro-testing", from: "0.2.0"),
+ .package(url: "https://github.com/pointfreeco/xctest-dynamic-overlay", from: "1.0.0"),
  ],
  targets: [
  .target(
  name: "CasePaths",
  dependencies: [
- .product(name: "XCTestDynamicOverlay", package: "xctest-dynamic-overlay")
+ "CasePathsMacros",
+ .product(name: "XCTestDynamicOverlay", package: "xctest-dynamic-overlay"),
  ]
  ),
  .testTarget(
  name: "CasePathsTests",
  dependencies: ["CasePaths"]
  ),
+ .macro(
+ name: "CasePathsMacros",
+ dependencies: [
+ .product(name: "SwiftSyntaxMacros", package: "swift-syntax"),
+ .product(name: "SwiftCompilerPlugin", package: "swift-syntax"),
+ ]
+ ),
+ .testTarget(
+ name: "CasePathsMacrosTests",
+ dependencies: [
+ "CasePathsMacros",
+ .product(name: "MacroTesting", package: "swift-macro-testing"),
+ ]
+ ),
  ]
 )
 
@@ -39,3 +57,15 @@ let package = Package(
  .package(url: "https://github.com/apple/swift-docc-plugin", from: "1.0.0")
  )
 #endif
+
+for target in package.targets {
+ target.swiftSettings = target.swiftSettings ?? []
+ target.swiftSettings?.append(contentsOf: [
+ .enableExperimentalFeature("StrictConcurrency")
+ ])
+ // target.swiftSettings?.append(
+ // .unsafeFlags([
+ // "-enable-library-evolution",
+ // ])
+ // )
+}

Sources/CasePaths/AnyCasePath.swift

@@ -63,80 +63,44 @@ extension AnyCasePath: CustomDebugStringConvertible {
 #endif
 
 extension AnyCasePath {
- #if swift(>=5.9)
- @available(
- iOS, deprecated: 9999,
- message: "Use 'CasePathable.modify', or 'extract' and 'embed', instead."
- )
- @available(
- macOS, deprecated: 9999,
- message: "Use 'CasePathable.modify', or 'extract' and 'embed', instead."
- )
- @available(
- tvOS, deprecated: 9999,
- message: "Use 'CasePathable.modify', or 'extract' and 'embed', instead."
- )
- @available(
- watchOS, deprecated: 9999,
- message: "Use 'CasePathable.modify', or 'extract' and 'embed', instead."
- )
- public func modify<Result>(
- _ root: inout Root,
- _ body: (inout Value) throws -> Result
- ) throws -> Result {
- guard var value = self.extract(from: root) else { throw ExtractionFailed() }
- let result = try body(&value)
- root = self.embed(value)
- return result
- }
- #else
- /// Attempts to modify a value in a root.
- ///
- /// - Parameters:
- /// - root: A root to modify if the case path matches.
- /// - body: A closure that can mutate the case's associated value. If the closure throws, the
- /// root will be left unmodified.
- /// - Returns: The return value, if any, of the body closure.
- public func modify<Result>(
- _ root: inout Root,
- _ body: (inout Value) throws -> Result
- ) throws -> Result {
- guard var value = self.extract(from: root) else { throw ExtractionFailed() }
- let result = try body(&value)
- root = self.embed(value)
- return result
- }
- #endif
+ @available(
+ iOS, deprecated: 9999,
+ message: "Use 'CasePathable.modify', or 'extract' and 'embed', instead."
+ )
+ @available(
+ macOS, deprecated: 9999,
+ message: "Use 'CasePathable.modify', or 'extract' and 'embed', instead."
+ )
+ @available(
+ tvOS, deprecated: 9999,
+ message: "Use 'CasePathable.modify', or 'extract' and 'embed', instead."
+ )
+ @available(
+ watchOS, deprecated: 9999,
+ message: "Use 'CasePathable.modify', or 'extract' and 'embed', instead."
+ )
+ public func modify<Result>(
+ _ root: inout Root,
+ _ body: (inout Value) throws -> Result
+ ) throws -> Result {
+ guard var value = self.extract(from: root) else { throw ExtractionFailed() }
+ let result = try body(&value)
+ root = self.embed(value)
+ return result
+ }
 
- #if swift(>=5.9)
- @available(iOS, deprecated: 9999, message: "Chain case key paths together, instead.")
- @available(macOS, deprecated: 9999, message: "Chain case key paths together, instead.")
- @available(tvOS, deprecated: 9999, message: "Chain case key paths together, instead.")
- @available(watchOS, deprecated: 9999, message: "Chain case key paths together, instead.")
- public func appending<AppendedValue>(
- path: AnyCasePath<Value, AppendedValue>
- ) -> AnyCasePath<Root, AppendedValue> {
- AnyCasePath<Root, AppendedValue>(
- embed: { self.embed(path.embed($0)) },
- extract: { self.extract(from: $0).flatMap(path.extract) }
- )
- }
- #else
- /// Returns a new case path created by appending the given case path to this one.
- ///
- /// Use this method to extend this case path to the value type of another case path.
- ///
- /// - Parameter path: The case path to append.
- /// - Returns: A case path from the root of this case path to the value type of `path`.
- public func appending<AppendedValue>(
- path: AnyCasePath<Value, AppendedValue>
- ) -> AnyCasePath<Root, AppendedValue> {
- AnyCasePath<Root, AppendedValue>(
- embed: { self.embed(path.embed($0)) },
- extract: { self.extract(from: $0).flatMap(path.extract) }
- )
- }
- #endif
+ @available(iOS, deprecated: 9999, message: "Chain case key paths together, instead.")
+ @available(macOS, deprecated: 9999, message: "Chain case key paths together, instead.")
+ @available(tvOS, deprecated: 9999, message: "Chain case key paths together, instead.")
+ @available(watchOS, deprecated: 9999, message: "Chain case key paths together, instead.")
+ public func appending<AppendedValue>(
+ path: AnyCasePath<Value, AppendedValue>
+ ) -> AnyCasePath<Root, AppendedValue> {
+ AnyCasePath<Root, AppendedValue>(
+ embed: { self.embed(path.embed($0)) },
+ extract: { self.extract(from: $0).flatMap(path.extract) }
+ )
+ }
 }
 
 struct ExtractionFailed: Error {}

Sources/CasePaths/CasePathable.swift

@@ -43,22 +43,14 @@ public protocol CasePathable {
  static var allCasePaths: AllCasePaths { get }
 }
 
-#if swift(>=5.9)
- /// A type that is used to distinguish case key paths from key paths by wrapping the enum and
- /// associated value types.
- @_documentation(visibility:internal)
- @dynamicMemberLookup
- public struct Case<Value>: Sendable {
- fileprivate let _embed: @Sendable (Value) -> Any
- fileprivate let _extract: @Sendable (Any) -> Value?
- }
-#else
- @dynamicMemberLookup
- public struct Case<Value> {
- fileprivate let _embed: @Sendable (Value) -> Any
- fileprivate let _extract: @Sendable (Any) -> Value?
- }
-#endif
+/// A type that is used to distinguish case key paths from key paths by wrapping the enum and
+/// associated value types.
+@_documentation(visibility:internal)
+@dynamicMemberLookup
+public struct Case<Value>: Sendable {
+ fileprivate let _embed: @Sendable (Value) -> Any
+ fileprivate let _extract: @Sendable (Any) -> Value?
+}
 
 extension Case {
  public init<Root>(

Sources/CasePaths/EnumReflection.swift

@@ -222,12 +222,7 @@ private struct MetadataKind: Equatable {
  }
 
  @_spi(Reflection) public func tag<Enum>(of value: Enum) -> UInt32 {
- #if swift(<5.8)
- // NB: Workaround for https://github.com/apple/swift/issues/61708
- guard self.typeDescriptor.emptyCaseCount + self.typeDescriptor.payloadCaseCount > 1
- else { return 0 }
- #endif
- return withUnsafePointer(to: value) {
+ withUnsafePointer(to: value) {
  self.valueWitnessTable.getEnumTag($0, self.ptr)
  }
  }