apple · phausler · Jun 16, 2022 · Jun 15, 2022 · Jun 15, 2022 · Jun 15, 2022
diff --git a/Package.swift b/Package.swift
@@ -25,20 +25,10 @@ let package = Package(
     .systemLibrary(name: "_CAsyncSequenceValidationSupport"),
     .target(
       name: "AsyncAlgorithms_XCTest",
-      dependencies: ["AsyncAlgorithms", "AsyncSequenceValidation"],
-      swiftSettings: [
-        .unsafeFlags([
-          "-Xfrontend", "-disable-availability-checking"
-        ])
-      ]),
+      dependencies: ["AsyncAlgorithms", "AsyncSequenceValidation"]),
     .testTarget(
       name: "AsyncAlgorithmsTests",
-      dependencies: ["AsyncAlgorithms", "AsyncSequenceValidation", "AsyncAlgorithms_XCTest"],
-      swiftSettings: [
-        .unsafeFlags([
-          "-Xfrontend", "-disable-availability-checking"
-        ])
-      ]),
+      dependencies: ["AsyncAlgorithms", "AsyncSequenceValidation", "AsyncAlgorithms_XCTest"]),
   ]
 )
 

diff --git a/README.md b/README.md
@@ -87,28 +87,17 @@ Finally, add `import AsyncAlgorithms` to your source code.
 
 ## Getting Started
 
-⚠️ Please note that this package currently requires a recent [Swift Trunk Development toolchain](https://www.swift.org/download/#trunk-development-main). More information on how to use custom toolchains with Xcode can be viewed [here](https://developer.apple.com/library/archive/documentation/ToolsLanguages/Conceptual/Xcode_Overview/AlternativeToolchains.html).
+⚠️ Please note that this package requires Xcode 14 on macOS hosts. Previous versions of Xcode do not contain the required Swift version.
 
 ### Building/Testing Using Xcode on macOS
 
-  1. Download the most recent development Xcode toolchain.
-  2. Install the package
-  4. Select the development toolchain in Xcode
-  4. Open the `swift-async-algorithms` package directory in Xcode
-  5. Build or Test in Xcode as normal
-
-⚠️ Note: `swift test` does not currently work properly with custom toolchains for this package.
+  1. In the `swift-async-algorithms` directory run `swift build` or `swift test` accordingly
 
 ### Building/Testing on Linux
 
   1. Download the most recent development toolchain for your Linux distribution
   2. Decompress the archive to a path in which the `swift` executable is in the binary search path environment variable (`$PATH`)
   3. In the `swift-async-algorithms` directory run `swift build` or `swift test` accordingly
-
-### Building with Swift 5.6
-
-  1. `git checkout swift-5.6`
-  2. run `swift build` or `swift test` accordingly
 
 ## Source Stability
 

diff --git a/Sources/AsyncSequenceValidation/AsyncSequenceValidationDiagram.swift b/Sources/AsyncSequenceValidation/AsyncSequenceValidationDiagram.swift
@@ -11,7 +11,6 @@
 
 import _CAsyncSequenceValidationSupport
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 @resultBuilder
 public struct AsyncSequenceValidationDiagram : Sendable {
   public struct Component<T> {
@@ -97,15 +96,20 @@ public struct AsyncSequenceValidationDiagram : Sendable {
   }
 
   let queue: WorkQueue
+  let _clock: Clock
 
   public var inputs: InputList
-  public let clock: Clock
+
+  @available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
+  public var clock: Clock {
+    _clock
+  }
 
   internal init() {
     let queue = WorkQueue()
     self.queue = queue
     self.inputs = InputList(queue: queue)
-    self.clock = Clock(queue: queue)
+    self._clock = Clock(queue: queue)
   }
 }
 
diff --git a/Sources/AsyncSequenceValidation/Clock.swift b/Sources/AsyncSequenceValidation/Clock.swift
@@ -11,7 +11,6 @@
 
 import AsyncAlgorithms
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 extension AsyncSequenceValidationDiagram {
   public struct Clock {
     let queue: WorkQueue
@@ -22,8 +21,20 @@ extension AsyncSequenceValidationDiagram {
   }
 }
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
-extension AsyncSequenceValidationDiagram.Clock: Clock {
+
+public protocol TestClock: Sendable {
+  associatedtype Instant: TestInstant
+
+  var now: Instant { get }
+
+  func sleep(until deadline: Self.Instant, tolerance: Self.Instant.Duration?) async throws
+}
+
+public protocol TestInstant: Equatable {
+  associatedtype Duration
+}
+
+extension AsyncSequenceValidationDiagram.Clock {
   public struct Step: DurationProtocol, Hashable, CustomStringConvertible {
     internal var rawValue: Int
 
@@ -66,7 +77,7 @@ extension AsyncSequenceValidationDiagram.Clock: Clock {
     }
   }
 
-  public struct Instant: InstantProtocol, CustomStringConvertible {
+  public struct Instant: CustomStringConvertible {
     public typealias Duration = Step
 
     let when: Step
@@ -111,3 +122,13 @@ extension AsyncSequenceValidationDiagram.Clock: Clock {
     }
   }
 }
+
+extension AsyncSequenceValidationDiagram.Clock.Instant: TestInstant { }
+
+@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
+extension AsyncSequenceValidationDiagram.Clock.Instant: InstantProtocol { }
+
+extension AsyncSequenceValidationDiagram.Clock: TestClock { }
+
+@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
+extension AsyncSequenceValidationDiagram.Clock: Clock { }
diff --git a/Sources/AsyncSequenceValidation/Event.swift b/Sources/AsyncSequenceValidation/Event.swift
@@ -9,7 +9,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 extension AsyncSequenceValidationDiagram {
   struct Failure: Error, Equatable { }
 

diff --git a/Sources/AsyncSequenceValidation/Expectation.swift b/Sources/AsyncSequenceValidation/Expectation.swift
@@ -9,7 +9,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 extension AsyncSequenceValidationDiagram {
   public struct ExpectationResult: Sendable {
     public struct Event: Sendable {

diff --git a/Sources/AsyncSequenceValidation/Input.swift b/Sources/AsyncSequenceValidation/Input.swift
@@ -9,7 +9,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 extension AsyncSequenceValidationDiagram {
   public struct Specification: Sendable {
     public let specification: String

diff --git a/Sources/AsyncSequenceValidation/Job.swift b/Sources/AsyncSequenceValidation/Job.swift
@@ -11,7 +11,6 @@
 
 import _CAsyncSequenceValidationSupport
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 struct Job: Hashable, @unchecked Sendable {
   let job: JobRef
 

diff --git a/Sources/AsyncSequenceValidation/TaskDriver.swift b/Sources/AsyncSequenceValidation/TaskDriver.swift
@@ -20,7 +20,6 @@ import _CAsyncSequenceValidationSupport
 #endif
 
 #if canImport(Darwin)
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 func start_thread(_ raw: UnsafeMutableRawPointer) -> UnsafeMutableRawPointer? {
   Unmanaged<TaskDriver>.fromOpaque(raw).takeRetainedValue().run()
   return nil
@@ -34,7 +33,6 @@ func start_thread(_ raw: UnsafeMutableRawPointer?) -> UnsafeMutableRawPointer? {
 #error("TODO: Port TaskDriver threading to windows")
 #endif
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 final class TaskDriver {
   let work: (TaskDriver) -> Void
   let queue: WorkQueue

diff --git a/Sources/AsyncSequenceValidation/Test.swift b/Sources/AsyncSequenceValidation/Test.swift
@@ -19,22 +19,20 @@ internal func _swiftJobRun(
   _ executor: UnownedSerialExecutor
 ) -> ()
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 public protocol AsyncSequenceValidationTest: Sendable {
   var inputs: [AsyncSequenceValidationDiagram.Specification] { get }
   var output: AsyncSequenceValidationDiagram.Specification { get }
 
-  func test<C: Clock>(with clock: C, activeTicks: [C.Instant], output: AsyncSequenceValidationDiagram.Specification, _ event: (String) -> Void) async throws
+  func test<C: TestClock>(with clock: C, activeTicks: [C.Instant], output: AsyncSequenceValidationDiagram.Specification, _ event: (String) -> Void) async throws
 }
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 extension AsyncSequenceValidationDiagram {
   struct Test<Operation: AsyncSequence>: AsyncSequenceValidationTest, @unchecked Sendable where Operation.Element == String {
     let inputs: [Specification]
     let sequence: Operation
     let output: Specification
 
-    func test<C: _Concurrency.Clock>(with clock: C, activeTicks: [C.Instant], output: Specification, _ event: (String) -> Void) async throws {
+    func test<C: TestClock>(with clock: C, activeTicks: [C.Instant], output: Specification, _ event: (String) -> Void) async throws {
       var iterator = sequence.makeAsyncIterator()
       do {
         for tick in activeTicks {
@@ -265,7 +263,7 @@ extension AsyncSequenceValidationDiagram {
     @AsyncSequenceValidationDiagram _ build: (AsyncSequenceValidationDiagram) -> Test
   ) throws -> (ExpectationResult, [ExpectationFailure]) {
     let diagram = AsyncSequenceValidationDiagram()
-    let clock = diagram.clock
+    let clock = diagram._clock
     let test = build(diagram)
     for index in 0..<test.inputs.count {
       // fault in all inputs

diff --git a/Sources/AsyncSequenceValidation/Theme.swift b/Sources/AsyncSequenceValidation/Theme.swift
@@ -9,21 +9,18 @@
 //
 //===----------------------------------------------------------------------===//
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 public protocol AsyncSequenceValidationTheme {
   func token(_ character: Character, inValue: Bool) -> AsyncSequenceValidationDiagram.Token
 
   func description(for token: AsyncSequenceValidationDiagram.Token) -> String
 }
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 extension AsyncSequenceValidationTheme where Self == AsyncSequenceValidationDiagram.ASCIITheme {
   public static var ascii: AsyncSequenceValidationDiagram.ASCIITheme {
     return AsyncSequenceValidationDiagram.ASCIITheme()
   }
 }
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 extension AsyncSequenceValidationDiagram {
   public enum Token: Sendable {
     case step

diff --git a/Sources/AsyncSequenceValidation/WorkQueue.swift b/Sources/AsyncSequenceValidation/WorkQueue.swift
@@ -9,7 +9,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
 struct WorkQueue: Sendable {
   enum Item: CustomStringConvertible, Comparable {
     case blocked(Token, AsyncSequenceValidationDiagram.Clock.Instant, UnsafeContinuation<Void, Error>)

diff --git a/Tests/AsyncAlgorithmsTests/TestChunk.swift b/Tests/AsyncAlgorithmsTests/TestChunk.swift
@@ -22,7 +22,6 @@ func concatCharacters(_ array: [String]) -> String {
 }
 
 final class TestChunk: XCTestCase {
-
   func test_signal_equalChunks() {
     validate {
       "ABC-    DEF-    GHI-     |"
@@ -113,79 +112,89 @@ final class TestChunk: XCTestCase {
     }
   }
 
-  func test_time_equalChunks() {
+  func test_time_equalChunks() throws {
+    guard #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) else { throw XCTSkip("Skipped due to Clock/Instant/Duration availability") }
     validate {
       "ABC-    DEF-    GHI-     |"
       $0.inputs[0].chunked(by: .repeating(every: .steps(4), clock: $0.clock)).map(concatCharacters)
       "---'ABC'---'DEF'---'GHI'|"
     }
   }
 
-  func test_time_unequalChunks() {
+  func test_time_unequalChunks() throws {
+    guard #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) else { throw XCTSkip("Skipped due to Clock/Instant/Duration availability") }
     validate {
       "AB------    A------- ABCDEFG-         |"
       $0.inputs[0].chunked(by: .repeating(every: .steps(8), clock: $0.clock)).map(concatCharacters)
       "-------'AB' -------A -------'ABCDEFG'|"
     }
   }
 
-  func test_time_emptyChunks() {
+  func test_time_emptyChunks() throws {
+    guard #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) else { throw XCTSkip("Skipped due to Clock/Instant/Duration availability") }
     validate {
       "-- 1- --|"
       $0.inputs[0].chunked(by: .repeating(every: .steps(2), clock: $0.clock)).map(concatCharacters)
       "-- -1 --|"
     }
   }
 
-  func test_time_error() {
+  func test_time_error() throws {
+    guard #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) else { throw XCTSkip("Skipped due to Clock/Instant/Duration availability") }
     validate {
       "AB^"
       $0.inputs[0].chunked(by: .repeating(every: .steps(5), clock: $0.clock)).map(concatCharacters)
       "--^"
     }
   }
 
-  func test_time_unsignaledTrailingChunk() {
+  func test_time_unsignaledTrailingChunk() throws {
+    guard #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) else { throw XCTSkip("Skipped due to Clock/Instant/Duration availability") }
     validate {
       "111-111|"
       $0.inputs[0].chunked(by: .repeating(every: .steps(4), clock: $0.clock)).map(sumCharacters)
       "---3---[3|]"
     }
   }
 
-  func test_timeAndCount_timeAlwaysPrevails() {
+  func test_timeAndCount_timeAlwaysPrevails() throws {
+    guard #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) else { throw XCTSkip("Skipped due to Clock/Instant/Duration availability") }
     validate {
       "AB------    A------- ABCDEFG-         |"
       $0.inputs[0].chunks(ofCount: 42, or: .repeating(every: .steps(8), clock: $0.clock)).map(concatCharacters)
       "-------'AB' -------A -------'ABCDEFG'|"
     }
   }
 
-  func test_timeAndCount_countAlwaysPrevails() {
+  func test_timeAndCount_countAlwaysPrevails() throws {
+    guard #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) else { throw XCTSkip("Skipped due to Clock/Instant/Duration availability") }
     validate {
       "AB   --A-B   -|"
       $0.inputs[0].chunks(ofCount: 2, or: .repeating(every: .steps(8), clock: $0.clock)).map(concatCharacters)
       "-'AB'----'AB'-|"
     }
   }
 
-  func test_timeAndCount_countResetsAfterCount() {
+  func test_timeAndCount_countResetsAfterCount() throws {
+    guard #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) else { throw XCTSkip("Skipped due to Clock/Instant/Duration availability") }
     validate {
       "ABCDE      --- ABCDE      |"
       $0.inputs[0].chunks(ofCount: 5, or: .repeating(every: .steps(8), clock: $0.clock)).map(concatCharacters)
       "----'ABCDE'--- ----'ABCDE'|"
     }
   }
 
-  func test_timeAndCount_countResetsAfterSignal() {
+  func test_timeAndCount_countResetsAfterSignal() throws {
+    guard #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) else { throw XCTSkip("Skipped due to Clock/Instant/Duration availability") }
     validate {
       "AB------    ABCDE      |"
       $0.inputs[0].chunks(ofCount: 5, or: .repeating(every: .steps(8), clock: $0.clock)).map(concatCharacters)
       "-------'AB' ----'ABCDE'|"
     }
   }
 
-  func test_timeAndCount_error() {
+  func test_timeAndCount_error() throws {
+    guard #available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *) else { throw XCTSkip("Skipped due to Clock/Instant/Duration availability") }
     validate {
       "ABC^"
       $0.inputs[0].chunks(ofCount: 5, or: .repeating(every: .steps(8), clock: $0.clock)).map(concatCharacters)