Fix Swift 6.0 build

Author: FranzBusch

Sources/AsyncAlgorithms/MultiProducerSingleConsumerChannel/MultiProducerSingleConsumerChannel.swift

@@ -546,6 +546,15 @@ extension MultiProducerSingleConsumerChannel.ChannelAsyncSequence where Element:
         init(storage: MultiProducerSingleConsumerChannel._Storage) {
             self._backing = .init(storage: storage)
         }
+        
+        @inlinable
+        mutating func next() async throws -> Element? {
+            do {
+                return try await self._backing.storage.next(isolation: nil)
+            } catch {
+                throw error as! Failure
+            }
+        }
 
         @inlinable
         mutating func next(

Sources/Example/Example.swift

@@ -22,7 +22,7 @@ struct Example {
         count: Int,
         backpressureStrategy: MultiProducerSingleConsumerChannel<Int, Never>.Source.BackpressureStrategy
     ) async {
-        await withTaskGroup { group in
+        await withTaskGroup(of: Void.self) { group in
             let channelAndSource = MultiProducerSingleConsumerChannel.makeChannel(
                 of: Int.self,
                 backpressureStrategy: backpressureStrategy
@@ -47,7 +47,7 @@ struct Example {
     }
 
     static func testAsyncStream(count: Int) async {
-        await withTaskGroup { group in
+        await withTaskGroup(of: Void.self) { group in
             let (stream, continuation) = AsyncStream.makeStream(of: Int.self, bufferingPolicy: .unbounded)
 
             group.addTask {

Tests/AsyncAlgorithmsTests/MultiProducerSingleConsumerChannel/MultiProducerSingleConsumerChannelTests.swift

@@ -18,7 +18,7 @@ final class MultiProducerSingleConsumerChannelTests: XCTestCase {
 
     func testSourceDeinitialized_whenChanneling_andNoSuspendedConsumer() async throws {
         let manualExecutor = ManualTaskExecutor()
-        try await withThrowingTaskGroup { group in
+        try await withThrowingTaskGroup(of: Void.self) { group in
             let channelAndSource = MultiProducerSingleConsumerChannel.makeChannel(
                 of: Int.self,
                 backpressureStrategy: .watermark(low: 5, high: 10)
@@ -32,7 +32,7 @@ final class MultiProducerSingleConsumerChannelTests: XCTestCase {
             }
 
             group.addTask(executorPreference: manualExecutor) {
-                await channel.next()
+                _ = await channel.next()
             }
 
             withExtendedLifetime(source) {}
@@ -46,7 +46,7 @@ final class MultiProducerSingleConsumerChannelTests: XCTestCase {
 
     func testSourceDeinitialized_whenChanneling_andSuspendedConsumer() async throws {
         let manualExecutor = ManualTaskExecutor()
-        try await withThrowingTaskGroup { group in
+        try await withThrowingTaskGroup(of: Void.self) { group in
             let channelAndSource = MultiProducerSingleConsumerChannel.makeChannel(
                 of: Int.self,
                 backpressureStrategy: .watermark(low: 5, high: 10)
@@ -59,7 +59,7 @@ final class MultiProducerSingleConsumerChannelTests: XCTestCase {
             }
 
             group.addTask(executorPreference: manualExecutor) {
-                await channel.next()
+                _ = await channel.next()
             }
             manualExecutor.run()
             XCTAssertFalse(didTerminate)
@@ -204,7 +204,7 @@ final class MultiProducerSingleConsumerChannelTests: XCTestCase {
 
     func testSequenceDeinitialized_whenChanneling_andNoSuspendedConsumer() async throws {
         let manualExecutor = ManualTaskExecutor()
-        try await withThrowingTaskGroup { group in
+        try await withThrowingTaskGroup(of: Void.self) { group in
             let channelAndSource = MultiProducerSingleConsumerChannel.makeChannel(
                 of: Int.self,
                 backpressureStrategy: .watermark(low: 5, high: 10)
@@ -216,7 +216,7 @@ final class MultiProducerSingleConsumerChannelTests: XCTestCase {
             source.setOnTerminationCallback { didTerminate = true }
 
             group.addTask(executorPreference: manualExecutor) {
-                await asyncSequence.first { _ in true }
+                _ = await asyncSequence.first { _ in true }
             }
 
             withExtendedLifetime(source) {}
@@ -598,7 +598,7 @@ final class MultiProducerSingleConsumerChannelTests: XCTestCase {
     }
 
     func testWrite_whenConcurrentProduction() async throws {
-        await withThrowingTaskGroup { group in
+        await withThrowingTaskGroup(of: Void.self) { group in
             let channelAndSource = MultiProducerSingleConsumerChannel.makeChannel(
                 of: Int.self,
                 backpressureStrategy: .watermark(low: 2, high: 5)