Adjust for SendableMetatype (#3266)

Lukasa · web-flow · commit c9e2ac115fd8 · 2025-06-13T09:12:25.000+01:00
Motivation

With the introduction of isolated conformances, it has become necessary
to start managing the use of metatypes for some of our protocols. In
general, we don't want to force the relevant protocols to only be
conformed in non-isolated forms. Instead, we just want to make the
specific APIs non-usable.

Modifications

- Add shims for SendableMetatype that only use it when it is available.
- Require SendableMetatype where needed, gated by @preconcurrency.

Result

We continue to be safe.
diff --git a/Benchmarks/Thresholds/nightly-next/NIOPosixBenchmarks.TCPEcho.p90.json b/Benchmarks/Thresholds/nightly-next/NIOPosixBenchmarks.TCPEcho.p90.json
@@ -1,3 +1,3 @@
 {
-  "mallocCountTotal" : 108
+  "mallocCountTotal": 108
 }
diff --git a/Benchmarks/Thresholds/nightly-next/NIOPosixBenchmarks.TCPEchoAsyncChannel.p90.json b/Benchmarks/Thresholds/nightly-next/NIOPosixBenchmarks.TCPEchoAsyncChannel.p90.json
@@ -1,3 +1,3 @@
 {
-  "mallocCountTotal" : 164376
-}
+  "mallocCountTotal": 82500
+}
diff --git a/IntegrationTests/tests_04_performance/Thresholds/nightly-main.json b/IntegrationTests/tests_04_performance/Thresholds/nightly-main.json
@@ -1,47 +1,47 @@
 {
-    "10000000_asyncsequenceproducer": 19,
-    "1000000_asyncwriter": 1000050,
-    "1000_addHandlers": 44050,
+    "1_reqs_1000_conn": 384050,
     "1000_addHandlers_sync": 37050,
+    "1000_addHandlers": 44050,
     "1000_addRemoveHandlers_handlercontext": 8050,
     "1000_addRemoveHandlers_handlername": 8050,
     "1000_addRemoveHandlers_handlertype": 8050,
-    "1000_autoReadGetAndSet": 18050,
     "1000_autoReadGetAndSet_sync": 0,
+    "1000_autoReadGetAndSet": 18050,
     "1000_copying_bytebufferview_to_array": 1050,
     "1000_copying_circularbuffer_to_array": 1050,
-    "1000_getHandlers": 8050,
     "1000_getHandlers_sync": 35,
+    "1000_getHandlers": 8050,
     "1000_reqs_1_conn": 26400,
     "1000_rst_connections": 145050,
     "1000_tcpbootstraps": 3050,
     "1000_tcpconnections": 152050,
     "1000_udp_reqs": 6050,
     "1000_udpbootstraps": 2050,
     "1000_udpconnections": 75050,
-    "1_reqs_1000_conn": 384050,
+    "1000000_asyncwriter": 1000050,
+    "10000000_asyncsequenceproducer": 20,
     "assume_isolated_scheduling_10000_executions": 89,
     "bytebuffer_lots_of_rw": 2050,
     "creating_10000_headers": 0,
     "decode_1000_ws_frames": 2050,
-    "encode_1000_ws_frames_holding_buffer": 3,
     "encode_1000_ws_frames_holding_buffer_with_mask": 2050,
-    "encode_1000_ws_frames_holding_buffer_with_space": 3,
     "encode_1000_ws_frames_holding_buffer_with_space_with_mask": 2050,
-    "encode_1000_ws_frames_new_buffer": 3050,
+    "encode_1000_ws_frames_holding_buffer_with_space": 3,
+    "encode_1000_ws_frames_holding_buffer": 3,
     "encode_1000_ws_frames_new_buffer_with_mask": 5050,
-    "encode_1000_ws_frames_new_buffer_with_space": 3050,
     "encode_1000_ws_frames_new_buffer_with_space_with_mask": 5050,
+    "encode_1000_ws_frames_new_buffer_with_space": 3050,
+    "encode_1000_ws_frames_new_buffer": 3050,
     "execute_hop_10000_tasks": 0,
     "flat_schedule_10000_tasks": 100100,
     "flat_schedule_assume_isolated_10000_tasks": 80100,
     "future_assume_isolated_lots_of_callbacks": 74050,
     "future_erase_result": 4050,
     "future_lots_of_callbacks": 74050,
-    "get_100000_headers_canonical_form": 500050,
-    "get_100000_headers_canonical_form_trimming_whitespace": 500050,
     "get_100000_headers_canonical_form_trimming_whitespace_from_long_string": 500050,
     "get_100000_headers_canonical_form_trimming_whitespace_from_short_string": 500050,
+    "get_100000_headers_canonical_form_trimming_whitespace": 500050,
+    "get_100000_headers_canonical_form": 500050,
     "modifying_1000_circular_buffer_elements": 0,
     "modifying_byte_buffer_view": 6050,
     "ping_pong_1000_reqs_1_conn": 314,
@@ -54,6 +54,6 @@
     "scheduling_10000_executions": 89,
     "submit_10000_tasks": 20100,
     "submit_assume_isolated_10000_tasks": 20100,
-    "udp_1000_reqs_1_conn": 6200,
-    "udp_1_reqs_1000_conn": 162050
+    "udp_1_reqs_1000_conn": 162050,
+    "udp_1000_reqs_1_conn": 6200
 }
diff --git a/IntegrationTests/tests_04_performance/Thresholds/nightly-next.json b/IntegrationTests/tests_04_performance/Thresholds/nightly-next.json
@@ -1,47 +1,47 @@
 {
-    "10000000_asyncsequenceproducer": 19,
-    "1000000_asyncwriter": 1000050,
-    "1000_addHandlers": 44050,
+    "1_reqs_1000_conn": 384000,
     "1000_addHandlers_sync": 37050,
+    "1000_addHandlers": 44050,
     "1000_addRemoveHandlers_handlercontext": 8050,
     "1000_addRemoveHandlers_handlername": 8050,
     "1000_addRemoveHandlers_handlertype": 8050,
-    "1000_autoReadGetAndSet": 18050,
     "1000_autoReadGetAndSet_sync": 0,
+    "1000_autoReadGetAndSet": 18050,
     "1000_copying_bytebufferview_to_array": 1050,
     "1000_copying_circularbuffer_to_array": 1050,
-    "1000_getHandlers": 8050,
     "1000_getHandlers_sync": 35,
+    "1000_getHandlers": 8050,
     "1000_reqs_1_conn": 26400,
     "1000_rst_connections": 145050,
     "1000_tcpbootstraps": 3050,
     "1000_tcpconnections": 152050,
     "1000_udp_reqs": 6050,
     "1000_udpbootstraps": 2050,
     "1000_udpconnections": 75050,
-    "1_reqs_1000_conn": 384050,
+    "1000000_asyncwriter": 1000050,
+    "10000000_asyncsequenceproducer": 20,
     "assume_isolated_scheduling_10000_executions": 89,
     "bytebuffer_lots_of_rw": 2050,
     "creating_10000_headers": 0,
     "decode_1000_ws_frames": 2050,
-    "encode_1000_ws_frames_holding_buffer": 3,
     "encode_1000_ws_frames_holding_buffer_with_mask": 2050,
-    "encode_1000_ws_frames_holding_buffer_with_space": 3,
     "encode_1000_ws_frames_holding_buffer_with_space_with_mask": 2050,
-    "encode_1000_ws_frames_new_buffer": 3050,
+    "encode_1000_ws_frames_holding_buffer_with_space": 3,
+    "encode_1000_ws_frames_holding_buffer": 3,
     "encode_1000_ws_frames_new_buffer_with_mask": 5050,
-    "encode_1000_ws_frames_new_buffer_with_space": 3050,
     "encode_1000_ws_frames_new_buffer_with_space_with_mask": 5050,
+    "encode_1000_ws_frames_new_buffer_with_space": 3050,
+    "encode_1000_ws_frames_new_buffer": 3050,
     "execute_hop_10000_tasks": 0,
     "flat_schedule_10000_tasks": 100100,
-    "flat_schedule_assume_isolated_10000_tasks": 90100,
+    "flat_schedule_assume_isolated_10000_tasks": 80100,
     "future_assume_isolated_lots_of_callbacks": 74050,
     "future_erase_result": 4050,
     "future_lots_of_callbacks": 74050,
-    "get_100000_headers_canonical_form": 700050,
-    "get_100000_headers_canonical_form_trimming_whitespace": 700050,
-    "get_100000_headers_canonical_form_trimming_whitespace_from_long_string": 700050,
-    "get_100000_headers_canonical_form_trimming_whitespace_from_short_string": 700050,
+    "get_100000_headers_canonical_form_trimming_whitespace_from_long_string": 500050,
+    "get_100000_headers_canonical_form_trimming_whitespace_from_short_string": 500050,
+    "get_100000_headers_canonical_form_trimming_whitespace": 500050,
+    "get_100000_headers_canonical_form": 500050,
     "modifying_1000_circular_buffer_elements": 0,
     "modifying_byte_buffer_view": 6050,
     "ping_pong_1000_reqs_1_conn": 314,
@@ -54,6 +54,6 @@
     "scheduling_10000_executions": 89,
     "submit_10000_tasks": 20100,
     "submit_assume_isolated_10000_tasks": 20100,
-    "udp_1000_reqs_1_conn": 6200,
-    "udp_1_reqs_1000_conn": 162050
-}
+    "udp_1_reqs_1000_conn": 162050,
+    "udp_1000_reqs_1_conn": 6200
+}
diff --git a/Sources/NIOCore/AsyncAwaitSupport.swift b/Sources/NIOCore/AsyncAwaitSupport.swift
@@ -280,7 +280,10 @@ extension ChannelPipeline {
             "ChannelHandlerContext is not Sendable and it is therefore not safe to be used outside of its EventLoop"
     )
     @inlinable
-    public func context<Handler: ChannelHandler>(handlerType: Handler.Type) async throws -> ChannelHandlerContext {
+    @preconcurrency
+    public func context<Handler: ChannelHandler & _NIOCoreSendableMetatype>(
+        handlerType: Handler.Type
+    ) async throws -> ChannelHandlerContext {
         try await self.context(handlerType: handlerType).map { UnsafeTransfer($0) }.get().wrappedValue
     }
 
diff --git a/Sources/NIOCore/ChannelPipeline.swift b/Sources/NIOCore/ChannelPipeline.swift
@@ -534,7 +534,10 @@ public final class ChannelPipeline: ChannelInvoker {
     ///   - handlerType: The type of the handler to search for.
     /// - Returns: the `EventLoopFuture` which will be notified once the the operation completes.
     @inlinable
-    public func context<Handler: ChannelHandler>(handlerType: Handler.Type) -> EventLoopFuture<ChannelHandlerContext> {
+    @preconcurrency
+    public func context<Handler: ChannelHandler & _NIOCoreSendableMetatype>(
+        handlerType: Handler.Type
+    ) -> EventLoopFuture<ChannelHandlerContext> {
         let promise = self.eventLoop.makePromise(of: ChannelHandlerContext.self)
 
         if self.eventLoop.inEventLoop {
@@ -555,7 +558,10 @@ public final class ChannelPipeline: ChannelInvoker {
     /// - Returns: An ``EventLoopFuture`` that is succeeded if a handler of the given type is contained in the pipeline. Otherwise
     /// the future will be failed with an error.
     @inlinable
-    public func containsHandler<Handler: ChannelHandler>(type: Handler.Type) -> EventLoopFuture<Void> {
+    @preconcurrency
+    public func containsHandler<Handler: ChannelHandler & _NIOCoreSendableMetatype>(
+        type: Handler.Type
+    ) -> EventLoopFuture<Void> {
         self.handler(type: type).map { _ in () }
     }
 
@@ -2424,7 +2430,10 @@ extension ChannelPipeline: CustomDebugStringConvertible {
     /// - Parameters:
     ///   - type: the type of `ChannelHandler` to return.
     @inlinable
-    public func handler<Handler: ChannelHandler>(type _: Handler.Type) -> EventLoopFuture<Handler> {
+    @preconcurrency
+    public func handler<Handler: ChannelHandler & _NIOCoreSendableMetatype>(
+        type _: Handler.Type
+    ) -> EventLoopFuture<Handler> {
         self.context(handlerType: Handler.self).map { context in
             guard let typedContext = context.handler as? Handler else {
                 preconditionFailure(
diff --git a/Sources/NIOCore/NIOCoreSendableMetatype.swift b/Sources/NIOCore/NIOCoreSendableMetatype.swift
@@ -0,0 +1,19 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2025 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+#if compiler(>=6.2)
+public typealias _NIOCoreSendableMetatype = SendableMetatype
+#else
+public typealias _NIOCoreSendableMetatype = Any
+#endif
diff --git a/Sources/NIOFileSystem/DirectoryEntries.swift b/Sources/NIOFileSystem/DirectoryEntries.swift
@@ -36,7 +36,8 @@ public struct DirectoryEntries: AsyncSequence, Sendable {
     /// Creates a ``DirectoryEntries`` sequence by wrapping an `AsyncSequence` of _batches_ of
     /// directory entries.
     @preconcurrency
-    public init<S: AsyncSequence & Sendable>(wrapping sequence: S) where S.Element == Batched.Element {
+    public init<S: AsyncSequence & Sendable>(wrapping sequence: S)
+    where S.Element == Batched.Element, S.AsyncIterator: _NIOFileSystemSendableMetatype {
         self.batchedSequence = Batched(wrapping: sequence)
     }
 
@@ -95,7 +96,8 @@ extension DirectoryEntries {
         /// Creates a ``DirectoryEntries/Batched`` sequence by wrapping an `AsyncSequence`
         /// of directory entry batches.
         @preconcurrency
-        public init<S: AsyncSequence & Sendable>(wrapping sequence: S) where S.Element == Element {
+        public init<S: AsyncSequence & Sendable>(wrapping sequence: S)
+        where S.Element == Element, S.AsyncIterator: _NIOFileSystemSendableMetatype {
             self.stream = BufferedOrAnyStream<[DirectoryEntry], DirectoryEntryProducer>(wrapping: sequence)
         }
 
diff --git a/Sources/NIOFileSystem/FileChunks.swift b/Sources/NIOFileSystem/FileChunks.swift
@@ -31,7 +31,9 @@ public struct FileChunks: AsyncSequence, Sendable {
     private let stream: BufferedOrAnyStream<ByteBuffer, FileChunkProducer>
 
     /// Create a ``FileChunks`` sequence backed by wrapping an `AsyncSequence`.
-    public init<S: AsyncSequence & Sendable>(wrapping sequence: S) where S.Element == ByteBuffer {
+    @preconcurrency
+    public init<S: AsyncSequence & Sendable>(wrapping sequence: S)
+    where S.Element == ByteBuffer, S.AsyncIterator: _NIOFileSystemSendableMetatype {
         self.stream = BufferedOrAnyStream(wrapping: sequence)
     }
 
diff --git a/Sources/NIOFileSystem/Internal/BufferedOrAnyStream.swift b/Sources/NIOFileSystem/Internal/BufferedOrAnyStream.swift
@@ -28,7 +28,8 @@ internal enum BufferedOrAnyStream<Element: Sendable, Delegate: NIOAsyncSequenceP
         self = .nioThrowingAsyncSequenceProducer(stream)
     }
 
-    internal init<S: AsyncSequence & Sendable>(wrapping stream: S) where S.Element == Element {
+    internal init<S: AsyncSequence & Sendable>(wrapping stream: S)
+    where S.Element == Element, S.AsyncIterator: _NIOFileSystemSendableMetatype {
         self = .anyAsyncSequence(AnyAsyncSequence(wrapping: stream))
     }
 
@@ -72,7 +73,8 @@ internal enum BufferedOrAnyStream<Element: Sendable, Delegate: NIOAsyncSequenceP
 internal struct AnyAsyncSequence<Element>: AsyncSequence, Sendable {
     private let _makeAsyncIterator: @Sendable () -> AsyncIterator
 
-    internal init<S: AsyncSequence & Sendable>(wrapping sequence: S) where S.Element == Element {
+    internal init<S: AsyncSequence & Sendable>(wrapping sequence: S)
+    where S.Element == Element, S.AsyncIterator: _NIOFileSystemSendableMetatype {
         self._makeAsyncIterator = {
             AsyncIterator(wrapping: sequence.makeAsyncIterator())
         }
@@ -82,7 +84,7 @@ internal struct AnyAsyncSequence<Element>: AsyncSequence, Sendable {
         self._makeAsyncIterator()
     }
 
-    internal struct AsyncIterator: AsyncIteratorProtocol {
+    internal struct AsyncIterator: AsyncIteratorProtocol, _NIOFileSystemSendableMetatype {
         private var iterator: any AsyncIteratorProtocol
 
         init<I: AsyncIteratorProtocol>(wrapping iterator: I) where I.Element == Element {
diff --git a/Sources/NIOFileSystem/NIOFileSystemSendableMetatype.swift b/Sources/NIOFileSystem/NIOFileSystemSendableMetatype.swift
@@ -0,0 +1,19 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2025 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+#if compiler(>=6.2)
+public typealias _NIOFileSystemSendableMetatype = SendableMetatype
+#else
+public typealias _NIOFileSystemSendableMetatype = Any
+#endif
diff --git a/Sources/NIOPosix/NIOPosixSendableMetatype.swift b/Sources/NIOPosix/NIOPosixSendableMetatype.swift
@@ -0,0 +1,19 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftNIO open source project
+//
+// Copyright (c) 2025 Apple Inc. and the SwiftNIO project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+#if compiler(>=6.2)
+public typealias _NIOPosixSendableMetatype = SendableMetatype
+#else
+public typealias _NIOPosixSendableMetatype = Any
+#endif
diff --git a/Sources/NIOPosix/SocketProtocols.swift b/Sources/NIOPosix/SocketProtocols.swift
@@ -13,7 +13,7 @@
 //===----------------------------------------------------------------------===//
 import NIOCore
 
-protocol BaseSocketProtocol: CustomStringConvertible {
+protocol BaseSocketProtocol: CustomStringConvertible, _NIOPosixSendableMetatype {
     associatedtype SelectableType: Selectable
 
     var isOpen: Bool { get }
diff --git a/Sources/NIOWebSocket/NIOWebSocketClientUpgrader.swift b/Sources/NIOWebSocket/NIOWebSocketClientUpgrader.swift
@@ -129,9 +129,6 @@ public final class NIOTypedWebSocketClientUpgrader<UpgradeResult: Sendable>: NIO
     }
 }
 
-@available(*, unavailable)
-extension NIOWebSocketClientUpgrader: Sendable {}
-
 extension NIOWebSocketClientUpgrader {
     /// Generates a random WebSocket Request Key by generating 16 bytes randomly and encoding them as a base64 string as defined in RFC6455 https://tools.ietf.org/html/rfc6455#section-4.1
     /// - Parameter generator: the `RandomNumberGenerator` used as a the source of randomness
diff --git a/Tests/NIOHTTP1Tests/HTTPServerUpgradeTests.swift b/Tests/NIOHTTP1Tests/HTTPServerUpgradeTests.swift
@@ -25,7 +25,7 @@ extension ChannelPipeline {
         try self.assertDoesNotContain(handlerType: HTTPServerUpgradeHandler.self)
     }
 
-    func assertDoesNotContain<Handler: ChannelHandler>(
+    func assertDoesNotContain<Handler: ChannelHandler & _NIOCoreSendableMetatype>(
         handlerType: Handler.Type,
         file: StaticString = #filePath,
         line: UInt = #line
@@ -49,7 +49,7 @@ extension ChannelPipeline {
         }
     }
 
-    func assertContains<Handler: ChannelHandler>(handlerType: Handler.Type) {
+    func assertContains<Handler: ChannelHandler & _NIOCoreSendableMetatype>(handlerType: Handler.Type) {
         XCTAssertNoThrow(try self.containsHandler(type: handlerType).wait(), "did not find handler")
     }
 

Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,3 @@`
`1`	`1`	`{`
`2`		`- "mallocCountTotal" : 108`
	`2`	`+ "mallocCountTotal": 108`
`3`	`3`	`}`
Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,3 @@`
`1`	`1`	`{`
`2`		`- "mallocCountTotal" : 164376`
`3`		`-}`
	`2`	`+ "mallocCountTotal": 82500`
	`3`	`+}`
Original file line number	Diff line number	Diff line change
`@@ -280,7 +280,10 @@ extension ChannelPipeline {`
`280`	`280`	`"ChannelHandlerContext is not Sendable and it is therefore not safe to be used outside of its EventLoop"`
`281`	`281`	`)`
`282`	`282`	`@inlinable`
`283`		`- public func context<Handler: ChannelHandler>(handlerType: Handler.Type) async throws -> ChannelHandlerContext {`
	`283`	`+ @preconcurrency`
	`284`	`+ public func context<Handler: ChannelHandler & _NIOCoreSendableMetatype>(`
	`285`	`+ handlerType: Handler.Type`
	`286`	`+ ) async throws -> ChannelHandlerContext {`
`284`	`287`	`try await self.context(handlerType: handlerType).map { UnsafeTransfer($0) }.get().wrappedValue`
`285`	`288`	`}`
`286`	`289`
Original file line number	Diff line number	Diff line change
`@@ -31,7 +31,9 @@ public struct FileChunks: AsyncSequence, Sendable {`
`31`	`31`	`private let stream: BufferedOrAnyStream<ByteBuffer, FileChunkProducer>`
`32`	`32`
`33`	`33`	/// Create a ``FileChunks`` sequence backed by wrapping an `AsyncSequence`.
`34`		`- public init<S: AsyncSequence & Sendable>(wrapping sequence: S) where S.Element == ByteBuffer {`
	`34`	`+ @preconcurrency`
	`35`	`+ public init<S: AsyncSequence & Sendable>(wrapping sequence: S)`
	`36`	`+ where S.Element == ByteBuffer, S.AsyncIterator: _NIOFileSystemSendableMetatype {`
`35`	`37`	`self.stream = BufferedOrAnyStream(wrapping: sequence)`
`36`	`38`	`}`
`37`	`39`
Original file line number	Diff line number	Diff line change
`@@ -28,7 +28,8 @@ internal enum BufferedOrAnyStream<Element: Sendable, Delegate: NIOAsyncSequenceP`
`28`	`28`	`self = .nioThrowingAsyncSequenceProducer(stream)`
`29`	`29`	`}`
`30`	`30`
`31`		`- internal init<S: AsyncSequence & Sendable>(wrapping stream: S) where S.Element == Element {`
	`31`	`+ internal init<S: AsyncSequence & Sendable>(wrapping stream: S)`
	`32`	`+ where S.Element == Element, S.AsyncIterator: _NIOFileSystemSendableMetatype {`
`32`	`33`	`self = .anyAsyncSequence(AnyAsyncSequence(wrapping: stream))`
`33`	`34`	`}`
`34`	`35`
`@@ -72,7 +73,8 @@ internal enum BufferedOrAnyStream<Element: Sendable, Delegate: NIOAsyncSequenceP`
`72`	`73`	`internal struct AnyAsyncSequence<Element>: AsyncSequence, Sendable {`
`73`	`74`	`private let _makeAsyncIterator: @Sendable () -> AsyncIterator`
`74`	`75`
`75`		`- internal init<S: AsyncSequence & Sendable>(wrapping sequence: S) where S.Element == Element {`
	`76`	`+ internal init<S: AsyncSequence & Sendable>(wrapping sequence: S)`
	`77`	`+ where S.Element == Element, S.AsyncIterator: _NIOFileSystemSendableMetatype {`
`76`	`78`	`self._makeAsyncIterator = {`
`77`	`79`	`AsyncIterator(wrapping: sequence.makeAsyncIterator())`
`78`	`80`	`}`
`@@ -82,7 +84,7 @@ internal struct AnyAsyncSequence<Element>: AsyncSequence, Sendable {`
`82`	`84`	`self._makeAsyncIterator()`
`83`	`85`	`}`
`84`	`86`
`85`		`- internal struct AsyncIterator: AsyncIteratorProtocol {`
	`87`	`+ internal struct AsyncIterator: AsyncIteratorProtocol, _NIOFileSystemSendableMetatype {`
`86`	`88`	`private var iterator: any AsyncIteratorProtocol`
`87`	`89`
`88`	`90`	`init<I: AsyncIteratorProtocol>(wrapping iterator: I) where I.Element == Element {`