Remove platform requirements (#4)

### Motivation

The 26.0 platform requirements are only present due to the
`swift-nio-quic` dependency. Moreover, this dependency is only required
by the `H3IntegrationTests` test target.

Following from apple/swift-nio-quic#18, we can
now transitively drop the platform requirements in this repo and gate
declarations using `swift-nio-quic` APIs in `H3IntegrationTests` behind
an `@available(anyAppleOS 26, *)` guard.

### Modifications

- Updated the `swift-nio-quic` dependency to point to the branch of
apple/swift-nio-quic#18.
- Removed the `platform` declaration in `Package.swift`.
- Added an `@available(anyAppleOS 26, *)` guard to all declarations in
`H3IntegrationTests` using `swift-nio-quic` APIs.
- Added an `@available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0,
*)` guard to all declarations behind the `HTTP3AsyncInterface` SPI (to
match the availability of `AsyncStreaming`).


### Result

`swift-nio-http3` can be used without 26.0 platform requirements.

---------

Co-authored-by: George Barnett <gbarnett@apple.com>

Author: aryan-25

Package.swift

@@ -18,11 +18,11 @@ import PackageDescription
 var swiftSettings: [PackageDescription.SwiftSetting] = [
     .enableUpcomingFeature("ExistentialAny"),
     .enableUpcomingFeature("InternalImportsByDefault"),
+    .enableExperimentalFeature("AnyAppleOSAvailability"),
 ]
 
 let package = Package(
     name: "swift-nio-http3",
-    platforms: [.macOS("26.0"), .iOS("26.0"), .tvOS("26.0"), .watchOS("26.0"), .visionOS("26.0")],
     products: [
         .library(name: "NIOHTTP3", targets: ["NIOHTTP3"])
     ],

Sources/NIOHTTP3/HTTP3ConnectionHandler.swift

@@ -185,6 +185,7 @@ public final class HTTP3ConnectionHandler<StreamCreator: QUICStreamCreator & Sen
     ///   - connection: An instance of ``HTTP3ServerConnection`` which inbound connections can be vended to.
     /// - Returns: A ``HTTP3ConnectionHandler``.
     @_spi(HTTP3AsyncInterface)
+    @available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0, *)
     public static func server<Output: Sendable>(
         eventLoop: any EventLoop,
         configuration: HTTP3ServerConfiguration,

Sources/NIOHTTP3/HTTP3ConnectionMultiplexer.swift

@@ -21,6 +21,7 @@ public import NIOQUICHelpers
 // Allow creating outbound push streams.
 /// A HTTP/3 connection from a servers side. Allows iterating inbound streams.
 @_spi(HTTP3AsyncInterface)
+@available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0, *)
 public struct HTTP3ServerConnection<Output: Sendable, StreamCreator: QUICStreamCreator>: Sendable {
     /// Channel initializer called for each new inbound stream.
     private let inboundStreamInitializer: @Sendable (HTTP3StreamInitializerParameters) -> EventLoopFuture<Output>
@@ -85,6 +86,7 @@ extension HTTP3ServerConnection.InboundStreams.AsyncIterator: Sendable {}
 // Allow iterating incoming push streams.
 /// A HTTP/3 connection from a clients side. Allows creating outbound request streams.
 @_spi(HTTP3AsyncInterface)
+@available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0, *)
 public struct HTTP3ClientConnection<
     Output: Sendable,
     StreamCreator: QUICStreamCreator & SendableMetatype
@@ -144,6 +146,7 @@ package protocol StreamMultiplexerContinuation: Sendable {
     func finish()
 }
 
+@available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0, *)
 extension HTTP3ServerConnection: StreamMultiplexerContinuation {
     package func initialize(parameters: HTTP3StreamInitializerParameters) -> EventLoopFuture<any Sendable> {
         self.inboundStreamInitializer(parameters).map { $0 as any Sendable }
@@ -163,6 +166,7 @@ extension HTTP3ServerConnection: StreamMultiplexerContinuation {
 /// You can use this type to wrap a QUIC implementation. Have the QUIC implementation call ``yield(connection:)`` and ``finish()`` as appropriate.
 /// Then, you can easily iterate through incoming connections and handle them.
 @_spi(HTTP3AsyncInterface)
+@available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0, *)
 public struct HTTP3ServerConnectionMultiplexer<Output: Sendable, StreamCreator: QUICStreamCreator>: Sendable {
     /// The inboundConnections' continuation.
     private let inboundConnectionsContinuation: AsyncStream<HTTP3ServerConnection<Output, StreamCreator>>.Continuation
@@ -219,6 +223,7 @@ extension HTTP3ServerConnectionMultiplexer.InboundConnections.AsyncIterator: Sen
 
 /// Implementations of QUIC should implement this protocol to be able to use the HTTP3ClientConnectionMultiplexer.
 @_spi(HTTP3AsyncInterface)
+@available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0, *)
 public protocol HTTP3ConnectionCreator {
     /// Create a new QUIC connection using the parameters provided.
     /// - Parameters:
@@ -235,6 +240,7 @@ public protocol HTTP3ConnectionCreator {
 
 /// Allows you to create outbound connections as a client.
 @_spi(HTTP3AsyncInterface)
+@available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0, *)
 public struct HTTP3ClientConnectionMultiplexer<
     ConnectionCreator: HTTP3ConnectionCreator & SendableMetatype,
     StreamCreator: QUICStreamCreator

Tests/H3IntegrationTests/AsyncEndToEndTests.swift

@@ -28,30 +28,16 @@ import struct NIOQUIC.QUICStreamCreator
 struct AsyncEndToEndTests {
     private let eventLoopGroup = MultiThreadedEventLoopGroup.singleton
 
-    private static func supportsAsyncInterface() -> Bool {
-        if #available(macOS 10.15, iOS 13.0, tvOS 13.0, watchOS 6.0, visionOS 1.0, macCatalyst 13.0, *) {
-            return true
-        } else {
-            return false
-        }
-    }
-
     private static let standardAuthenticationConfigurations: [AuthenticationConfiguration] = {
         [.keys, .certs]
     }()
 
-    @Test(
-        .enabled(if: Self.supportsAsyncInterface()),
-        arguments: Self.standardAuthenticationConfigurations
-    )
+    @Test(arguments: Self.standardAuthenticationConfigurations)
+    @available(anyAppleOS 26, *)
     func asyncRoundtrip(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let serverLogger = Logger(label: "Server")
         let clientLogger = Logger(label: "Client")
 
-        guard #available(macOS 10.15, iOS 13.0, tvOS 13.0, watchOS 6.0, visionOS 1.0, macCatalyst 13.0, *) else {
-            fatalError("Test shouldn't be enabled on this platform")
-        }
-
         let credentials = try TestCertificates.makeCredentials(for: authenticationConfiguration)
         let serverName: String
         switch credentials {
@@ -138,16 +124,13 @@ struct AsyncEndToEndTests {
         }
     }
 
-    @Test(.enabled(if: Self.supportsAsyncInterface()), arguments: Self.standardAuthenticationConfigurations)
+    @Test(arguments: Self.standardAuthenticationConfigurations)
+    @available(anyAppleOS 26, *)
     func goawayMidRequestWithHighID(authenticationConfiguration: AuthenticationConfiguration) async throws {
         // Send a goaway to the client in the middle of a request. See that the client can not make further requests.
         let serverLogger = Logger(label: "Server")
         let clientLogger = Logger(label: "Client")
 
-        guard #available(macOS 10.15, iOS 13.0, tvOS 13.0, watchOS 6.0, visionOS 1.0, macCatalyst 13.0, *) else {
-            fatalError("Test shouldn't be enabled on this platform")
-        }
-
         let credentials = try TestCertificates.makeCredentials(for: authenticationConfiguration)
         let serverName: String
         switch credentials {
@@ -245,17 +228,14 @@ struct AsyncEndToEndTests {
         try await clientChannel.close()
     }
 
-    @Test(.enabled(if: Self.supportsAsyncInterface()), arguments: Self.standardAuthenticationConfigurations)
+    @Test(arguments: Self.standardAuthenticationConfigurations)
+    @available(anyAppleOS 26, *)
     func goawayMidRequest(authenticationConfiguration: AuthenticationConfiguration) async throws {
         // Send a goaway to a client during a request, such that the goaway affects the request in flight.
         // See that the server rejects the request.
         let serverLogger = Logger(label: "Server")
         let clientLogger = Logger(label: "Client")
 
-        guard #available(macOS 10.15, iOS 13.0, tvOS 13.0, watchOS 6.0, visionOS 1.0, macCatalyst 13.0, *) else {
-            fatalError("Test shouldn't be enabled on this platform")
-        }
-
         let credentials = try TestCertificates.makeCredentials(for: authenticationConfiguration)
         let serverName: String
         switch credentials {
@@ -385,6 +365,7 @@ struct AsyncEndToEndTests {
 
     // MARK: - Helper Functions
 
+    @available(anyAppleOS 26, *)
     private func makeHTTP3Server(
         credentials: Credentials,
         settings: HTTP3Settings,
@@ -473,6 +454,7 @@ struct AsyncEndToEndTests {
         }
     }
 
+    @available(anyAppleOS 26, *)
     private func makeHTTP3Client(
         credentials: Credentials,
         settings: HTTP3Settings,

Tests/H3IntegrationTests/EndToEndTests.swift

@@ -218,6 +218,7 @@ struct EndToEndTests {
     }()
 
     @Test(arguments: Self.standardAuthenticationConfigurations)
+    @available(anyAppleOS 26, *)
     func testSettingsFrame(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -304,6 +305,7 @@ struct EndToEndTests {
         .disabled("See DynamicTable document in NIOHTTP3 module"),
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testRoundtripWithSlowDynamicTable(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -524,6 +526,7 @@ struct EndToEndTests {
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testRoundtripWithoutDynamicTable(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -629,6 +632,7 @@ struct EndToEndTests {
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testConnectionError(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -685,6 +689,7 @@ struct EndToEndTests {
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testServerClosesConnection(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -732,6 +737,7 @@ struct EndToEndTests {
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testClosingConnectionAlsoClosesStreams(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -786,6 +792,7 @@ struct EndToEndTests {
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testServerClosesConnectionWithActiveStream(
         authenticationConfiguration: AuthenticationConfiguration
     ) async throws {
@@ -853,6 +860,7 @@ struct EndToEndTests {
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testStreamError(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -924,6 +932,7 @@ struct EndToEndTests {
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testUnknownIncomingStream(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -977,10 +986,11 @@ struct EndToEndTests {
         try await serverChannel.close()
     }
 
+    // This is always an error; clients must not open push streams to servers.
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
-    // This is always an error; clients must not open push streams to servers.
+    @available(anyAppleOS 26, *)
     func testIncomingPushStreamOnServer(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -1034,10 +1044,11 @@ struct EndToEndTests {
         try await serverChannel.close()
     }
 
+    // This is an error because the client hasn't specified that it wants to receive push (by sending a MAX_PUSH_ID frame)
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
-    // This is an error because the client hasn't specified that it wants to receive push (by sending a MAX_PUSH_ID frame)
+    @available(anyAppleOS 26, *)
     func testIncomingPushStreamOnClient(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -1124,6 +1135,7 @@ struct EndToEndTests {
         .disabled("See DynamicTable document in NIOHTTP3 module"),
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testBadQPACKInstruction(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -1192,10 +1204,11 @@ struct EndToEndTests {
         try await serverChannel.close()
     }
 
+    // If the connection handler gets a shouldquiesce event then the stream handlers should also
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
-    // If the connection handler gets a shouldquiesce event then the stream handlers should also
+    @available(anyAppleOS 26, *)
     func testForwardShouldQuiesce(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -1254,6 +1267,7 @@ struct EndToEndTests {
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testNoOutboundRequestsAfterGoawayReceived(
         authenticationConfiguration: AuthenticationConfiguration
     ) async throws {
@@ -1377,6 +1391,7 @@ struct EndToEndTests {
     @Test(
         arguments: Self.standardAuthenticationConfigurations
     )
+    @available(anyAppleOS 26, *)
     func testControlStreamClosed(authenticationConfiguration: AuthenticationConfiguration) async throws {
         let host = "127.0.0.1"
 
@@ -1461,6 +1476,7 @@ struct EndToEndTests {
 
     // MARK: - Helper Functions
 
+    @available(anyAppleOS 26, *)
     private func makeServer(
         credentials: Credentials,
         host: String,
@@ -1491,6 +1507,7 @@ struct EndToEndTests {
         )
     }
 
+    @available(anyAppleOS 26, *)
     private func makeClient(
         credentials: Credentials,
         host: String,
@@ -1515,6 +1532,7 @@ struct EndToEndTests {
         )
     }
 
+    @available(anyAppleOS 26, *)
     private static func createHTTP3ClientChannel(
         eventLoopGroup: any EventLoopGroup,
         host: String,
@@ -1563,6 +1581,7 @@ struct EndToEndTests {
         return try await httpChannelFuture.get()
     }
 
+    @available(anyAppleOS 26, *)
     private static func createHTTP3ServerChannel(
         eventLoopGroup: any EventLoopGroup,
         host: String,

Tests/H3IntegrationTests/HTTP3+NIOQUIC.swift

@@ -28,6 +28,7 @@ import struct NIOQUIC.QUICStreamCreator
 typealias QUICHTTP3ConnectionHandler = HTTP3ConnectionHandler<QUICStreamCreator>
 
 // MARK: Configure with async interface
+@available(anyAppleOS 26, *)
 extension ChannelPipeline.SynchronousOperations {
     /// Setup a HTTP/3 server pipeline on a UDP channel.
     ///
@@ -201,6 +202,7 @@ extension ChannelPipeline.SynchronousOperations {
 
 // MARK: Configure without async interface
 
+@available(anyAppleOS 26, *)
 extension ChannelPipeline.SynchronousOperations {
     /// Setup a HTTP/3 server pipeline on a UDP channel.
     ///

Tests/H3IntegrationTests/QUICConfiguration.swift

@@ -16,6 +16,7 @@ import class Foundation.FileManager
 import struct Foundation.UUID
 import struct NIOQUIC.QUICConfiguration
 
+@available(anyAppleOS 26, *)
 extension QUICConfiguration {
     static func makeH3ServerConfig(
         serverName: String,

Tests/H3IntegrationTests/QUICConnectionCreator.swift

@@ -20,6 +20,7 @@ import NIOQUICHelpers
 
 typealias ConcreteQUICStreamCreator = NIOQUIC.QUICStreamCreator
 
+@available(anyAppleOS 26, *)
 struct QUICConnectionCreator: HTTP3ConnectionCreator {
     let quicHandler: QUICHandler
     let connectionInitializer: @Sendable (any Channel, ConcreteQUICStreamCreator) -> EventLoopFuture<any Channel>