feat: migrate to Swift 6.0 with Sendable/consuming annotations

CLAUDE.md

@@ -41,12 +41,12 @@ The library is structured as a single module with organized subdirectories:
 
 ## Platform Support
 
-- iOS 13.0+
-- macOS 10.15+
-- macCatalyst 13.0+
-- watchOS 6.0+
-- tvOS 13.0+
-- Swift 5.10+
+- iOS 16.0+
+- macOS 13.0+
+- macCatalyst 16.0+
+- watchOS 9.0+
+- tvOS 16.0+
+- Swift 6.0+
 
 ## Development Commands
 

Package.swift

@@ -1,16 +1,16 @@
-// swift-tools-version: 5.10
+// swift-tools-version: 6.0
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
 import PackageDescription
 
 let package = Package(
   name: "swift-http-client",
   platforms: [
-    .iOS(.v13),
-    .macCatalyst(.v13),
-    .macOS(.v10_15),
-    .watchOS(.v6),
-    .tvOS(.v13),
+    .iOS(.v16),
+    .macCatalyst(.v16),
+    .macOS(.v13),
+    .watchOS(.v9),
+    .tvOS(.v16),
   ],
   products: [
     // Products define the executables and libraries a package produces, making them visible to other packages.

Sources/HTTPClient/Interface/Client+MultipartFormData.swift

@@ -126,7 +126,7 @@ extension Client {
   ///
   /// - SeeAlso: ``MultipartFormData``
   public func send(
-    multipartFormData: MultipartFormData,
+    multipartFormData: sending MultipartFormData,
     with request: HTTPRequest,
     usingThreshold encodingMemoryThreshold: UInt64 = MultipartFormData.encodingMemoryThreshold
   ) async throws -> (HTTPResponse, HTTPBody?) {

Sources/HTTPClient/Interface/ClientTransport.swift

@@ -103,7 +103,7 @@ public protocol ClientTransport: Sendable {
   /// - Throws: An error if sending the request and receiving the response fails.
   func send(
     _ request: HTTPRequest,
-    body: HTTPBody?,
+    body: sending HTTPBody?,
     baseURL: URL
   ) async throws -> (HTTPResponse, HTTPBody?)
 }
@@ -207,8 +207,8 @@ public protocol ClientMiddleware: Sendable {
   /// - Throws: An error if interception of the request and response fails.
   func intercept(
     _ request: HTTPRequest,
-    body: HTTPBody?,
+    body: sending HTTPBody?,
     baseURL: URL,
-    next: @Sendable (HTTPRequest, HTTPBody?, URL) async throws -> (HTTPResponse, HTTPBody?)
+    next: @Sendable (HTTPRequest, sending HTTPBody?, URL) async throws -> (HTTPResponse, HTTPBody?)
   ) async throws -> (HTTPResponse, HTTPBody?)
 }

Sources/HTTPClient/Interface/MultipartFormData.swift

@@ -31,7 +31,7 @@ import HTTPTypes
 /// - https://www.w3.org/TR/html401/interact/forms.html#h-17.13
 ///
 /// > Note: This implementation is adapted from Alamofire's MultipartFormData implementation.
-public final class MultipartFormData: Sendable {
+public final class MultipartFormData {
   // MARK: - Helper Types
 
   enum EncodingCharacters {
@@ -65,7 +65,7 @@ public final class MultipartFormData: Sendable {
     }
   }
 
-  final class BodyPart: @unchecked Sendable {
+  final class BodyPart {
     let headers: HTTPFields
     let bodyStream: InputStream
     let bodyContentLength: UInt64
@@ -85,7 +85,7 @@ public final class MultipartFormData: Sendable {
     public let reason: Reason
 
     /// The detailed reason for the encoding failure.
-    public enum Reason {
+    public enum Reason: Sendable {
       case bodyPartURLInvalid(url: URL)
       case bodyPartFilenameInvalid(in: URL)
       case bodyPartFileNotReachable(at: URL)
@@ -159,14 +159,14 @@ public final class MultipartFormData: Sendable {
 
   /// The content length of all body parts used to generate the `multipart/form-data` not including the boundaries.
   public var contentLength: UInt64 {
-    lock.withLock { bodyParts.reduce(0) { $0 + $1.bodyContentLength } }
+    bodyParts.reduce(0) { $0 + $1.bodyContentLength }
   }
 
   /// The boundary used to separate the body parts in the encoded form data.
   public let boundary: String
 
   private let fileManager: FileManager
-  private let lock = NSLock()
+  // private let lock = NSLock()
   private var bodyParts: [BodyPart] = []
   private var bodyPartError: EncodingError?
   private let streamBufferSize: Int
@@ -377,9 +377,7 @@ public final class MultipartFormData: Sendable {
   ///   - headers: `HTTPFields` for the body part.
   public func append(_ stream: InputStream, withLength length: UInt64, headers: HTTPFields) {
     let bodyPart = BodyPart(headers: headers, bodyStream: stream, bodyContentLength: length)
-    lock.withLock {
-      bodyParts.append(bodyPart)
-    }
+    bodyParts.append(bodyPart)
   }
 
   // MARK: - Data Encoding
@@ -392,19 +390,17 @@ public final class MultipartFormData: Sendable {
   ///
   /// - Returns: The encoded `Data`, if encoding is successful.
   /// - Throws:  An `EncodingError` if encoding encounters an error.
-  public func encode() throws -> Data {
+  public consuming func encode() throws -> Data {
     if let bodyPartError {
       throw bodyPartError
     }
 
     var encoded = Data()
 
-    lock.withLock {
-      bodyParts.first?.hasInitialBoundary = true
-      bodyParts.last?.hasFinalBoundary = true
-    }
+    bodyParts.first?.hasInitialBoundary = true
+    bodyParts.last?.hasFinalBoundary = true
 
-    let parts = lock.withLock { bodyParts }
+    let parts = bodyParts
     for bodyPart in parts {
       let encodedData = try encode(bodyPart)
       encoded.append(encodedData)
@@ -420,7 +416,7 @@ public final class MultipartFormData: Sendable {
   ///
   /// - Parameter fileURL: File `URL` to which to write the form data.
   /// - Throws:            An `EncodingError` if encoding encounters an error.
-  public func writeEncodedData(to fileURL: URL) throws {
+  public consuming func writeEncodedData(to fileURL: URL) throws {
     if let bodyPartError {
       throw bodyPartError
     }
@@ -438,12 +434,10 @@ public final class MultipartFormData: Sendable {
     outputStream.open()
     defer { outputStream.close() }
 
-    lock.withLock {
-      bodyParts.first?.hasInitialBoundary = true
-      bodyParts.last?.hasFinalBoundary = true
-    }
+    bodyParts.first?.hasInitialBoundary = true
+    bodyParts.last?.hasFinalBoundary = true
 
-    let parts = lock.withLock { bodyParts }
+    let parts = bodyParts
     for bodyPart in parts {
       try write(bodyPart, to: outputStream)
     }
@@ -634,10 +628,8 @@ public final class MultipartFormData: Sendable {
   // MARK: - Private - Errors
 
   private func setBodyPartError(withReason reason: EncodingError.Reason) {
-    lock.withLock {
-      guard bodyPartError == nil else { return }
-      bodyPartError = EncodingError(reason: reason)
-    }
+    guard bodyPartError == nil else { return }
+    bodyPartError = EncodingError(reason: reason)
   }
 }
 

Sources/HTTPClient/Middlewares/LoggingMiddleware.swift

@@ -19,9 +19,9 @@ public struct LoggingMiddleware: ClientMiddleware {
 
   public func intercept(
     _ request: HTTPRequest,
-    body: HTTPBody?,
+    body: sending HTTPBody?,
     baseURL: URL,
-    next: (HTTPRequest, HTTPBody?, URL) async throws -> (HTTPResponse, HTTPBody?)
+    next: (HTTPRequest, sending HTTPBody?, URL) async throws -> (HTTPResponse, HTTPBody?)
   ) async throws -> (HTTPResponse, HTTPBody?) {
     var logger = logger
     if includeMetadata, logger[metadataKey: "request-id"] == nil {

Tests/HTTPClientTests/ClientTests.swift

@@ -13,12 +13,12 @@ struct ClientTests {
   struct MockTransport: ClientTransport {
     let responseStatus: HTTPResponse.Status
     let responseBody: String?
-    var onSend: ((HTTPRequest, HTTPBody?, URL) -> Void)?
+    var onSend: (@Sendable (HTTPRequest, HTTPBody?, URL) -> Void)?
 
     init(
       responseStatus: HTTPResponse.Status = .ok,
       responseBody: String? = nil,
-      onSend: ((HTTPRequest, HTTPBody?, URL) -> Void)? = nil
+      onSend: (@Sendable (HTTPRequest, HTTPBody?, URL) -> Void)? = nil
     ) {
       self.responseStatus = responseStatus
       self.responseBody = responseBody
@@ -27,7 +27,7 @@ struct ClientTests {
 
     func send(
       _ request: HTTPRequest,
-      body: HTTPBody?,
+      body: sending HTTPBody?,
       baseURL: URL
     ) async throws -> (HTTPResponse, HTTPBody?) {
       onSend?(request, body, baseURL)
@@ -44,7 +44,7 @@ struct ClientTests {
 
     func send(
       _ request: HTTPRequest,
-      body: HTTPBody?,
+      body: sending HTTPBody?,
       baseURL: URL
     ) async throws -> (HTTPResponse, HTTPBody?) {
       throw TransportFailure()
@@ -54,17 +54,17 @@ struct ClientTests {
   /// A mock middleware for testing
   struct MockMiddleware: ClientMiddleware {
     let id: String
-    var onIntercept: ((HTTPRequest, HTTPBody?, URL) -> Void)?
+    var onIntercept: (@Sendable (HTTPRequest, HTTPBody?, URL) -> Void)?
     var shouldModifyRequest: Bool = false
     var shouldFail: Bool = false
 
     struct MiddlewareError: Error {}
 
     func intercept(
       _ request: HTTPRequest,
-      body: HTTPBody?,
+      body: sending HTTPBody?,
       baseURL: URL,
-      next: (HTTPRequest, HTTPBody?, URL) async throws -> (HTTPResponse, HTTPBody?)
+      next: (HTTPRequest, sending HTTPBody?, URL) async throws -> (HTTPResponse, HTTPBody?)
     ) async throws -> (HTTPResponse, HTTPBody?) {
       onIntercept?(request, body, baseURL)
 
@@ -125,14 +125,15 @@ struct ClientTests {
 
   @Test func sendRequestWithBody() async throws {
     let serverURL = URL(string: "https://api.example.com")!
-    var capturedBody: String?
+    let capturedBody = SendableBox<String?>(nil)
 
     let transport = MockTransport(
       responseStatus: .created,
       onSend: { _, body, _ in
         Task {
           if let body = body {
-            capturedBody = try? await String(collecting: body, upTo: 1024)
+            let value = try? await String(collecting: body, upTo: 1024)
+            capturedBody.withLock { $0 = value }
           }
         }
       }
@@ -151,11 +152,11 @@ struct ClientTests {
 
   @Test func clientPassesBaseURLToTransport() async throws {
     let serverURL = URL(string: "https://api.example.com")!
-    var capturedBaseURL: URL?
+    let capturedBaseURL = SendableBox<URL?>(nil)
 
     let transport = MockTransport(
       onSend: { _, _, baseURL in
-        capturedBaseURL = baseURL
+        capturedBaseURL.withLock { $0 = baseURL }
       }
     )
 
@@ -164,32 +165,32 @@ struct ClientTests {
     let request = HTTPRequest(method: .get, url: serverURL.appending(path: "test"))
     _ = try await client.send(request)
 
-    #expect(capturedBaseURL == serverURL)
+    #expect(capturedBaseURL.value == serverURL)
   }
 
   // MARK: - Middleware Tests
 
   @Test func middlewareExecutionOrder() async throws {
     let serverURL = URL(string: "https://api.example.com")!
-    var executionOrder: [String] = []
+    let executionOrder = SendableBox<[String]>([])
 
     let middleware1 = MockMiddleware(
       id: "m1",
       onIntercept: { _, _, _ in
-        executionOrder.append("m1")
+        executionOrder.withLock { $0.append("m1") }
       }
     )
 
     let middleware2 = MockMiddleware(
       id: "m2",
       onIntercept: { _, _, _ in
-        executionOrder.append("m2")
+        executionOrder.withLock { $0.append("m2") }
       }
     )
 
     let transport = MockTransport(
       onSend: { _, _, _ in
-        executionOrder.append("transport")
+        executionOrder.withLock { $0.append("transport") }
       }
     )
 
@@ -203,17 +204,17 @@ struct ClientTests {
     _ = try await client.send(request)
 
     // Middlewares should execute in order, then transport
-    #expect(executionOrder == ["m1", "m2", "transport"])
+    #expect(executionOrder.value == ["m1", "m2", "transport"])
   }
 
   @Test func middlewareCanModifyRequest() async throws {
     let serverURL = URL(string: "https://api.example.com")!
-    var capturedRequest: HTTPRequest?
+    let capturedRequest = SendableBox<HTTPRequest?>(nil)
 
     let middleware = MockMiddleware(id: "test", shouldModifyRequest: true)
     let transport = MockTransport(
       onSend: { request, _, _ in
-        capturedRequest = request
+        capturedRequest.withLock { $0 = request }
       }
     )
 
@@ -226,19 +227,19 @@ struct ClientTests {
     let request = HTTPRequest(method: .get, url: serverURL.appending(path: "test"))
     _ = try await client.send(request)
 
-    #expect(capturedRequest?.headerFields[.init("X-Middleware")!] == "test")
+    #expect(capturedRequest.value?.headerFields[.init("X-Middleware")!] == "test")
   }
 
   @Test func multipleMiddlewaresCanChainModifications() async throws {
     let serverURL = URL(string: "https://api.example.com")!
-    var capturedRequest: HTTPRequest?
+    let capturedRequest = SendableBox<HTTPRequest?>(nil)
 
     let middleware1 = MockMiddleware(id: "first", shouldModifyRequest: true)
     let middleware2 = MockMiddleware(id: "second", shouldModifyRequest: true)
 
     let transport = MockTransport(
       onSend: { request, _, _ in
-        capturedRequest = request
+        capturedRequest.withLock { $0 = request }
       }
     )
 
@@ -253,7 +254,7 @@ struct ClientTests {
 
     // Both middlewares should have modified the request
     // Note: The test middleware adds the same header, so we only see the last one
-    #expect(capturedRequest?.headerFields[.init("X-Middleware")!] != nil)
+    #expect(capturedRequest.value?.headerFields[.init("X-Middleware")!] != nil)
   }
 
   // MARK: - Error Handling Tests
@@ -395,6 +396,6 @@ struct ClientTests {
     }
 
     // If we got here without crashing, concurrent access works
-    #expect(true)
+    #expect(Bool(true))
   }
 }