/*
 * Copyright 2024, gRPC Authors All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import GRPCCodeGen
import GRPCProtobufCodeGen
import SwiftProtobufPluginLibrary
import Testing

struct ProtobufCodeGeneratorTests: UsesDescriptorSet {
  static let descriptorSetName = "test-service"
  static let fileDescriptorName = "test-service"

  @Test("Generate", arguments: [SourceGenerator.Config.AccessLevel.internal, .public, .package])
  func generate(accessLevel: SourceGenerator.Config.AccessLevel) throws {
    let generator = ProtobufCodeGenerator(
      config: SourceGenerator.Config(
        accessLevel: accessLevel,
        accessLevelOnImports: false,
        client: true,
        server: true,
        indentation: 2
      )
    )

    let access: String
    switch accessLevel {
    case .public:
      access = "public"
    case .internal:
      access = "internal"
    case .package:
      access = "package"
    default:
      fatalError()
    }

    let generated = try generator.generateCode(
      fileDescriptor: Self.fileDescriptor,
      protoFileModuleMappings: ProtoFileToModuleMappings(),
      extraModuleImports: []
    )

    let expected = """
      /// Leading trivia.

      // DO NOT EDIT.
      // swift-format-ignore-file
      //
      // Generated by the gRPC Swift generator plugin for the protocol buffer compiler.
      // Source: test-service.proto
      //
      // For information on using the generated types, please see the documentation:
      //   https://github.com/grpc/grpc-swift

      import GRPCCore
      import GRPCProtobuf
      import SwiftProtobuf

      // MARK: - test.TestService

      /// Namespace containing generated types for the "test.TestService" service.
      \(access) enum Test_TestService {
        /// Service descriptor for the "test.TestService" service.
        \(access) static let descriptor = GRPCCore.ServiceDescriptor(fullyQualifiedService: "test.TestService")
        /// Namespace for method metadata.
        \(access) enum Method {
          /// Namespace for "Unary" metadata.
          \(access) enum Unary {
            /// Request type for "Unary".
            \(access) typealias Input = Test_TestInput
            /// Response type for "Unary".
            \(access) typealias Output = Test_TestOutput
            /// Descriptor for "Unary".
            \(access) static let descriptor = GRPCCore.MethodDescriptor(
              service: GRPCCore.ServiceDescriptor(fullyQualifiedService: "test.TestService"),
              method: "Unary"
            )
          }
          /// Namespace for "ClientStreaming" metadata.
          \(access) enum ClientStreaming {
            /// Request type for "ClientStreaming".
            \(access) typealias Input = Test_TestInput
            /// Response type for "ClientStreaming".
            \(access) typealias Output = Test_TestOutput
            /// Descriptor for "ClientStreaming".
            \(access) static let descriptor = GRPCCore.MethodDescriptor(
              service: GRPCCore.ServiceDescriptor(fullyQualifiedService: "test.TestService"),
              method: "ClientStreaming"
            )
          }
          /// Namespace for "ServerStreaming" metadata.
          \(access) enum ServerStreaming {
            /// Request type for "ServerStreaming".
            \(access) typealias Input = Test_TestInput
            /// Response type for "ServerStreaming".
            \(access) typealias Output = Test_TestOutput
            /// Descriptor for "ServerStreaming".
            \(access) static let descriptor = GRPCCore.MethodDescriptor(
              service: GRPCCore.ServiceDescriptor(fullyQualifiedService: "test.TestService"),
              method: "ServerStreaming"
            )
          }
          /// Namespace for "BidirectionalStreaming" metadata.
          \(access) enum BidirectionalStreaming {
            /// Request type for "BidirectionalStreaming".
            \(access) typealias Input = Test_TestInput
            /// Response type for "BidirectionalStreaming".
            \(access) typealias Output = Test_TestOutput
            /// Descriptor for "BidirectionalStreaming".
            \(access) static let descriptor = GRPCCore.MethodDescriptor(
              service: GRPCCore.ServiceDescriptor(fullyQualifiedService: "test.TestService"),
              method: "BidirectionalStreaming"
            )
          }
          /// Descriptors for all methods in the "test.TestService" service.
          \(access) static let descriptors: [GRPCCore.MethodDescriptor] = [
            Unary.descriptor,
            ClientStreaming.descriptor,
            ServerStreaming.descriptor,
            BidirectionalStreaming.descriptor
          ]
        }
      }

      extension GRPCCore.ServiceDescriptor {
        /// Service descriptor for the "test.TestService" service.
        \(access) static let test_TestService = GRPCCore.ServiceDescriptor(fullyQualifiedService: "test.TestService")
      }

      // MARK: test.TestService (server)

      extension Test_TestService {
        /// Streaming variant of the service protocol for the "test.TestService" service.
        ///
        /// This protocol is the lowest-level of the service protocols generated for this service
        /// giving you the most flexibility over the implementation of your service. This comes at
        /// the cost of more verbose and less strict APIs. Each RPC requires you to implement it in
        /// terms of a request stream and response stream. Where only a single request or response
        /// message is expected, you are responsible for enforcing this invariant is maintained.
        ///
        /// Where possible, prefer using the stricter, less-verbose ``ServiceProtocol``
        /// or ``SimpleServiceProtocol`` instead.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Service docs.
        \(access) protocol StreamingServiceProtocol: GRPCCore.RegistrableRPCService {
          /// Handle the "Unary" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Unary docs.
          ///
          /// - Parameters:
          ///   - request: A streaming request of `Test_TestInput` messages.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          /// - Returns: A streaming response of `Test_TestOutput` messages.
          func unary(
            request: GRPCCore.StreamingServerRequest<Test_TestInput>,
            context: GRPCCore.ServerContext
          ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput>

          /// Handle the "ClientStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Client streaming docs.
          ///
          /// - Parameters:
          ///   - request: A streaming request of `Test_TestInput` messages.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          /// - Returns: A streaming response of `Test_TestOutput` messages.
          func clientStreaming(
            request: GRPCCore.StreamingServerRequest<Test_TestInput>,
            context: GRPCCore.ServerContext
          ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput>

          /// Handle the "ServerStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Server streaming docs.
          ///
          /// - Parameters:
          ///   - request: A streaming request of `Test_TestInput` messages.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          /// - Returns: A streaming response of `Test_TestOutput` messages.
          func serverStreaming(
            request: GRPCCore.StreamingServerRequest<Test_TestInput>,
            context: GRPCCore.ServerContext
          ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput>

          /// Handle the "BidirectionalStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Bidirectional streaming docs.
          ///
          /// - Parameters:
          ///   - request: A streaming request of `Test_TestInput` messages.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          /// - Returns: A streaming response of `Test_TestOutput` messages.
          func bidirectionalStreaming(
            request: GRPCCore.StreamingServerRequest<Test_TestInput>,
            context: GRPCCore.ServerContext
          ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput>
        }

        /// Service protocol for the "test.TestService" service.
        ///
        /// This protocol is higher level than ``StreamingServiceProtocol`` but lower level than
        /// the ``SimpleServiceProtocol``, it provides access to request and response metadata and
        /// trailing response metadata. If you don't need these then consider using
        /// the ``SimpleServiceProtocol``. If you need fine grained control over your RPCs then
        /// use ``StreamingServiceProtocol``.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Service docs.
        \(access) protocol ServiceProtocol: Test_TestService.StreamingServiceProtocol {
          /// Handle the "Unary" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Unary docs.
          ///
          /// - Parameters:
          ///   - request: A request containing a single `Test_TestInput` message.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          /// - Returns: A response containing a single `Test_TestOutput` message.
          func unary(
            request: GRPCCore.ServerRequest<Test_TestInput>,
            context: GRPCCore.ServerContext
          ) async throws -> GRPCCore.ServerResponse<Test_TestOutput>

          /// Handle the "ClientStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Client streaming docs.
          ///
          /// - Parameters:
          ///   - request: A streaming request of `Test_TestInput` messages.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          /// - Returns: A response containing a single `Test_TestOutput` message.
          func clientStreaming(
            request: GRPCCore.StreamingServerRequest<Test_TestInput>,
            context: GRPCCore.ServerContext
          ) async throws -> GRPCCore.ServerResponse<Test_TestOutput>

          /// Handle the "ServerStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Server streaming docs.
          ///
          /// - Parameters:
          ///   - request: A request containing a single `Test_TestInput` message.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          /// - Returns: A streaming response of `Test_TestOutput` messages.
          func serverStreaming(
            request: GRPCCore.ServerRequest<Test_TestInput>,
            context: GRPCCore.ServerContext
          ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput>

          /// Handle the "BidirectionalStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Bidirectional streaming docs.
          ///
          /// - Parameters:
          ///   - request: A streaming request of `Test_TestInput` messages.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          /// - Returns: A streaming response of `Test_TestOutput` messages.
          func bidirectionalStreaming(
            request: GRPCCore.StreamingServerRequest<Test_TestInput>,
            context: GRPCCore.ServerContext
          ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput>
        }

        /// Simple service protocol for the "test.TestService" service.
        ///
        /// This is the highest level protocol for the service. The API is the easiest to use but
        /// doesn't provide access to request or response metadata. If you need access to these
        /// then use ``ServiceProtocol`` instead.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Service docs.
        \(access) protocol SimpleServiceProtocol: Test_TestService.ServiceProtocol {
          /// Handle the "Unary" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Unary docs.
          ///
          /// - Parameters:
          ///   - request: A `Test_TestInput` message.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          /// - Returns: A `Test_TestOutput` to respond with.
          func unary(
            request: Test_TestInput,
            context: GRPCCore.ServerContext
          ) async throws -> Test_TestOutput

          /// Handle the "ClientStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Client streaming docs.
          ///
          /// - Parameters:
          ///   - request: A stream of `Test_TestInput` messages.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          /// - Returns: A `Test_TestOutput` to respond with.
          func clientStreaming(
            request: GRPCCore.RPCAsyncSequence<Test_TestInput, any Swift.Error>,
            context: GRPCCore.ServerContext
          ) async throws -> Test_TestOutput

          /// Handle the "ServerStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Server streaming docs.
          ///
          /// - Parameters:
          ///   - request: A `Test_TestInput` message.
          ///   - response: A response stream of `Test_TestOutput` messages.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          func serverStreaming(
            request: Test_TestInput,
            response: GRPCCore.RPCWriter<Test_TestOutput>,
            context: GRPCCore.ServerContext
          ) async throws

          /// Handle the "BidirectionalStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Bidirectional streaming docs.
          ///
          /// - Parameters:
          ///   - request: A stream of `Test_TestInput` messages.
          ///   - response: A response stream of `Test_TestOutput` messages.
          ///   - context: Context providing information about the RPC.
          /// - Throws: Any error which occurred during the processing of the request. Thrown errors
          ///     of type `RPCError` are mapped to appropriate statuses. All other errors are converted
          ///     to an internal error.
          func bidirectionalStreaming(
            request: GRPCCore.RPCAsyncSequence<Test_TestInput, any Swift.Error>,
            response: GRPCCore.RPCWriter<Test_TestOutput>,
            context: GRPCCore.ServerContext
          ) async throws
        }
      }

      // Default implementation of 'registerMethods(with:)'.
      extension Test_TestService.StreamingServiceProtocol {
        \(access) func registerMethods(with router: inout GRPCCore.RPCRouter) {
          router.registerHandler(
            forMethod: Test_TestService.Method.Unary.descriptor,
            deserializer: GRPCProtobuf.ProtobufDeserializer<Test_TestInput>(),
            serializer: GRPCProtobuf.ProtobufSerializer<Test_TestOutput>(),
            handler: { request, context in
              try await self.unary(
                request: request,
                context: context
              )
            }
          )
          router.registerHandler(
            forMethod: Test_TestService.Method.ClientStreaming.descriptor,
            deserializer: GRPCProtobuf.ProtobufDeserializer<Test_TestInput>(),
            serializer: GRPCProtobuf.ProtobufSerializer<Test_TestOutput>(),
            handler: { request, context in
              try await self.clientStreaming(
                request: request,
                context: context
              )
            }
          )
          router.registerHandler(
            forMethod: Test_TestService.Method.ServerStreaming.descriptor,
            deserializer: GRPCProtobuf.ProtobufDeserializer<Test_TestInput>(),
            serializer: GRPCProtobuf.ProtobufSerializer<Test_TestOutput>(),
            handler: { request, context in
              try await self.serverStreaming(
                request: request,
                context: context
              )
            }
          )
          router.registerHandler(
            forMethod: Test_TestService.Method.BidirectionalStreaming.descriptor,
            deserializer: GRPCProtobuf.ProtobufDeserializer<Test_TestInput>(),
            serializer: GRPCProtobuf.ProtobufSerializer<Test_TestOutput>(),
            handler: { request, context in
              try await self.bidirectionalStreaming(
                request: request,
                context: context
              )
            }
          )
        }
      }

      // Default implementation of streaming methods from 'StreamingServiceProtocol'.
      extension Test_TestService.ServiceProtocol {
        \(access) func unary(
          request: GRPCCore.StreamingServerRequest<Test_TestInput>,
          context: GRPCCore.ServerContext
        ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput> {
          let response = try await self.unary(
            request: GRPCCore.ServerRequest(stream: request),
            context: context
          )
          return GRPCCore.StreamingServerResponse(single: response)
        }

        \(access) func clientStreaming(
          request: GRPCCore.StreamingServerRequest<Test_TestInput>,
          context: GRPCCore.ServerContext
        ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput> {
          let response = try await self.clientStreaming(
            request: request,
            context: context
          )
          return GRPCCore.StreamingServerResponse(single: response)
        }

        \(access) func serverStreaming(
          request: GRPCCore.StreamingServerRequest<Test_TestInput>,
          context: GRPCCore.ServerContext
        ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput> {
          let response = try await self.serverStreaming(
            request: GRPCCore.ServerRequest(stream: request),
            context: context
          )
          return response
        }
      }

      // Default implementation of methods from 'ServiceProtocol'.
      extension Test_TestService.SimpleServiceProtocol {
        \(access) func unary(
          request: GRPCCore.ServerRequest<Test_TestInput>,
          context: GRPCCore.ServerContext
        ) async throws -> GRPCCore.ServerResponse<Test_TestOutput> {
          return GRPCCore.ServerResponse<Test_TestOutput>(
            message: try await self.unary(
              request: request.message,
              context: context
            ),
            metadata: [:]
          )
        }

        \(access) func clientStreaming(
          request: GRPCCore.StreamingServerRequest<Test_TestInput>,
          context: GRPCCore.ServerContext
        ) async throws -> GRPCCore.ServerResponse<Test_TestOutput> {
          return GRPCCore.ServerResponse<Test_TestOutput>(
            message: try await self.clientStreaming(
              request: request.messages,
              context: context
            ),
            metadata: [:]
          )
        }

        \(access) func serverStreaming(
          request: GRPCCore.ServerRequest<Test_TestInput>,
          context: GRPCCore.ServerContext
        ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput> {
          return GRPCCore.StreamingServerResponse<Test_TestOutput>(
            metadata: [:],
            producer: { writer in
              try await self.serverStreaming(
                request: request.message,
                response: writer,
                context: context
              )
              return [:]
            }
          )
        }

        \(access) func bidirectionalStreaming(
          request: GRPCCore.StreamingServerRequest<Test_TestInput>,
          context: GRPCCore.ServerContext
        ) async throws -> GRPCCore.StreamingServerResponse<Test_TestOutput> {
          return GRPCCore.StreamingServerResponse<Test_TestOutput>(
            metadata: [:],
            producer: { writer in
              try await self.bidirectionalStreaming(
                request: request.messages,
                response: writer,
                context: context
              )
              return [:]
            }
          )
        }
      }

      // MARK: test.TestService (client)

      extension Test_TestService {
        /// Generated client protocol for the "test.TestService" service.
        ///
        /// You don't need to implement this protocol directly, use the generated
        /// implementation, ``Client``.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Service docs.
        \(access) protocol ClientProtocol: Sendable {
          /// Call the "Unary" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Unary docs.
          ///
          /// - Parameters:
          ///   - request: A request containing a single `Test_TestInput` message.
          ///   - serializer: A serializer for `Test_TestInput` messages.
          ///   - deserializer: A deserializer for `Test_TestOutput` messages.
          ///   - options: Options to apply to this RPC.
          ///   - handleResponse: A closure which handles the response, the result of which is
          ///       returned to the caller. Returning from the closure will cancel the RPC if it
          ///       hasn't already finished.
          /// - Returns: The result of `handleResponse`.
          func unary<Result>(
            request: GRPCCore.ClientRequest<Test_TestInput>,
            serializer: some GRPCCore.MessageSerializer<Test_TestInput>,
            deserializer: some GRPCCore.MessageDeserializer<Test_TestOutput>,
            options: GRPCCore.CallOptions,
            onResponse handleResponse: @Sendable @escaping (GRPCCore.ClientResponse<Test_TestOutput>) async throws -> Result
          ) async throws -> Result where Result: Sendable

          /// Call the "ClientStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Client streaming docs.
          ///
          /// - Parameters:
          ///   - request: A streaming request producing `Test_TestInput` messages.
          ///   - serializer: A serializer for `Test_TestInput` messages.
          ///   - deserializer: A deserializer for `Test_TestOutput` messages.
          ///   - options: Options to apply to this RPC.
          ///   - handleResponse: A closure which handles the response, the result of which is
          ///       returned to the caller. Returning from the closure will cancel the RPC if it
          ///       hasn't already finished.
          /// - Returns: The result of `handleResponse`.
          func clientStreaming<Result>(
            request: GRPCCore.StreamingClientRequest<Test_TestInput>,
            serializer: some GRPCCore.MessageSerializer<Test_TestInput>,
            deserializer: some GRPCCore.MessageDeserializer<Test_TestOutput>,
            options: GRPCCore.CallOptions,
            onResponse handleResponse: @Sendable @escaping (GRPCCore.ClientResponse<Test_TestOutput>) async throws -> Result
          ) async throws -> Result where Result: Sendable

          /// Call the "ServerStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Server streaming docs.
          ///
          /// - Parameters:
          ///   - request: A request containing a single `Test_TestInput` message.
          ///   - serializer: A serializer for `Test_TestInput` messages.
          ///   - deserializer: A deserializer for `Test_TestOutput` messages.
          ///   - options: Options to apply to this RPC.
          ///   - handleResponse: A closure which handles the response, the result of which is
          ///       returned to the caller. Returning from the closure will cancel the RPC if it
          ///       hasn't already finished.
          /// - Returns: The result of `handleResponse`.
          func serverStreaming<Result>(
            request: GRPCCore.ClientRequest<Test_TestInput>,
            serializer: some GRPCCore.MessageSerializer<Test_TestInput>,
            deserializer: some GRPCCore.MessageDeserializer<Test_TestOutput>,
            options: GRPCCore.CallOptions,
            onResponse handleResponse: @Sendable @escaping (GRPCCore.StreamingClientResponse<Test_TestOutput>) async throws -> Result
          ) async throws -> Result where Result: Sendable

          /// Call the "BidirectionalStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Bidirectional streaming docs.
          ///
          /// - Parameters:
          ///   - request: A streaming request producing `Test_TestInput` messages.
          ///   - serializer: A serializer for `Test_TestInput` messages.
          ///   - deserializer: A deserializer for `Test_TestOutput` messages.
          ///   - options: Options to apply to this RPC.
          ///   - handleResponse: A closure which handles the response, the result of which is
          ///       returned to the caller. Returning from the closure will cancel the RPC if it
          ///       hasn't already finished.
          /// - Returns: The result of `handleResponse`.
          func bidirectionalStreaming<Result>(
            request: GRPCCore.StreamingClientRequest<Test_TestInput>,
            serializer: some GRPCCore.MessageSerializer<Test_TestInput>,
            deserializer: some GRPCCore.MessageDeserializer<Test_TestOutput>,
            options: GRPCCore.CallOptions,
            onResponse handleResponse: @Sendable @escaping (GRPCCore.StreamingClientResponse<Test_TestOutput>) async throws -> Result
          ) async throws -> Result where Result: Sendable
        }

        /// Generated client for the "test.TestService" service.
        ///
        /// The ``Client`` provides an implementation of ``ClientProtocol`` which wraps
        /// a `GRPCCore.GRPCCClient`. The underlying `GRPCClient` provides the long-lived
        /// means of communication with the remote peer.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Service docs.
        \(access) struct Client: ClientProtocol {
          private let client: GRPCCore.GRPCClient

          /// Creates a new client wrapping the provided `GRPCCore.GRPCClient`.
          ///
          /// - Parameters:
          ///   - client: A `GRPCCore.GRPCClient` providing a communication channel to the service.
          \(access) init(wrapping client: GRPCCore.GRPCClient) {
            self.client = client
          }

          /// Call the "Unary" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Unary docs.
          ///
          /// - Parameters:
          ///   - request: A request containing a single `Test_TestInput` message.
          ///   - serializer: A serializer for `Test_TestInput` messages.
          ///   - deserializer: A deserializer for `Test_TestOutput` messages.
          ///   - options: Options to apply to this RPC.
          ///   - handleResponse: A closure which handles the response, the result of which is
          ///       returned to the caller. Returning from the closure will cancel the RPC if it
          ///       hasn't already finished.
          /// - Returns: The result of `handleResponse`.
          \(access) func unary<Result>(
            request: GRPCCore.ClientRequest<Test_TestInput>,
            serializer: some GRPCCore.MessageSerializer<Test_TestInput>,
            deserializer: some GRPCCore.MessageDeserializer<Test_TestOutput>,
            options: GRPCCore.CallOptions = .defaults,
            onResponse handleResponse: @Sendable @escaping (GRPCCore.ClientResponse<Test_TestOutput>) async throws -> Result = { response in
              try response.message
            }
          ) async throws -> Result where Result: Sendable {
            try await self.client.unary(
              request: request,
              descriptor: Test_TestService.Method.Unary.descriptor,
              serializer: serializer,
              deserializer: deserializer,
              options: options,
              onResponse: handleResponse
            )
          }

          /// Call the "ClientStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Client streaming docs.
          ///
          /// - Parameters:
          ///   - request: A streaming request producing `Test_TestInput` messages.
          ///   - serializer: A serializer for `Test_TestInput` messages.
          ///   - deserializer: A deserializer for `Test_TestOutput` messages.
          ///   - options: Options to apply to this RPC.
          ///   - handleResponse: A closure which handles the response, the result of which is
          ///       returned to the caller. Returning from the closure will cancel the RPC if it
          ///       hasn't already finished.
          /// - Returns: The result of `handleResponse`.
          \(access) func clientStreaming<Result>(
            request: GRPCCore.StreamingClientRequest<Test_TestInput>,
            serializer: some GRPCCore.MessageSerializer<Test_TestInput>,
            deserializer: some GRPCCore.MessageDeserializer<Test_TestOutput>,
            options: GRPCCore.CallOptions = .defaults,
            onResponse handleResponse: @Sendable @escaping (GRPCCore.ClientResponse<Test_TestOutput>) async throws -> Result = { response in
              try response.message
            }
          ) async throws -> Result where Result: Sendable {
            try await self.client.clientStreaming(
              request: request,
              descriptor: Test_TestService.Method.ClientStreaming.descriptor,
              serializer: serializer,
              deserializer: deserializer,
              options: options,
              onResponse: handleResponse
            )
          }

          /// Call the "ServerStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Server streaming docs.
          ///
          /// - Parameters:
          ///   - request: A request containing a single `Test_TestInput` message.
          ///   - serializer: A serializer for `Test_TestInput` messages.
          ///   - deserializer: A deserializer for `Test_TestOutput` messages.
          ///   - options: Options to apply to this RPC.
          ///   - handleResponse: A closure which handles the response, the result of which is
          ///       returned to the caller. Returning from the closure will cancel the RPC if it
          ///       hasn't already finished.
          /// - Returns: The result of `handleResponse`.
          \(access) func serverStreaming<Result>(
            request: GRPCCore.ClientRequest<Test_TestInput>,
            serializer: some GRPCCore.MessageSerializer<Test_TestInput>,
            deserializer: some GRPCCore.MessageDeserializer<Test_TestOutput>,
            options: GRPCCore.CallOptions = .defaults,
            onResponse handleResponse: @Sendable @escaping (GRPCCore.StreamingClientResponse<Test_TestOutput>) async throws -> Result
          ) async throws -> Result where Result: Sendable {
            try await self.client.serverStreaming(
              request: request,
              descriptor: Test_TestService.Method.ServerStreaming.descriptor,
              serializer: serializer,
              deserializer: deserializer,
              options: options,
              onResponse: handleResponse
            )
          }

          /// Call the "BidirectionalStreaming" method.
          ///
          /// > Source IDL Documentation:
          /// >
          /// > Bidirectional streaming docs.
          ///
          /// - Parameters:
          ///   - request: A streaming request producing `Test_TestInput` messages.
          ///   - serializer: A serializer for `Test_TestInput` messages.
          ///   - deserializer: A deserializer for `Test_TestOutput` messages.
          ///   - options: Options to apply to this RPC.
          ///   - handleResponse: A closure which handles the response, the result of which is
          ///       returned to the caller. Returning from the closure will cancel the RPC if it
          ///       hasn't already finished.
          /// - Returns: The result of `handleResponse`.
          \(access) func bidirectionalStreaming<Result>(
            request: GRPCCore.StreamingClientRequest<Test_TestInput>,
            serializer: some GRPCCore.MessageSerializer<Test_TestInput>,
            deserializer: some GRPCCore.MessageDeserializer<Test_TestOutput>,
            options: GRPCCore.CallOptions = .defaults,
            onResponse handleResponse: @Sendable @escaping (GRPCCore.StreamingClientResponse<Test_TestOutput>) async throws -> Result
          ) async throws -> Result where Result: Sendable {
            try await self.client.bidirectionalStreaming(
              request: request,
              descriptor: Test_TestService.Method.BidirectionalStreaming.descriptor,
              serializer: serializer,
              deserializer: deserializer,
              options: options,
              onResponse: handleResponse
            )
          }
        }
      }

      // Helpers providing default arguments to 'ClientProtocol' methods.
      extension Test_TestService.ClientProtocol {
        /// Call the "Unary" method.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Unary docs.
        ///
        /// - Parameters:
        ///   - request: A request containing a single `Test_TestInput` message.
        ///   - options: Options to apply to this RPC.
        ///   - handleResponse: A closure which handles the response, the result of which is
        ///       returned to the caller. Returning from the closure will cancel the RPC if it
        ///       hasn't already finished.
        /// - Returns: The result of `handleResponse`.
        \(access) func unary<Result>(
          request: GRPCCore.ClientRequest<Test_TestInput>,
          options: GRPCCore.CallOptions = .defaults,
          onResponse handleResponse: @Sendable @escaping (GRPCCore.ClientResponse<Test_TestOutput>) async throws -> Result = { response in
            try response.message
          }
        ) async throws -> Result where Result: Sendable {
          try await self.unary(
            request: request,
            serializer: GRPCProtobuf.ProtobufSerializer<Test_TestInput>(),
            deserializer: GRPCProtobuf.ProtobufDeserializer<Test_TestOutput>(),
            options: options,
            onResponse: handleResponse
          )
        }

        /// Call the "ClientStreaming" method.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Client streaming docs.
        ///
        /// - Parameters:
        ///   - request: A streaming request producing `Test_TestInput` messages.
        ///   - options: Options to apply to this RPC.
        ///   - handleResponse: A closure which handles the response, the result of which is
        ///       returned to the caller. Returning from the closure will cancel the RPC if it
        ///       hasn't already finished.
        /// - Returns: The result of `handleResponse`.
        \(access) func clientStreaming<Result>(
          request: GRPCCore.StreamingClientRequest<Test_TestInput>,
          options: GRPCCore.CallOptions = .defaults,
          onResponse handleResponse: @Sendable @escaping (GRPCCore.ClientResponse<Test_TestOutput>) async throws -> Result = { response in
            try response.message
          }
        ) async throws -> Result where Result: Sendable {
          try await self.clientStreaming(
            request: request,
            serializer: GRPCProtobuf.ProtobufSerializer<Test_TestInput>(),
            deserializer: GRPCProtobuf.ProtobufDeserializer<Test_TestOutput>(),
            options: options,
            onResponse: handleResponse
          )
        }

        /// Call the "ServerStreaming" method.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Server streaming docs.
        ///
        /// - Parameters:
        ///   - request: A request containing a single `Test_TestInput` message.
        ///   - options: Options to apply to this RPC.
        ///   - handleResponse: A closure which handles the response, the result of which is
        ///       returned to the caller. Returning from the closure will cancel the RPC if it
        ///       hasn't already finished.
        /// - Returns: The result of `handleResponse`.
        \(access) func serverStreaming<Result>(
          request: GRPCCore.ClientRequest<Test_TestInput>,
          options: GRPCCore.CallOptions = .defaults,
          onResponse handleResponse: @Sendable @escaping (GRPCCore.StreamingClientResponse<Test_TestOutput>) async throws -> Result
        ) async throws -> Result where Result: Sendable {
          try await self.serverStreaming(
            request: request,
            serializer: GRPCProtobuf.ProtobufSerializer<Test_TestInput>(),
            deserializer: GRPCProtobuf.ProtobufDeserializer<Test_TestOutput>(),
            options: options,
            onResponse: handleResponse
          )
        }

        /// Call the "BidirectionalStreaming" method.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Bidirectional streaming docs.
        ///
        /// - Parameters:
        ///   - request: A streaming request producing `Test_TestInput` messages.
        ///   - options: Options to apply to this RPC.
        ///   - handleResponse: A closure which handles the response, the result of which is
        ///       returned to the caller. Returning from the closure will cancel the RPC if it
        ///       hasn't already finished.
        /// - Returns: The result of `handleResponse`.
        \(access) func bidirectionalStreaming<Result>(
          request: GRPCCore.StreamingClientRequest<Test_TestInput>,
          options: GRPCCore.CallOptions = .defaults,
          onResponse handleResponse: @Sendable @escaping (GRPCCore.StreamingClientResponse<Test_TestOutput>) async throws -> Result
        ) async throws -> Result where Result: Sendable {
          try await self.bidirectionalStreaming(
            request: request,
            serializer: GRPCProtobuf.ProtobufSerializer<Test_TestInput>(),
            deserializer: GRPCProtobuf.ProtobufDeserializer<Test_TestOutput>(),
            options: options,
            onResponse: handleResponse
          )
        }
      }

      // Helpers providing sugared APIs for 'ClientProtocol' methods.
      extension Test_TestService.ClientProtocol {
        /// Call the "Unary" method.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Unary docs.
        ///
        /// - Parameters:
        ///   - message: request message to send.
        ///   - metadata: Additional metadata to send, defaults to empty.
        ///   - options: Options to apply to this RPC, defaults to `.defaults`.
        ///   - handleResponse: A closure which handles the response, the result of which is
        ///       returned to the caller. Returning from the closure will cancel the RPC if it
        ///       hasn't already finished.
        /// - Returns: The result of `handleResponse`.
        \(access) func unary<Result>(
          _ message: Test_TestInput,
          metadata: GRPCCore.Metadata = [:],
          options: GRPCCore.CallOptions = .defaults,
          onResponse handleResponse: @Sendable @escaping (GRPCCore.ClientResponse<Test_TestOutput>) async throws -> Result = { response in
            try response.message
          }
        ) async throws -> Result where Result: Sendable {
          let request = GRPCCore.ClientRequest<Test_TestInput>(
            message: message,
            metadata: metadata
          )
          return try await self.unary(
            request: request,
            options: options,
            onResponse: handleResponse
          )
        }

        /// Call the "ClientStreaming" method.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Client streaming docs.
        ///
        /// - Parameters:
        ///   - metadata: Additional metadata to send, defaults to empty.
        ///   - options: Options to apply to this RPC, defaults to `.defaults`.
        ///   - producer: A closure producing request messages to send to the server. The request
        ///       stream is closed when the closure returns.
        ///   - handleResponse: A closure which handles the response, the result of which is
        ///       returned to the caller. Returning from the closure will cancel the RPC if it
        ///       hasn't already finished.
        /// - Returns: The result of `handleResponse`.
        \(access) func clientStreaming<Result>(
          metadata: GRPCCore.Metadata = [:],
          options: GRPCCore.CallOptions = .defaults,
          requestProducer producer: @Sendable @escaping (GRPCCore.RPCWriter<Test_TestInput>) async throws -> Void,
          onResponse handleResponse: @Sendable @escaping (GRPCCore.ClientResponse<Test_TestOutput>) async throws -> Result = { response in
            try response.message
          }
        ) async throws -> Result where Result: Sendable {
          let request = GRPCCore.StreamingClientRequest<Test_TestInput>(
            metadata: metadata,
            producer: producer
          )
          return try await self.clientStreaming(
            request: request,
            options: options,
            onResponse: handleResponse
          )
        }

        /// Call the "ServerStreaming" method.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Server streaming docs.
        ///
        /// - Parameters:
        ///   - message: request message to send.
        ///   - metadata: Additional metadata to send, defaults to empty.
        ///   - options: Options to apply to this RPC, defaults to `.defaults`.
        ///   - handleResponse: A closure which handles the response, the result of which is
        ///       returned to the caller. Returning from the closure will cancel the RPC if it
        ///       hasn't already finished.
        /// - Returns: The result of `handleResponse`.
        \(access) func serverStreaming<Result>(
          _ message: Test_TestInput,
          metadata: GRPCCore.Metadata = [:],
          options: GRPCCore.CallOptions = .defaults,
          onResponse handleResponse: @Sendable @escaping (GRPCCore.StreamingClientResponse<Test_TestOutput>) async throws -> Result
        ) async throws -> Result where Result: Sendable {
          let request = GRPCCore.ClientRequest<Test_TestInput>(
            message: message,
            metadata: metadata
          )
          return try await self.serverStreaming(
            request: request,
            options: options,
            onResponse: handleResponse
          )
        }

        /// Call the "BidirectionalStreaming" method.
        ///
        /// > Source IDL Documentation:
        /// >
        /// > Bidirectional streaming docs.
        ///
        /// - Parameters:
        ///   - metadata: Additional metadata to send, defaults to empty.
        ///   - options: Options to apply to this RPC, defaults to `.defaults`.
        ///   - producer: A closure producing request messages to send to the server. The request
        ///       stream is closed when the closure returns.
        ///   - handleResponse: A closure which handles the response, the result of which is
        ///       returned to the caller. Returning from the closure will cancel the RPC if it
        ///       hasn't already finished.
        /// - Returns: The result of `handleResponse`.
        \(access) func bidirectionalStreaming<Result>(
          metadata: GRPCCore.Metadata = [:],
          options: GRPCCore.CallOptions = .defaults,
          requestProducer producer: @Sendable @escaping (GRPCCore.RPCWriter<Test_TestInput>) async throws -> Void,
          onResponse handleResponse: @Sendable @escaping (GRPCCore.StreamingClientResponse<Test_TestOutput>) async throws -> Result
        ) async throws -> Result where Result: Sendable {
          let request = GRPCCore.StreamingClientRequest<Test_TestInput>(
            metadata: metadata,
            producer: producer
          )
          return try await self.bidirectionalStreaming(
            request: request,
            options: options,
            onResponse: handleResponse
          )
        }
      }
      """

    #expect(generated == expected)
  }
}