Move test JSON (de)serializer to its own file

Author: gjcairo

Tests/GRPCNIOTransportHTTP2Tests/ControlMessages.swift

@@ -133,20 +133,3 @@ enum CancellationKind: Codable {
 
 struct Empty: Codable {
 }
-
-struct JSONSerializer<Message: Encodable>: MessageSerializer {
-  private let encoder = JSONEncoder()
-
-  func serialize(_ message: Message) throws -> [UInt8] {
-    let data = try self.encoder.encode(message)
-    return Array(data)
-  }
-}
-
-struct JSONDeserializer<Message: Decodable>: MessageDeserializer {
-  private let decoder = JSONDecoder()
-
-  func deserialize(_ serializedMessageBytes: [UInt8]) throws -> Message {
-    try self.decoder.decode(Message.self, from: Data(serializedMessageBytes))
-  }
-}

Tests/GRPCNIOTransportHTTP2Tests/Test Utilities/JSONSerializing.swift

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2025, 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 Foundation
+import GRPCCore
+
+struct JSONSerializer<Message: Encodable>: MessageSerializer {
+  private let encoder = JSONEncoder()
+
+  func serialize(_ message: Message) throws -> [UInt8] {
+    let data = try self.encoder.encode(message)
+    return Array(data)
+  }
+}
+
+struct JSONDeserializer<Message: Decodable>: MessageDeserializer {
+  private let decoder = JSONDecoder()
+
+  func deserialize(_ serializedMessageBytes: [UInt8]) throws -> Message {
+    try self.decoder.decode(Message.self, from: Data(serializedMessageBytes))
+  }
+}