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Author: mhyeon-lee

server-common/src/main/java/io/a2a/server/tasks/TaskManager.java

@@ -104,7 +104,7 @@ public Event process(Event event) throws A2AServerException {
     }
 
     public Task updateWithMessage(Message message, Task task) {
-        List<Message> history = task.getHistory() == null ? new ArrayList<>() : new ArrayList<>(task.getHistory());
+        List<Message> history = new ArrayList<>(task.getHistory());
 
         TaskStatus status = task.getStatus();
         if (status.message() != null) {

server-common/src/test/java/io/a2a/server/tasks/TaskManagerTest.java

@@ -724,9 +724,7 @@ public void testUpdateWithMessage() throws A2AServerException {
                 .messageId("update-msg-id")
                 .build();
 
-        TaskManager taskManagerWithUpdateMessage = new TaskManager(saved.getId(), saved.getContextId(), taskStore, updateMessage);
-        Task retrieved = taskManagerWithUpdateMessage.getTask();
-        Task updated = taskManagerWithUpdateMessage.updateWithMessage(updateMessage, retrieved);
+        Task updated = taskManagerWithInitialMessage.updateWithMessage(updateMessage, saved);
 
         // There should now be a history containing the initialMessage, task message and update message
         assertNotNull(updated.getHistory());