fix(agents/contracts): return cloned task snapshots from shared task board

js/agents/core/contracts/shared-task-board.js

@@ -18,6 +18,7 @@
  */
 
 import { TaskStatus } from './agent-message.js';
+import { deepClone } from '../../shared/utils/value-utils.js';
 
 // ─── 常量 ───────────────────────────────────────────────
 
@@ -43,6 +44,16 @@ function createTaskId() {
   return `task_${Date.now().toString(36)}_${(++_counter).toString(36)}`;
 }
 
+/** @param {BoardTask} task @returns {BoardTask} */
+function cloneTask(task) {
+  return deepClone(task);
+}
+
+/** @param {BoardTask[]} tasks @returns {BoardTask[]} */
+function cloneTasks(tasks) {
+  return tasks.map((task) => cloneTask(task));
+}
+
 // ─── 类型定义 ───────────────────────────────────────────
 
 /**
@@ -112,7 +123,7 @@ export class SharedTaskBoard {
 
     this._tasks.set(task.id, task);
     this._emit(TaskBoardEvents.TASK_ADDED, { task });
-    return { ok: true, task };
+    return { ok: true, task: cloneTask(task) };
   }
 
   /**
@@ -136,7 +147,7 @@ export class SharedTaskBoard {
     task.claimedAt = Date.now();
 
     this._emit(TaskBoardEvents.TASK_CLAIMED, { task });
-    return { ok: true, task };
+    return { ok: true, task: cloneTask(task) };
   }
 
   /**
@@ -159,7 +170,7 @@ export class SharedTaskBoard {
     task.completedAt = Date.now();
 
     this._emit(TaskBoardEvents.TASK_COMPLETED, { task });
-    return { ok: true, task };
+    return { ok: true, task: cloneTask(task) };
   }
 
   /**
@@ -182,7 +193,7 @@ export class SharedTaskBoard {
     task.completedAt = Date.now();
 
     this._emit(TaskBoardEvents.TASK_FAILED, { task });
-    return { ok: true, task };
+    return { ok: true, task: cloneTask(task) };
   }
 
   /**
@@ -207,7 +218,7 @@ export class SharedTaskBoard {
     task.completedAt = Date.now();
 
     this._emit(TaskBoardEvents.TASK_CANCELLED, { task });
-    return { ok: true, task };
+    return { ok: true, task: cloneTask(task) };
   }
 
   /**
@@ -219,7 +230,8 @@ export class SharedTaskBoard {
     for (const task of this._tasks.values()) {
       if (task.status === 'pending') pending.push(task);
     }
-    return pending.sort((a, b) => a.priority - b.priority || a.createdAt - b.createdAt);
+    pending.sort((a, b) => a.priority - b.priority || a.createdAt - b.createdAt);
+    return cloneTasks(pending);
   }
 
   /**
@@ -234,7 +246,7 @@ export class SharedTaskBoard {
     for (const task of this._tasks.values()) {
       if (task.claimedBy === agent) result.push(task);
     }
-    return result;
+    return cloneTasks(result);
   }
 
   /**
@@ -243,7 +255,8 @@ export class SharedTaskBoard {
    * @returns {BoardTask | null}
    */
   getTask(taskId) {
-    return this._tasks.get(taskId) ?? null;
+    const task = this._tasks.get(taskId);
+    return task ? cloneTask(task) : null;
   }
 
   /** @returns {number} */
@@ -256,7 +269,7 @@ export class SharedTaskBoard {
   getSnapshot() {
     return {
       boardId: this.boardId,
-      tasks: Array.from(this._tasks.values()),
+      tasks: cloneTasks(Array.from(this._tasks.values())),
       ts: Date.now(),
     };
   }
@@ -274,7 +287,7 @@ export class SharedTaskBoard {
     let count = 0;
     for (const task of snapshot.tasks) {
       if (task && typeof task === 'object' && str(task.id)) {
-        this._tasks.set(task.id, { ...task });
+        this._tasks.set(task.id, cloneTask(task));
         count++;
       }
     }
@@ -289,10 +302,11 @@ export class SharedTaskBoard {
   _emit(eventName, payload) {
     if (!this._eventBus || typeof this._eventBus.emit !== 'function') return;
     try {
+      const safePayload = deepClone(payload);
       this._eventBus.emit(eventName, {
         actor: 'taskboard',
         status: 'info',
-        payload: { ...payload, boardId: this.boardId },
+        payload: { ...safePayload, boardId: this.boardId },
       });
     } catch {
       // best-effort

tests/unit/agents/core/contracts/shared-task-board.test.js

@@ -201,14 +201,30 @@ describe('SharedTaskBoard', () => {
   });
 
   describe('getTask', () => {
-    it('returns task by id', () => {
+    it('returns cloned task by id', () => {
       const { task } = board.addTask({ taskType: 'a:b', createdBy: 'x' });
-      expect(board.getTask(task.id)).toBe(task);
+      const stored = board.getTask(task.id);
+      expect(stored).toEqual(task);
+      expect(stored).not.toBe(task);
     });
 
     it('returns null for unknown id', () => {
       expect(board.getTask('nope')).toBeNull();
     });
+
+    it('does not allow external mutation through returned task objects', () => {
+      const { task } = board.addTask({
+        taskType: 'a:b',
+        createdBy: 'x',
+        payload: { nested: { value: 1 } },
+      });
+
+      const view = board.getTask(task.id);
+      view.payload.nested.value = 999;
+
+      const fresh = board.getTask(task.id);
+      expect(fresh.payload.nested.value).toBe(1);
+    });
   });
 
   describe('snapshot and restore', () => {
@@ -221,6 +237,10 @@ describe('SharedTaskBoard', () => {
       expect(snapshot.tasks).toHaveLength(2);
       expect(snapshot.ts).toBeGreaterThan(0);
 
+      snapshot.tasks[0].status = 'failed';
+      const fresh = board.getTask(snapshot.tasks[0].id);
+      expect(fresh.status).toBe('pending');
+
       const board2 = new SharedTaskBoard();
       const result = board2.restore(snapshot);
       expect(result.ok).toBe(true);