feat: implement AfterTool tail tool calls (#18486)

packages/cli/src/ui/hooks/useToolScheduler.test.ts

@@ -13,6 +13,7 @@ import {
   Scheduler,
   type Config,
   type MessageBus,
+  type ExecutingToolCall,
   type CompletedToolCall,
   type ToolCallsUpdateMessage,
   type AnyDeclarativeTool,
@@ -110,7 +111,7 @@ describe('useToolScheduler', () => {
       tool: createMockTool(),
       invocation: createMockInvocation(),
       liveOutput: 'Loading...',
-    };
+    } as ExecutingToolCall;
 
     act(() => {
       void mockMessageBus.publish({
@@ -405,4 +406,62 @@ describe('useToolScheduler', () => {
       toolCalls.find((t) => t.request.callId === 'call-sub')?.schedulerId,
     ).toBe('subagent-1');
   });
+
+  it('adapts success/error status to executing when a tail call is present', () => {
+    vi.useFakeTimers();
+    const { result } = renderHook(() =>
+      useToolScheduler(
+        vi.fn().mockResolvedValue(undefined),
+        mockConfig,
+        () => undefined,
+      ),
+    );
+
+    const startTime = Date.now();
+    vi.advanceTimersByTime(1000);
+
+    const mockToolCall = {
+      status: CoreToolCallStatus.Success as const,
+      request: {
+        callId: 'call-1',
+        name: 'test_tool',
+        args: {},
+        isClientInitiated: false,
+        prompt_id: 'p1',
+      },
+      tool: createMockTool(),
+      invocation: createMockInvocation(),
+      response: {
+        callId: 'call-1',
+        resultDisplay: 'OK',
+        responseParts: [],
+        error: undefined,
+        errorType: undefined,
+      },
+      tailToolCallRequest: {
+        name: 'tail_tool',
+        args: {},
+        isClientInitiated: false,
+        prompt_id: '123',
+      },
+    };
+
+    act(() => {
+      void mockMessageBus.publish({
+        type: MessageBusType.TOOL_CALLS_UPDATE,
+        toolCalls: [mockToolCall],
+        schedulerId: ROOT_SCHEDULER_ID,
+      } as ToolCallsUpdateMessage);
+    });
+
+    const [toolCalls, , , , , lastOutputTime] = result.current;
+
+    // Check if status has been adapted to 'executing'
+    expect(toolCalls[0].status).toBe(CoreToolCallStatus.Executing);
+
+    // Check if lastOutputTime was updated due to the transitional state
+    expect(lastOutputTime).toBeGreaterThan(startTime);
+
+    vi.useRealTimers();
+  });
 });