test(desktop): cover the busy empty-Enter double-send

apps/desktop/src/app/chat/composer/enter-submit-dom-race.test.tsx

@@ -29,7 +29,8 @@ function Harness({
   onSubmit,
   onQueue,
   onCancel,
-  onDrain
+  onDrain,
+  onSendNow
 }: {
   busy?: boolean
   disabled?: boolean
@@ -38,6 +39,7 @@ function Harness({
   onQueue: (text: string) => void
   onCancel: () => void
   onDrain: () => void
+  onSendNow?: (id: string) => void
 }) {
   const editorRef = useRef<HTMLDivElement>(null)
   const draftRef = useRef('')
@@ -103,6 +105,12 @@ function Harness({
       }
 
       if (busy && !hasLivePayload) {
+        const head = queued[0]
+
+        if (head) {
+          onSendNow?.(head)
+        }
+
         return
       }
 
@@ -167,13 +175,21 @@ describe('composer Enter submit — live DOM vs stale composer state (#39630)',
     expect(onCancel).not.toHaveBeenCalled()
   })
 
-  it('treats an empty Enter while busy as a no-op (never an accidental Stop)', async () => {
+  it('treats an empty Enter while busy with nothing queued as a no-op (never an accidental Stop)', async () => {
     const onCancel = vi.fn()
     const onSubmit = vi.fn()
     const onQueue = vi.fn()
+    const onSendNow = vi.fn()
 
     const { getByTestId } = render(
-      <Harness busy onCancel={onCancel} onDrain={vi.fn()} onQueue={onQueue} onSubmit={onSubmit} />
+      <Harness
+        busy
+        onCancel={onCancel}
+        onDrain={vi.fn()}
+        onQueue={onQueue}
+        onSendNow={onSendNow}
+        onSubmit={onSubmit}
+      />
     )
 
     const editor = getByTestId('editor')
@@ -186,6 +202,35 @@ describe('composer Enter submit — live DOM vs stale composer state (#39630)',
     expect(onCancel).not.toHaveBeenCalled()
     expect(onSubmit).not.toHaveBeenCalled()
     expect(onQueue).not.toHaveBeenCalled()
+    expect(onSendNow).not.toHaveBeenCalled()
+  })
+
+  it('double-send: an empty Enter while busy with a queued turn sends that turn now', async () => {
+    const onCancel = vi.fn()
+    const onSendNow = vi.fn()
+
+    const { getByTestId } = render(
+      <Harness
+        busy
+        onCancel={onCancel}
+        onDrain={vi.fn()}
+        onQueue={vi.fn()}
+        onSendNow={onSendNow}
+        onSubmit={vi.fn()}
+        queued={['queued-1', 'queued-2']}
+      />
+    )
+
+    const editor = getByTestId('editor')
+
+    await act(async () => {
+      editor.textContent = ''
+      fireEvent.keyDown(editor, { key: 'Enter' })
+    })
+
+    // Head of the queue, and NOT a bare cancel — send-now promotes + interrupts.
+    expect(onSendNow).toHaveBeenCalledWith('queued-1')
+    expect(onCancel).not.toHaveBeenCalled()
   })
 
   it('drains the next queued prompt on Enter when idle with a truly empty editor', async () => {