fix(cli): block Windows Tab approval-mode toggle when input has a Tab consumer

packages/cli/src/ui/AppContainer.tsx

@@ -1219,8 +1219,11 @@ export const AppContainer = (props: AppContainerProps) => {
     hideTips: tipsDisabled,
   });
 
-  // Track whether suggestions are visible for Tab key handling
-  const [hasSuggestionsVisible, setHasSuggestionsVisible] = useState(false);
+  // Track whether the input area has any Tab consumer (autocomplete dropdown,
+  // followup suggestion, mid-input ghost text, reverse/command search). When
+  // true, we suppress the Windows-only "bare Tab cycles approval mode"
+  // fallback so a single Tab keystroke triggers only one action. See #4171.
+  const [hasTabConsumer, setHasTabConsumer] = useState(false);
 
   const agentViewState = useAgentViewState();
   const { dialogOpen: bgTasksDialogOpen } = useBackgroundTaskViewState();
@@ -1246,7 +1249,7 @@ export const AppContainer = (props: AppContainerProps) => {
     config,
     addItem: historyManager.addItem,
     onApprovalModeChange: handleApprovalModeChange,
-    shouldBlockTab: () => hasSuggestionsVisible,
+    shouldBlockTab: () => hasTabConsumer,
     disabled: agentViewState.activeView !== 'main',
   });
 
@@ -3250,7 +3253,7 @@ export const AppContainer = (props: AppContainerProps) => {
       handleFolderTrustSelect,
       setConstrainHeight,
       onEscapePromptChange: handleEscapePromptChange,
-      onSuggestionsVisibilityChange: setHasSuggestionsVisible,
+      onSuggestionsVisibilityChange: setHasTabConsumer,
       refreshStatic,
       handleFinalSubmit,
       handleRetryLastPrompt: retryLastPrompt,

packages/cli/src/ui/components/InputPrompt.test.tsx

@@ -431,6 +431,158 @@ describe('InputPrompt', () => {
     });
   });
 
+  // Regression for #4171: onSuggestionsVisibilityChange (consumed by
+  // AppContainer as `shouldBlockTab`) must report `true` whenever ANY
+  // input-side handler would consume Tab — not just the autocomplete
+  // dropdown. Otherwise on Windows the bare-Tab approval-mode fallback
+  // double-fires alongside the input-side handler.
+  describe('hasTabConsumer reporting (issue #4171)', () => {
+    // Match the SUGGESTION_DELAY_MS debounce inside createFollowupController.
+    const SUGGESTION_VISIBLE_WAIT_MS = 700;
+
+    it('reports true while the followup prompt suggestion is visible', async () => {
+      const onSuggestionsVisibilityChange = vi.fn();
+      const { unmount } = renderWithProviders(
+        <InputPrompt
+          {...props}
+          promptSuggestion="commit this"
+          onSuggestionsVisibilityChange={onSuggestionsVisibilityChange}
+        />,
+      );
+      await wait(SUGGESTION_VISIBLE_WAIT_MS);
+
+      expect(onSuggestionsVisibilityChange).toHaveBeenCalledWith(true);
+      unmount();
+    });
+
+    it('reports true while mid-input ghost text offers an accept', async () => {
+      mockCommandCompletion.midInputGhostText = {
+        text: 'ile.txt',
+        insertPosition: 1,
+        acceptText: 'ile.txt',
+      };
+      const onSuggestionsVisibilityChange = vi.fn();
+      const { unmount } = renderWithProviders(
+        <InputPrompt
+          {...props}
+          onSuggestionsVisibilityChange={onSuggestionsVisibilityChange}
+        />,
+      );
+      await wait();
+
+      expect(onSuggestionsVisibilityChange).toHaveBeenCalledWith(true);
+      unmount();
+    });
+
+    it('reports true while the autocomplete dropdown is visible', async () => {
+      mockCommandCompletion.showSuggestions = true;
+      mockCommandCompletion.suggestions = [
+        {
+          value: '/clear',
+          label: '/clear',
+          description: 'Clear screen',
+        },
+      ] as UseCommandCompletionReturn['suggestions'];
+      const onSuggestionsVisibilityChange = vi.fn();
+      const { unmount } = renderWithProviders(
+        <InputPrompt
+          {...props}
+          onSuggestionsVisibilityChange={onSuggestionsVisibilityChange}
+        />,
+      );
+      await wait();
+
+      expect(onSuggestionsVisibilityChange).toHaveBeenCalledWith(true);
+      unmount();
+    });
+
+    it('reports false when the input area is idle (no dropdown, no followup, no ghost)', async () => {
+      const onSuggestionsVisibilityChange = vi.fn();
+      const { unmount } = renderWithProviders(
+        <InputPrompt
+          {...props}
+          onSuggestionsVisibilityChange={onSuggestionsVisibilityChange}
+        />,
+      );
+      await wait();
+
+      // Pin the actual value (not just "never true") — the mount-time effect
+      // must report false when nothing in the input area wants Tab.
+      expect(onSuggestionsVisibilityChange).toHaveBeenCalledWith(false);
+      expect(onSuggestionsVisibilityChange).not.toHaveBeenCalledWith(true);
+      unmount();
+    });
+
+    it('reports false again after the autocomplete dropdown is dismissed', async () => {
+      mockedUseCommandCompletion.mockReturnValue({
+        ...mockCommandCompletion,
+        showSuggestions: true,
+        suggestions: [
+          {
+            value: '/clear',
+            label: '/clear',
+            description: 'Clear screen',
+          },
+        ] as UseCommandCompletionReturn['suggestions'],
+      });
+      const onSuggestionsVisibilityChange = vi.fn();
+      const { rerender, unmount } = renderWithProviders(
+        <InputPrompt
+          {...props}
+          onSuggestionsVisibilityChange={onSuggestionsVisibilityChange}
+        />,
+      );
+      await wait();
+      expect(onSuggestionsVisibilityChange).toHaveBeenLastCalledWith(true);
+
+      // Dismiss the dropdown and re-render — Windows Tab cycling must be
+      // re-enabled. Without this transition signal, the parent would keep
+      // suppressing the approval-mode fallback after the dropdown closed.
+      mockedUseCommandCompletion.mockReturnValue(mockCommandCompletion);
+      rerender(
+        <InputPrompt
+          {...props}
+          onSuggestionsVisibilityChange={onSuggestionsVisibilityChange}
+        />,
+      );
+      await wait();
+
+      expect(onSuggestionsVisibilityChange).toHaveBeenLastCalledWith(false);
+      unmount();
+    });
+
+    it('reports false on unmount even if a Tab consumer was active', async () => {
+      // Regression for the stale-signal bug: if InputPrompt unmounts while
+      // some Tab consumer is true (e.g. streaming starts while autocomplete
+      // is open), AppContainer would otherwise keep blocking Windows Tab
+      // approval-mode cycling for the entire streaming window.
+      mockedUseCommandCompletion.mockReturnValue({
+        ...mockCommandCompletion,
+        showSuggestions: true,
+        suggestions: [
+          {
+            value: '/clear',
+            label: '/clear',
+            description: 'Clear screen',
+          },
+        ] as UseCommandCompletionReturn['suggestions'],
+      });
+      const onSuggestionsVisibilityChange = vi.fn();
+      const { unmount } = renderWithProviders(
+        <InputPrompt
+          {...props}
+          onSuggestionsVisibilityChange={onSuggestionsVisibilityChange}
+        />,
+      );
+      await wait();
+      expect(onSuggestionsVisibilityChange).toHaveBeenLastCalledWith(true);
+
+      unmount();
+      // Last call after unmount must be false — the cleanup function fires.
+      expect(onSuggestionsVisibilityChange).toHaveBeenLastCalledWith(false);
+    });
+  });
+
   it('should call shellHistory.getPreviousCommand on up arrow in shell mode', async () => {
     props.shellModeActive = true;
     const { stdin, unmount } = renderWithProviders(<InputPrompt {...props} />);

packages/cli/src/ui/components/InputPrompt.tsx

@@ -87,6 +87,16 @@ export interface InputPromptProps {
   onEscapePromptChange?: (showPrompt: boolean) => void;
   onToggleShortcuts?: () => void;
   showShortcuts?: boolean;
+  /**
+   * Reports whether any input-area Tab consumer is active — autocomplete
+   * dropdown, followup prompt suggestion, or mid-input ghost text. AppContainer
+   * feeds this into useAutoAcceptIndicator's `shouldBlockTab` to suppress the
+   * Windows-only "bare Tab cycles approval mode" fallback when an input-side
+   * handler already wants the Tab keystroke. See #4171.
+   *
+   * Name retained for backward compatibility with existing context wiring;
+   * the value tracks more than just suggestion-dropdown visibility.
+   */
   onSuggestionsVisibilityChange?: (visible: boolean) => void;
   vimHandleInput?: (key: Key) => boolean;
   isEmbeddedShellFocused?: boolean;
@@ -1418,12 +1428,29 @@ export const InputPrompt: React.FC<InputPromptProps> = ({
     (shouldUseExportSuggestions && exportCompletion.shouldShowSuggestions) ||
     activeCompletion.showSuggestions;
 
-  // Notify parent about suggestions visibility changes
+  // Whether any input-side handler would consume a Tab keystroke. The parent
+  // (AppContainer) feeds this into useAutoAcceptIndicator's `shouldBlockTab`
+  // so the Windows-only "bare Tab cycles approval mode" fallback doesn't
+  // double-fire alongside an input-area Tab handler. See issue #4171.
+  //
+  // Note on reverse/command-search: when those overlays have matches, their
+  // `showSuggestions` flag flows into `shouldShowSuggestions` above and Tab IS
+  // consumed (ACCEPT_SUGGESTION_REVERSE_SEARCH). When they are active with no
+  // matches, Tab is not consumed — so the bare `reverseSearchActive` /
+  // `commandSearchActive` flags are intentionally NOT included here.
+  const hasTabConsumer =
+    shouldShowSuggestions ||
+    (followup.state.isVisible && Boolean(followup.state.suggestion)) ||
+    Boolean(completion.midInputGhostText?.acceptText);
+
   useEffect(() => {
-    if (onSuggestionsVisibilityChange) {
-      onSuggestionsVisibilityChange(shouldShowSuggestions);
-    }
-  }, [shouldShowSuggestions, onSuggestionsVisibilityChange]);
+    onSuggestionsVisibilityChange?.(hasTabConsumer);
+    // Reset to false on unmount (e.g. when InputPrompt unmounts during
+    // streaming) so AppContainer's stale `hasTabConsumer` doesn't keep
+    // blocking Windows Tab approval-mode cycling while there is no input
+    // area to consume the keystroke.
+    return () => onSuggestionsVisibilityChange?.(false);
+  }, [hasTabConsumer, onSuggestionsVisibilityChange]);
 
   // Trigger prompt suggestion when prop changes
   useEffect(() => {