fix(webview): ignore blank or missing follow-up suggestion answers

src/core/auto-approval/__tests__/followup.spec.ts

@@ -0,0 +1,96 @@
+import { checkAutoApproval } from ".."
+
+describe("Follow-up question auto-approval", () => {
+	const baseState = {
+		autoApprovalEnabled: true,
+		alwaysAllowFollowupQuestions: true,
+		followupAutoApproveTimeoutMs: 10_000,
+	}
+
+	const followupText = (suggest: unknown) => JSON.stringify({ question: "Pick one?", suggest }) as string
+
+	const run = (state: Record<string, unknown>, text: string) =>
+		checkAutoApproval({ state: state as never, ask: "followup", text })
+
+	it("schedules a timeout that auto-answers with the first valid suggestion", async () => {
+		const result = await run(baseState, followupText([{ answer: "Yes, proceed" }]))
+
+		expect(result.decision).toBe("timeout")
+		if (result.decision === "timeout") {
+			expect(result.timeout).toBe(10_000)
+			expect(result.fn()).toEqual({
+				askResponse: "messageResponse",
+				text: "Yes, proceed",
+			})
+		}
+	})
+
+	it("falls back to asking when the follow-up has no text payload", async () => {
+		// Exercises the `text || "{}"` fallback: a follow-up without any payload must
+		// not schedule an auto-answer timeout.
+		const result = await checkAutoApproval({ state: baseState as never, ask: "followup" })
+
+		expect(result).toEqual({ decision: "ask" })
+	})
+
+	it("skips a blank or missing first answer and uses the next valid suggestion (issue #1226)", async () => {
+		// Mirrors a malformed model response where JSON round-tripping drops
+		// `answer: undefined` and the first item is unusable.
+		const result = await run(baseState, followupText([{}, { answer: "   " }, { answer: "Valid answer" }]))
+
+		expect(result.decision).toBe("timeout")
+		if (result.decision === "timeout") {
+			expect(result.fn()).toEqual({
+				askResponse: "messageResponse",
+				text: "Valid answer",
+			})
+		}
+	})
+
+	it("falls back to asking when every suggestion answer is blank or missing (issue #1226)", async () => {
+		// Before the #1226 fix this scheduled a timeout that auto-answered the
+		// follow-up with `undefined` text, silently accepting an empty answer.
+		const result = await run(baseState, followupText([{ answer: "" }, { answer: "  \n\t " }, {}]))
+
+		expect(result).toEqual({ decision: "ask" })
+	})
+
+	it("falls back to asking when the suggestion answer is not a string", async () => {
+		const result = await run(baseState, followupText([{ answer: 42 }]))
+
+		expect(result).toEqual({ decision: "ask" })
+	})
+
+	it("falls back to asking when the follow-up has no suggestions", async () => {
+		const result = await run(baseState, JSON.stringify({ question: "Pick one?" }))
+
+		expect(result).toEqual({ decision: "ask" })
+	})
+
+	it("falls back to asking when the follow-up text is not valid JSON", async () => {
+		const result = await run(baseState, "not-json")
+
+		expect(result).toEqual({ decision: "ask" })
+	})
+
+	it("falls back to asking when the auto-approve timeout is not positive", async () => {
+		const result = await run({ ...baseState, followupAutoApproveTimeoutMs: 0 }, followupText([{ answer: "Yes" }]))
+
+		expect(result).toEqual({ decision: "ask" })
+	})
+
+	it("does not auto-approve when follow-up auto-approval is disabled", async () => {
+		const result = await run(
+			{ ...baseState, alwaysAllowFollowupQuestions: false },
+			followupText([{ answer: "Yes" }]),
+		)
+
+		expect(result).toEqual({ decision: "ask" })
+	})
+
+	it("does not auto-approve when global auto-approval is disabled", async () => {
+		const result = await run({ ...baseState, autoApprovalEnabled: false }, followupText([{ answer: "Yes" }]))
+
+		expect(result).toEqual({ decision: "ask" })
+	})
+})

src/core/auto-approval/index.ts

@@ -67,7 +67,15 @@ export async function checkAutoApproval({
 	if (ask === "followup") {
 		if (state.alwaysAllowFollowupQuestions === true) {
 			try {
-				const suggestion = (JSON.parse(text || "{}") as FollowUpData).suggest?.[0]
+				const suggestions = (JSON.parse(text || "{}") as FollowUpData).suggest ?? []
+
+				// A missing or blank answer would auto-approve the follow-up with no
+				// content after the timeout (issue #1226), so pick the first suggestion
+				// with a usable answer. This mirrors the webview's visible-suggestions
+				// filter in FollowUpSuggest.
+				const suggestion = suggestions.find(
+					(item) => typeof item?.answer === "string" && item.answer.trim().length > 0,
+				)
 
 				if (
 					suggestion &&

webview-ui/src/components/chat/ChatTextArea.tsx

@@ -82,6 +82,11 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 		},
 		ref,
 	) => {
+		// A malformed follow-up answer can push a non-string value into the input state
+		// (issue #1226). Normalize once so every string operation below (trim, slice,
+		// indexing, paste, drop, and the textarea value) is safe.
+		const normalizedInputValue = typeof inputValue === "string" ? inputValue : ""
+
 		const { t } = useAppTranslation()
 		const {
 			filePaths,
@@ -159,7 +164,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 					if (message.text && textAreaRef.current) {
 						// Insert the command text at the current cursor position
 						const textarea = textAreaRef.current
-						const currentValue = inputValue
+						const currentValue = normalizedInputValue
 						const cursorPos = textarea.selectionStart || 0
 
 						// Check if we need to add a space before the command
@@ -205,7 +210,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 
 			window.addEventListener("message", messageHandler)
 			return () => window.removeEventListener("message", messageHandler)
-		}, [setInputValue, searchRequestId, inputValue])
+		}, [setInputValue, searchRequestId, normalizedInputValue])
 
 		const [isDraggingOver, setIsDraggingOver] = useState(false)
 		const [textAreaBaseHeight, setTextAreaBaseHeight] = useState<number | undefined>(undefined)
@@ -228,7 +233,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 			clineMessages,
 			taskHistory,
 			cwd,
-			inputValue,
+			inputValue: normalizedInputValue,
 			setInputValue,
 		})
 
@@ -244,22 +249,22 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 		}, [selectedType, searchQuery])
 
 		const handleEnhancePrompt = useCallback(() => {
-			const trimmedInput = inputValue.trim()
+			const trimmedInput = normalizedInputValue.trim()
 
 			if (trimmedInput) {
 				setIsEnhancingPrompt(true)
 				vscode.postMessage({ type: "enhancePrompt" as const, text: trimmedInput })
 			} else {
 				setInputValue(t("chat:enhancePromptDescription"))
 			}
-		}, [inputValue, setInputValue, t])
+		}, [normalizedInputValue, setInputValue, t])
 
 		const allModes = useMemo(() => getAllModes(customModes), [customModes])
 
 		// Memoized check for whether the input has content (text or images)
 		const hasInputContent = useMemo(() => {
-			return inputValue.trim().length > 0 || selectedImages.length > 0
-		}, [inputValue, selectedImages])
+			return normalizedInputValue.trim().length > 0 || selectedImages.length > 0
+		}, [normalizedInputValue, selectedImages])
 
 		// Compute the key combination text for the send button tooltip based on enterBehavior
 		const sendKeyCombination = useMemo(() => {
@@ -508,8 +513,8 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 				}
 
 				if (event.key === "Backspace" && !isComposing) {
-					const charBeforeCursor = inputValue[cursorPosition - 1]
-					const charAfterCursor = inputValue[cursorPosition + 1]
+					const charBeforeCursor = normalizedInputValue[cursorPosition - 1]
+					const charAfterCursor = normalizedInputValue[cursorPosition + 1]
 
 					const charBeforeIsWhitespace =
 						charBeforeCursor === " " || charBeforeCursor === "\n" || charBeforeCursor === "\r\n"
@@ -521,7 +526,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 					if (
 						charBeforeIsWhitespace &&
 						// "$" is added to ensure the match occurs at the end of the string.
-						inputValue.slice(0, cursorPosition - 1).match(new RegExp(mentionRegex.source + "$"))
+						normalizedInputValue.slice(0, cursorPosition - 1).match(new RegExp(mentionRegex.source + "$"))
 					) {
 						const newCursorPosition = cursorPosition - 1
 						// If mention is followed by another word, then instead
@@ -536,9 +541,9 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 						setCursorPosition(newCursorPosition)
 						setJustDeletedSpaceAfterMention(true)
 					} else if (justDeletedSpaceAfterMention) {
-						const { newText, newPosition } = removeMention(inputValue, cursorPosition)
+						const { newText, newPosition } = removeMention(normalizedInputValue, cursorPosition)
 
-						if (newText !== inputValue) {
+						if (newText !== normalizedInputValue) {
 							event.preventDefault()
 							setInputValue(newText)
 							setIntendedCursorPosition(newPosition) // Store the new cursor position in state
@@ -558,7 +563,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 				selectedMenuIndex,
 				handleMentionSelect,
 				selectedType,
-				inputValue,
+				normalizedInputValue,
 				cursorPosition,
 				setInputValue,
 				justDeletedSpaceAfterMention,
@@ -577,7 +582,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 				textAreaRef.current.setSelectionRange(intendedCursorPosition, intendedCursorPosition)
 				setIntendedCursorPosition(null) // Reset the state.
 			}
-		}, [inputValue, intendedCursorPosition])
+		}, [normalizedInputValue, intendedCursorPosition])
 
 		// Ref to store the search timeout.
 		const searchTimeoutRef = useRef<NodeJS.Timeout | null>(null)
@@ -677,7 +682,10 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 					e.preventDefault()
 					const trimmedUrl = pastedText.trim()
 					const newValue =
-						inputValue.slice(0, cursorPosition) + trimmedUrl + " " + inputValue.slice(cursorPosition)
+						normalizedInputValue.slice(0, cursorPosition) +
+						trimmedUrl +
+						" " +
+						normalizedInputValue.slice(cursorPosition)
 					setInputValue(newValue)
 					const newCursorPosition = cursorPosition + trimmedUrl.length + 1
 					setCursorPosition(newCursorPosition)
@@ -740,7 +748,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 					}
 				}
 			},
-			[shouldDisableImages, setSelectedImages, cursorPosition, setInputValue, inputValue, t],
+			[shouldDisableImages, setSelectedImages, cursorPosition, setInputValue, normalizedInputValue, t],
 		)
 
 		const handleMenuMouseDown = useCallback(() => {
@@ -790,7 +798,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 
 		useLayoutEffect(() => {
 			updateHighlights()
-		}, [inputValue, updateHighlights])
+		}, [normalizedInputValue, updateHighlights])
 
 		const updateCursorPosition = useCallback(() => {
 			if (textAreaRef.current) {
@@ -822,7 +830,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 
 					if (lines.length > 0) {
 						// Process each line as a separate file path
-						let newValue = inputValue.slice(0, cursorPosition)
+						let newValue = normalizedInputValue.slice(0, cursorPosition)
 						let totalLength = 0
 
 						// Using a standard for loop instead of forEach for potential performance gains.
@@ -841,7 +849,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 						}
 
 						// Add space after the last mention and append the rest of the input
-						newValue += " " + inputValue.slice(cursorPosition)
+						newValue += " " + normalizedInputValue.slice(cursorPosition)
 						totalLength += 1
 
 						setInputValue(newValue)
@@ -902,7 +910,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 			[
 				cursorPosition,
 				cwd,
-				inputValue,
+				normalizedInputValue,
 				setInputValue,
 				setCursorPosition,
 				setIntendedCursorPosition,
@@ -995,7 +1003,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 								<ContextMenu
 									onSelect={handleMentionSelect}
 									searchQuery={searchQuery}
-									inputValue={inputValue}
+									inputValue={normalizedInputValue}
 									onMouseDown={handleMenuMouseDown}
 									selectedIndex={selectedMenuIndex}
 									setSelectedIndex={setSelectedMenuIndex}
@@ -1058,7 +1066,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 									}
 									textAreaRef.current = el
 								}}
-								value={inputValue}
+								value={normalizedInputValue}
 								onChange={(e) => {
 									handleInputChange(e)
 									updateHighlights()
@@ -1264,7 +1272,7 @@ export const ChatTextArea = forwardRef<HTMLTextAreaElement, ChatTextAreaProps>(
 								</StandardTooltip>
 							</div>
 
-							{!inputValue && (
+							{!normalizedInputValue && (
 								<div
 									className={cn(
 										"absolute left-2 z-30 flex items-center h-8 font-vscode-font-family text-vscode-editor-font-size leading-vscode-editor-line-height",

webview-ui/src/components/chat/ChatView.tsx

@@ -1431,6 +1431,14 @@ const ChatViewComponent: React.ForwardRefRenderFunction<ChatViewRef, ChatViewPro
 
 	const handleSuggestionClickInRow = useCallback(
 		(suggestion: SuggestionItem, event?: React.MouseEvent) => {
+			// The model may emit suggestions with missing or blank answers (issue #1226).
+			// Ignore them instead of pushing an undefined value into the input, which
+			// would crash the text area (inputValue.trim on undefined).
+			const answer = typeof suggestion?.answer === "string" ? suggestion.answer.trim() : ""
+			if (!answer) {
+				return
+			}
+
 			// Mark that user has responded if this is a manual click (not auto-approval)
 			if (event) {
 				userRespondedRef.current = true
@@ -1455,13 +1463,13 @@ const ChatViewComponent: React.ForwardRefRenderFunction<ChatViewRef, ChatViewPro
 			if (event?.shiftKey) {
 				// Always append to existing text, don't overwrite
 				setInputValue((currentValue: string) => {
-					return currentValue !== "" ? `${currentValue} \n${suggestion.answer}` : suggestion.answer
+					return currentValue !== "" ? `${currentValue} \n${answer}` : answer
 				})
 			} else {
 				// Don't clear the input value when sending a follow-up choice
 				// The message should be sent but the text area should preserve what the user typed
 				const preservedInput = inputValueRef.current
-				handleSendMessage(suggestion.answer, [])
+				handleSendMessage(answer, [])
 				// Restore the input value after sending
 				setInputValue(preservedInput)
 			}