[bug] Selecting blank ask followup question causes crash

[sameemqureshi]

Problem (one or two sentences)

Empty Messaes When a General Message Like Hi is Given .

Context (who is affected and when)

Since , This is Empty , Clicking on it Results in Crashing Roo . his is empty

Reproduction steps

Configure Google Gemini with gemini-flash-latest model , and Give a Simple Hi Message .

Expected result

The Follow Up Responses Must not Be Blank .

Actual result

Blank Responses Resulting in Roo Code Crash .

Variations tried (optional)

This Issue is Only Specific to gemini-flash-latest Model and isnt Reproducible for Other models .

App Version

3.39.3

API Provider (optional)

Google Gemini

Model Used (optional)

gemini-flash-latest

Roo Code Task Links (optional)

No response

Relevant logs or errors (optional)

Error Stack : 
TypeError: Cannot read properties of undefined (reading 'trim')
    at inputValue.trim (../../../../webview-ui/src/components/chat/ChatTextArea.tsx:259:21)
    at ti (../../../../node_modules/.pnpm/react-dom@18.3.1_react@18.3.1/node_modules/react-dom/cjs/react-dom.production.min.js:172:118)
    at useMemo (../../../../node_modules/.pnpm/react@18.3.1/node_modules/react/cjs/react.production.min.js:26:47)
    at inputValue.trim (../../../../webview-ui/src/components/chat/ChatTextArea.tsx:258:26)
    at Nh (../../../../node_modules/.pnpm/react-dom@18.3.1_react@18.3.1/node_modules/react-dom/cjs/react-dom.production.min.js:160:136)
    at Yi (../../../../node_modules/.pnpm/react-dom@18.3.1_react@18.3.1/node_modules/react-dom/cjs/react-dom.production.min.js:192:56)
    at f,b.memoizedState=f,b.flags&256){e=Ji(Error(p(423)),b);b=lj (../../../../node_modules/.pnpm/react-dom@18.3.1_react@18.3.1/node_modules/react-dom/cjs/react-dom.production.min.js:293:274)
    at tj (../../../../node_modules/.pnpm/react-dom@18.3.1_react@18.3.1/node_modules/react-dom/cjs/react-dom.production.min.js:279:388)
    at tj (../../../../node_modules/.pnpm/react-dom@18.3.1_react@18.3.1/node_modules/react-dom/cjs/react-dom.production.min.js:279:319)
    at tj (../../../../node_modules/.pnpm/react-dom@18.3.1_react@18.3.1/node_modules/react-dom/cjs/react-dom.production.min.js:279:179)


Component Stack :
    at https://file+.vscode-resource.vscode-cdn.net/Users/mqureshi/.vscode/extensions/rooveterinaryinc.roo-cline-3.39.3/webview-ui/build/assets/index.js:668:194375
    at div
at w7 (../../../../webview-ui/src/components/chat/ChatView.tsx:66:3)
at IG (../../../../webview-ui/src/App.tsx:69:5)
at p (../../../../node_modules/.pnpm/@radix-ui+react-context@1.1.2_@types+react@18.3.23_react@18.3.1/node_modules/@radix-ui/react-context/dist/index.mjs:27:14)
at X6e (../../../../node_modules/.pnpm/@radix-ui+react-tooltip@1.2.6_@types+react-dom@18.3.7_@types+react@18.3.23__@types+reac_99504aa956c623e0884a4e3cb215669a/node_modules/@radix-ui/react-tooltip/dist/index.mjs:29:4)
at sRt (../../../../webview-ui/src/components/ui/tooltip.tsx:8:27)
at iC (../../../../node_modules/.pnpm/@tanstack+react-query@5.76.1_react@18.3.1/node_modules/@tanstack/react-query/build/modern/QueryClientProvider.js:20:2)
at YPt (../../../../webview-ui/src/i18n/TranslationContext.tsx:16:73)
at ZPt (../../../../webview-ui/src/context/ExtensionStateContext.tsx:194:89)
at yPt (../../../../webview-ui/src/components/ErrorBoundary.tsx:18:2)
at i (../../../../node_modules/.pnpm/react-i18next@15.5.1_i18next@25.2.1_typescript@5.8.3__react-dom@18.3.1_react@18.3.1__react@18.3.1_typescript@5.8.3/node_modules/react-i18next/dist/es/withTranslation.js:6:4)
    at EG

[roomote]

I have analyzed this issue and here is my proposed implementation plan:

Root Cause:
The error TypeError: Cannot read properties of undefined (reading 'trim') occurs at ChatTextArea.tsx:259 when inputValue is undefined. This happens when the Gemini model returns an empty/blank response, causing the parent component to pass undefined instead of an empty string to the inputValue prop.

Proposed Fix:
Add defensive null/undefined checks in ChatTextArea.tsx where inputValue is used as a string:

1. Line 259 (the crashing line in hasInputContent memo):

   return (inputValue ?? "").trim().length > 0 || selectedImages.length > 0

2. Line 245 (in handleEnhancePrompt):

   const trimmedInput = (inputValue ?? "").trim()

3. Line 678 (in handlePaste):

   inputValue.slice(0, cursorPosition) // Already guarded by if (textAreaRef.current)

   These usages are protected by the check at line 666 (const pastedText = e.clipboardData.getData("text")), but for extra safety we could add null coalescing.

4. Line 823 (in handleDrop):

   let newValue = (inputValue ?? "").slice(0, cursorPosition)

This approach ensures the component gracefully handles undefined or null values by defaulting to an empty string, preventing the crash.

Please mention @roomote in a comment saying that you approve this plan, and I will proceed with the implementation.

[sameemqureshi]

@roomote .
Sounds Good

[roomote]

Thanks for the approval! I'll proceed with implementing the fix now. I'll add defensive null/undefined checks to ChatTextArea.tsx to handle cases where inputValue is undefined. I'll open a PR shortly with the changes.

[roomote]

Opened a PR with my attempt at addressing this: #10632

The fix adds defensive null/undefined checks to ChatTextArea.tsx to gracefully handle cases where inputValue is undefined (as happens when Gemini returns blank responses). Feedback welcome!