4.0 KiB

FIXED: editedCode.trim is not a function

🎯 ROOT CAUSE IDENTIFIED AND FIXED

Problem:

TypeError: editedCode.trim is not a function

Root Cause:

The backend was returning an AgentResult object instead of a string for the code field, causing the frontend to receive a non-string value for editedCode.

🔧 FIXES APPLIED

1. Backend Fix (Primary Issue)

Problem: code_generator_agent() returns AgentResult object, not string Solution: Extract string content from AgentResult

# ❌ BEFORE (Incorrect)
generated_code = code_generator_agent(request.prompt)

# ✅ AFTER (Fixed)
agent_result = code_generator_agent(request.prompt)
generated_code = str(agent_result) if agent_result is not None else ""

Files Fixed:

  • backend/main.py - REST API endpoint /api/generate-code
  • backend/main.py - WebSocket handler for code generation

2. Frontend Defensive Checks

Problem: Frontend didn't validate that editedCode is a string before calling .trim() Solution: Added type checking before string operations

// ❌ BEFORE (Vulnerable)
disabled={!editedCode.trim()}

// ✅ AFTER (Defensive)
disabled={!editedCode || typeof editedCode !== 'string' || !editedCode.trim()}

Files Fixed:

  • frontend/src/App.js - Execute button validation
  • frontend/src/App.js - Interactive execute button validation
  • frontend/src/App.js - Code analysis validation
  • frontend/src/App.js - Line count display validation
  • frontend/src/App.js - WebSocket response handling
  • frontend/src/App.js - File upload handling

3. Data Flow Validation

Problem: No validation of data types in the pipeline Solution: Added type checking at all data entry points

// ✅ WebSocket Response
const code = typeof data.code === 'string' ? data.code : '';

// ✅ API Response  
const code = typeof response.code === 'string' ? response.code : '';

// ✅ File Upload
const codeContent = typeof content === 'string' ? content : '';

📊 VERIFICATION RESULTS

Backend Test:

✅ Agent result type: <class 'strands.agent.agent_result.AgentResult'>
✅ Generated code type: <class 'str'>
✅ Generated code is string: True
✅ Code can be trimmed: "def hello_world():\n    print(\"Hello, World!\")\n\nhel..."
🎉 Backend fix working correctly!

Data Flow:

  1. Agent: Returns AgentResult object
  2. Backend: Converts to string with str(agent_result)
  3. API: Returns string in JSON response
  4. Frontend: Validates string type before .trim()
  5. UI: No more editedCode.trim is not a function error

🎯 IMPACT

Issues Resolved:

  • No more TypeError: editedCode.trim is not a function
  • Robust Error Handling: Frontend handles non-string values gracefully
  • Data Type Safety: All code operations now type-safe
  • Better UX: No more crashes during code generation

Improved Reliability:

  • Backend: Always returns strings for code fields
  • Frontend: Defensive programming prevents type errors
  • WebSocket: Type validation for real-time updates
  • File Upload: Safe handling of file content

🚀 READY FOR USE

The application now:

  • Safely handles all code generation responses
  • Validates data types at every step
  • Prevents crashes from type mismatches
  • Provides better UX with reliable code editing

Test the Fix:

# Start the application
./start.sh

# Generate code - should work without errors
# Try: "Create a function to calculate fibonacci numbers"

SUMMARY

Root Cause: Backend returned AgentResult object instead of string Primary Fix: Extract string content with str(agent_result) Secondary Fix: Add frontend type validation for robustness Result: No more editedCode.trim is not a function errors

The application is now robust and handles all data types safely! 🎉