Problem

Syntax errors in definePage() calls would crash the Vite development server, making it impossible to continue development when there were JavaScript syntax issues in the page definition. This created a poor developer experience where a simple typo could bring down the entire dev server.

<script setup>
// This would crash the server
definePage({
  name: 'test',,  // Extra comma - syntax error
  path: '/test'
})
</script>

Solution

Enhanced error handling throughout the definePage processing pipeline to gracefully handle syntax errors and parsing failures:

Key Changes

1. Added comprehensive try-catch blocks in definePageTransform() and extractDefinePageNameAndPath() functions to catch any parsing or processing errors

2. Enhanced getCodeAst() function with error handling around Babel AST parsing to prevent syntax errors from propagating

3. Changed error behavior from throwing SyntaxErrors to logging warnings and returning safe fallback values:

   • When extracting definePage: returns 'export default {}'
   • When removing definePage from source: returns undefined (no transform)

4. Improved developer feedback by replacing crashes with helpful warning messages that identify the problematic file

Testing

Added comprehensive test coverage for various syntax error scenarios:

• Extra commas in object literals
• Missing commas between properties
• Completely malformed JavaScript
• Unclosed brackets
• Invalid scope references

Impact

• ✅ Vite server no longer crashes on definePage syntax errors
• ✅ Development can continue with broken definePage calls (they're simply ignored)
• ✅ Clear warning messages help developers identify and fix issues
• ✅ Maintains backward compatibility for all valid definePage usage
• ✅ No performance impact on normal operation

The fix ensures a more robust development experience while maintaining all existing functionality for properly formatted definePage() calls.

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