The source map parser was failing with "Invalid token: sourceCode must be an array" error when parsing JavaScript error stack traces. This was preventing users from successfully mapping minified stack traces back to their original source code locations.

Root Cause

The issue was a naming convention mismatch between the WebAssembly module response and the TypeScript interface validation:

WebAssembly Module Response (snake_case):

{
  "line": 9,
  "column": 10,
  "source_code": [
    {
      "line": 8,
      "is_stack_line": false,
      "raw": "  useEffect(() => {"
    }
  ],
  "src": "../../src/App.jsx"
}

TypeScript Interface (camelCase):

interface Token {
  sourceCode: SourceCode[]; // Expected camelCase, got snake_case
}

interface SourceCode {
  isStackLine: boolean; // Expected camelCase, got snake_case
}

Solution

Added a transformToken() method that converts the WebAssembly response format to match the TypeScript interfaces:

• source_code → sourceCode
• is_stack_line → isStackLine

This transformation happens before token validation, ensuring the structure matches the expected interface while maintaining type safety.

Testing

Added comprehensive tests that verify all 10 stack trace entries from the original issue report now parse successfully, correctly mapping to their source locations (e.g., React components, React DOM internals, scheduler functions).

The fix maintains backward compatibility and doesn't affect any existing functionality.

Fixes #21.

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