einvoice/readme.howtofixtests.md

How to Fix Tests in the einvoice Library

Important: You CAN Modify the Library Code!

When tests fail, the goal is to fix the root causes in the einvoice library itself, not just adjust test expectations.

Key Points:

1. Tests reveal bugs - If a test shows that UTF-8 characters aren't preserved, that's a bug in the library
2. Fix the library - Modify the code in ts/ to make the tests pass
3. Maintain spec compliance - The goal is to be as spec-compliant as possible
4. Don't lower expectations - Don't make tests pass by accepting broken behavior

Common Issues to Fix:

1. UTF-8 Character Preservation

   • Special characters should be preserved in all fields
   • Invoice IDs with special characters should work
   • Subject and notes fields should maintain their content

2. Round-trip Conversion

   • Data exported to XML and imported back should remain the same
   • All fields should be preserved during import/export

3. Character Encoding

   • XML should properly handle all UTF-8 characters
   • Special XML characters (&, <, >, ", ') should be properly escaped
   • Unicode characters should be preserved, not converted to entities

Process:

1. Run the failing test
2. Identify what the library is doing wrong
3. Fix the library code in ts/
4. Verify the test now passes
5. Ensure no other tests break

Remember: The tests are there to improve the einvoice library!