fix: proper retrieval of answers for batch eval

[vblagoje]

Related Issues

• fixes Pipeline eval breaks when node has empty answers list in Tutorial 15 TableQA #3159

Proposed Changes:

Improper list access. Fixed the list access

How did you test it?

TODO

Notes for the reviewer

Please review carefully and run the previous failing tests

Checklist

• I have read the contributors guidelines and the code of conduct
• I have updated the related issue with new insights and changes
• I added tests that demonstrate the correct behavior of the change
• I've used the conventional commit convention for my PR title
• I documented my code
• I ran pre-commit hooks and fixed any issue

[vblagoje]

@bglearning and @masci let me know what you guys think. Would you also please run the existing manual tests that fail?

[masci]

I think that piece of code should be refactored a bit but for the scope of this PR it's better to keep the diff small, so it's 👍 from my side.

I tested your branch on Tutorial 15 in colab and it works.

[bglearning]

@vblagoje Just realized the error that Miriam had was from a different line which has a similar faulty pattern.

Specifically this one base.py#L1610

if documents is not None:
    if isinstance(documents[i], list): # Index out of range with this
        documents = documents[i]
    if len(documents) == 0:
        ...

Maybe best to also update that line too.

[vblagoje]

@bglearning added your fix, please verify. If all is good, please integrate as well.

[bglearning]

LGTM 👍