feat: allow generator expressions in highlevel operations that accept iterable of arrays as input

[ikrommyd]

Closes #3937

[github-actions]

The documentation preview is ready to be viewed at http://preview.awkward-array.org.s3-website.us-east-1.amazonaws.com/PR3938

[ianna]

@ikrommyd - great, thanks. Would it make sense to expand the tests to include axis parameter, deeply nested structures, record arrays, negative tests (e.g. with an invalid axis or bad nested structure), also type/shape checks?

[ikrommyd]

Yeah I can add a little bit more testing although it would be over-testing mostly cause the only thing we want to test really is that generator expressions just behave the same as other iterables like lists or tuples (assuming axes and nestedness is tested in other tests).

[ianna]

Yeah I can add a little bit more testing although it would be over-testing mostly cause the only thing we want to test really is that generator expressions just behave the same as other iterables like lists or tuples (assuming axes and nestedness is tested in other tests).

I don't know if these are tested for generators... you might be right

[ikrommyd]

I added a little more thorough testing. Should be good from my side now

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 85.28%. Comparing base (7499387) to head (30199d8).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

Files with missing lines	Coverage Δ
src/awkward/operations/ak_argcartesian.py	83.33% <100.00%> (+0.72%)	⬆️
src/awkward/operations/ak_cartesian.py	92.24% <100.00%> (+0.06%)	⬆️
src/awkward/operations/ak_concatenate.py	85.91% <100.00%> (+0.04%)	⬆️
src/awkward/operations/ak_zip.py	96.07% <100.00%> (+0.07%)	⬆️
src/awkward/operations/ak_zip_no_broadcast.py	86.44% <100.00%> (+0.23%)	⬆️

... and 6 files with indirect coverage changes

[ianna]

@ikrommyd - looks great! Thanks for addressing comments.