List the ions of the database utu.spectrum.ions() is given

[roytsmart]

Summary

utu.spectrum.ions(hdf5_dbase_root=...) opened each ion from the database it was given, but listed the ions from fiasco's default database (fiasco.list_ions() with no arguments). An ion that only the given database has was therefore never returned. Its lines were silently missing for any caller that computes lines only for the ions ions() returns.

The ions are now listed from hdf5_dbase_root when it's given, and from fiasco's default database otherwise, as before.

Found by a review of sun-data/solar-dynamics-observatory#28. That PR's generator runs on several CHIANTI databases, and until this is released it guards against the problem itself. CHIANTI 9.0.1 and 11.0.2 list the same 495 ions, so nothing has gone wrong in practice yet.

Test plan

• New test_ions_database replaces fiasco.list_ions with a stand-in and checks that it receives the given database. It fails on main, where the stand-in receives None.
• pytest utu/spectrum/_tests/test_lines.py -k ions passes locally against CHIANTI 11.0.2.
• ruff check . and black --check utu.

🤖 Generated with Claude Code

https://claude.ai/code/session_01TN11CvLpJ9mX44K3MaCyB1

[read-the-docs-community]

Documentation build overview

📚 utu | 🛠️ Build #35063088 | 📁 Comparing 35f1be1 against latest (2f1880b)

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2 files changed

± _autosummary/utu.spectrum.ions.html
± _modules/utu/spectrum/_lines.html

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (2f1880b) to head (35f1be1).

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #13   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files           17        17           
  Lines         1044      1055   +11     
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+ Hits          1044      1055   +11     

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