Add simple check for meta-indicator value type

[danielhuppmann]

This is an alternative to #257, raising a clear error message when meta-indicator values of an unsupported type are added instead of (trying to) casting everything unexpected to string.

Closes #256

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.7%. Comparing base (9e97d27) to head (f2be6f9).

Additional details and impacted files

@@          Coverage Diff          @@
##            main    #258   +/-   ##
=====================================
  Coverage   96.7%   96.7%           
=====================================
  Files        221     221           
  Lines       9841    9853   +12     
=====================================
+ Hits        9520    9532   +12     
  Misses       321     321           

Files with missing lines	Coverage Δ
ixmp4/core/meta.py	98.6% <100.0%> (+<0.1%)	⬆️
ixmp4/data/meta/type.py	100.0% <100.0%> (ø)

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[danielhuppmann]

I give up, I don't know which ruff version to use to make the linter pass...

[meksor]

The version should not matter or the version in the poetry.lock file should work.
At the bottom of the CI job it says:

Would reformat: tests/core/test_meta.py
1 file would be reformatted, 319 files already formatted

Did you try: ruff format tests/core/test_meta.py ?

Edit: My IDE also sorts imports for me which you may be able to achieve using :
ruff check --select I --fix

[danielhuppmann]

Did you try: ruff format tests/core/test_meta.py ?

Of course, and I tried it with both 0.15.12 (per poetry.lock) and 0.15.20 (latest) - locally, all my files are fine...

[meksor]

My IDE also sorts imports for me which you may be able to achieve using :
ruff check --select I --fix

[danielhuppmann]

[meksor]

I cleared the cached virtualenv using the github cli and restarted the Code Quality job.
Sometimes this cache bugs out and generates lots of errors like before, not sure why.
Anyway, now we can also see two mypy errors

tests/core/test_meta.py:55: error: Dict entry 1 has incompatible type "str": "Timestamp"; expected "str": "float | int | str | generic[Any] | None"  [dict-item]
tests/core/test_meta.py:59: error: Incompatible types in assignment (expression has type "Timestamp", target has type "bool | float | int | str | generic[Any] | None")  [assignment]

[meksor]

Wow, thats annoying...
I am not sure how exactly this pre-commit thing works since fridolin set it up, but if it really is a version mismatch (pre-commit is a few versions behind) then you can try changing .pre-commit-config.yaml line 9 to rev: v0.15.12. Maybe I was too confident in ruff backwards compatibility.

[meksor]

#259