docs(python): Clarify explanation and examples for .eq_missing

[bertiewooster]

Fixes #16867 with explanation proposed by @mcrumiller. Provides examples that .eq_missing() will return False whether the number is on the left (the Expr) or right (the other parameter) when the other value is None. For documentation page https://docs.pola.rs/api/python/stable/reference/expressions/api/polars.Expr.eq_missing.html.

[bertiewooster]

The test failure seems unrelated to the change in this PR; the failure is in Run Python tests - async reader

tests/unit/io/test_file_cache.py:54: in test_file_cache_ttl
    assert [x.exists() for x in metadata_file_paths] == [True, False]
E   assert [True, True] == [True, False]

[coastalwhite]

Could you rebase this onto the main branch. I am pretty sure, it will pass the CI if you do that.

[stinodego]

Thanks! Could you also update Series.eq_missing?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.86%. Comparing base (235ebee) to head (dfa4485).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #17003   +/-   ##
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  Coverage   80.86%   80.86%           
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  Files        1455     1455           
  Lines      191086   191093    +7     
  Branches     2723     2724    +1     
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+ Hits       154519   154525    +6     
- Misses      36063    36064    +1     
  Partials      504      504           

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[bertiewooster]

Could you rebase this onto the main branch. I am pretty sure, it will pass the CI if you do that.

That worked. Thanks!

[bertiewooster]

Thanks! Could you also update Series.eq_missing?

@stinodego I'm happy to do, but...

The pages for Series.eq and Series.eq_missing don't seem to exist: stubs exist on the Series page, but they are not hyperlinked (not underlinked in the screenshot below). Also, searching the docs for eq_missing doesn't find a Series method page. In fact, it seems like the entire Operators section for Series does not exist: ge, gt, ne, etc. are also missing. (The links I gave are for the dev docs; same results on the stable and v1 docs.)

So I don't think I'll be able to check the results (a web page built by Sphinx) of updating the Series.eq_missing docstring, correct?

If that's correct, perhaps I should hold off for now and do a separate PR when the Series.eq_missing page exists?

[stinodego]

The pages for Series.eq and Series.eq_missing don't seem to exist

Oops, good catch. I added them :)

[bertiewooster]

Great, the Series Operators pages now exist. And I made the analogous changes to the Series.eq_missing docstring, both description and Examples.

[bertiewooster]

@stinodego Could this PR be merged so the Series Operators section's pages will be added (they're still missing in the 1.0 docs), and .eq_missing will be improved? I addressed your requested changes by updating Series.eq_missing. Thanks!

[DeflateAwning]

What's needed here? The ambiguity solved here came up in a discussion among core maintainers in #18728 again here.

I can try to help with code changes if there's anything remaining here. Otherwise, @mcrumiller or @cmdlineluser, while these discussions are fresh, maybe you can check?