GH1383 Add support for creating Series/Index with dtype='category'

[loicdiridollou]

• Closes Index([1], dtype="category") and Series([1], dtype="category") are mistyped #1383
• Tests added: Please use assert_type() to assert the type of any return value

[cmp0xff]

Thank you for the proposal, it looks good to me.

• In tests/series/test_series.py, there are two commented-out lines containing pd.Series[Categorical] (L2917) and pd.Series[category] (L2480), respectively. Could you try to uncomment them and make them work?
• Series[category] is something that does not really exist in the stubs before. @Dr-Irv could you confirm the idea?

[loicdiridollou]

I tried uncommenting the lines and it is raising many errors, I have not thing examples of Series[category] in the code yet.

[Dr-Irv]

Thank you for the proposal, it looks good to me.

• In tests/series/test_series.py, there are two commented-out lines containing pd.Series[Categorical] (L2917) and pd.Series[category] (L2480), respectively. Could you try to uncomment them and make them work?
• Series[category] is something that does not really exist in the stubs before. @Dr-Irv could you confirm the idea?

I think those have been commented out since they were first created. I think they can be uncommented, but they should be using Series[pd.CategoricalDtype] not Series[category] or Series[Categorical]

[cmp0xff]

• Could you merge main into your branch? Resolving conflicts should be easy.
• If you haven't, could you try the idea in #1391 (comment), namely changing to Series[CategoricalDtype]?
• Otherwise it looks good to me, now that the idea of having Series[CategoricalDtype] has also been approved.

[loicdiridollou]

s.astype("dictionary[pyarrow]") is Unknown, not sure if we have the correct overload for it.
Also when I try to do it at run time I get a TypeError so wondering what is the goal of having that only for type checking and not run time. Open to suggestions

[cmp0xff]

s.astype("dictionary[pyarrow]") is Unknown, not sure if we have the correct overload for it. Also when I try to do it at run time I get a TypeError so wondering what is the goal of having that only for type checking and not run time. Open to suggestions

I see, those commented-out tests do not make sense to me, either.

One small thing, otherwise good to go.

[cmp0xff]

Please remove thie comment

[Dr-Irv]

I see, those commented-out tests do not make sense to me, either.

If they don't work at runtime, then let's just delete them and not worry about it.

[cmp0xff]

It looks good to me now, but you have not yet requested me to review again. Would you agree to merge @loicdiridollou ?

[loicdiridollou]

Yes good to merge (I often forgot to rerequest sorry)

[cmp0xff]

Thank you @loicdiridollou! I am getting familiar with the workflow, hopefully I'll be able to do the review better in the future.