Pandas ENH: Infer enums as categories

Feature Type

• [ ] Adding new functionality to pandas

• [x] Changing existing functionality in pandas

• [ ] Removing existing functionality in pandas

Problem Description

I wish enum types like StrEnum would be recognized as Categories by the type guessing functions, e.g. infer_objects or convert_dtypes as there is more information there then python[string]

Feature Description

With a frame as follows

from enum import StrEnum
import pandas as pd

class MyEnum(StrEnum):
    A="a"
    B="b"
    C="c"


df=pd.json_normalize([{"k": x } for x in MyEnum if x !=MyEnum.C]).infer_objects()

df.dtypes should return

k    category
dtype: object

instead of

k    object
dtype: object

and the category should contain all enum values as they are used for plots.

Alternative Solutions

Manually specify a category for every enum-based column

Additional Context

Maybe the EnumCategories types could even be global like polars so merging on these categories is quicker.

Comment From: jbrockmendel

I’d be fine with this if you’d like to open a PR. I think I’ve seen similar issues before.