DOC: unclear kwarg null_counts

[ivanovmg]

Location of the documentation

https://pandas.pydata.org/docs/dev/reference/api/pandas.DataFrame.info.html?highlight=info#pandas.DataFrame.info

Documentation problem

Keyword null_counts from its name may be considered as a need to count null items.
However, the documentation explains that is quite the opposite - count non-null items.
I suggest to rename it with show_counts and maintain the old behavior.

Suggested fix for documentation

Replace null_counts with show_counts.
It will make it more clear what this kwarg means without even the need to read docs.

API

It the suggested rename is implemented, then need to start deprecation of kwarg null_counts.

[MarcoGorelli]

I agree that it's a bit of a misnomer, but wouldn't renaming potentially break people's code?

[ivanovmg]

I suggest smooth transition to the new kwarg via the deprecation process, so that nobody's code gets broken right away.
We can start with throwing warnings that the old kwarg is deprecated and in version X.X will be removed.

[MarcoGorelli]

Might be worth it actually - I think people are only likely to use .info in an interactive session, rather than as part of production code, so perhaps it is worth going through the deprecation process to make this argument clearer