• closes BUG: infer_dtype_from_scalar infers nanosecond dtype for second input #51196 (Replace xxxx with the issue number)
• Tests added and passed if fixing a bug or adding a new feature
• All code checks passed.
• Added type annotations to new arguments/methods/functions.
• Added an entry in the latest doc/source/whatsnew/vX.X.X.rst file if fixing a bug or adding a new feature.

Needs whatsnew and targeted tests, opening to see if there are opinions about doing this as a bugfix or waiting to do it as an API change in 3.0

This pull request is stale because it has been open for thirty days with no activity. Please update and respond to this comment if you're still interested in working on this.

@MarcoGorelli thoughts on if/how this is worth pursuing?

sorry, missed this. I'd have thought this was fine as a bug fix - I'm at jupytercon next week though so may be a bit slow to review, but will take a look when I get a chance

nice! just got some minor comments

[MarcoGorelli]

this risks staying here forever, could you add strict=True please, so that when it's fixed we remember to remove this?

[jbrockmendel]

is strict=True no longer the default? if so, will update. (also if so: yikes)

[MarcoGorelli]

nvm, ignore me, it's configured to be the default

xfail_strict = true

Changes look good to me, I think it'd be OK to get this into 2.1 as it'd be a bug fix

do you want to add a whatsnew note?

🤔 not sure if this might be related

FAILED pandas/tests/frame/methods/test_reindex.py::TestDataFrameSelectReindex::test_reindex_tzaware_fill_value - ValueError: Unexpected value for 'dtype': 'int32'. Must be 'datetime64[s]', 'datetime64[ms]', 'datetime64[us]', 'datetime64[ns]' or DatetimeTZDtype'.

Looks good to me

@mroeschke any comments, or good to go?

Thanks @jbrockmendel