[backport 2.3.x] API: ignore empty range/object dtype in Index setop operations (string dtype compat) (#60797)

[jorisvandenbossche]

(cherry picked from commit ee06e71)

Backport of #60797

[github-actions]

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[datapythonista]

I guess this is not happening. Feel free to reopen if needed.

[jorisvandenbossche]

@mroeschke FWIW best not to remove milestones from backport PRs, because then we will certainly loose track of them .. (or in general please add a comment when doing so, such that it generates a notification, because unfortunately github makes milestone changes silent)

I of course should have updated this a while ago, but ideally this still goes into 2.3.x (assuming there might be some more bugfix release)

[mroeschke]

Ah sorry about that @jorisvandenbossche. Thanks for the reminder

[jorisvandenbossche]

There are a bunch of failures in the expression tests, eg pandas/tests/test_expressions.py::TestExpressions::test_run_binary[eq-True-_integer_integers], but that doesn't seem related (and also seeing it on another backport PR)

[jorisvandenbossche]

There are a bunch of failures in the expression tests, eg pandas/tests/test_expressions.py::TestExpressions::test_run_binary[eq-True-_integer_integers], but that doesn't seem related (and also seeing it on another backport PR)

Handling that in #61638