BUG: interpolate gives a TypeError on empty dataframes

[sanderland]

Already fixed in #35543, making an issue for linking/discussion.

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Code Sample, a copy-pastable example

from pandas import DataFrame
DataFrame().interpolate()

"Cannot interpolate with all object-dtype columns "

TypeError: Cannot interpolate with all object-dtype columns in the DataFrame. Try setting at least one column to a numeric dtype.

Problem description

This is a regression, 1.0.5 handles it fine.

The problem appeared due to checking np.all(obj.dtypes == np.dtype(object)) since the all of an empty set is True

Expected Output

Output of pd.show_versions()

pandas : 1.1.0

[simonjayhawkins]

change in behaviour caused by #33084 cc @jbrockmendel

e894809 is the first bad commit
commit e894809
Author: jbrockmendel jbrockmendel@gmail.com
Date: Sun Mar 29 08:16:17 2020 -0700

CLN: de-kludge NDFrame.interpolate (#33084)