BUG: ExtensionArray.equals expects ExtensionArray.all to return a numpy.bool_

[xhochy]

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Problem description

The current implementation of ExtensionArray.equals expects that the implementation of ExtensionArray.all always returns a numpy scalar, see

pandas/pandas/core/arrays/base.py

Line 741 in 942beba

return (equal_values | equal_na).all().item()

. If you don't use numpy as the backing memory store, I don't it is reasonable to stick to NumPy scalars here.

Instead, the method should unpack numpy scalars if necessary but passthrough otherwise.

Context: This appeared while running the unit tests with fletcher and pandas' master.