decide on how to handle `empty_like`

Is your feature request related to a problem?

calling np.empty_like seems to be instantiating the whole array.

from xarray.tests import InaccessibleArray
import xarray as xr
import numpy as np

array = InaccessibleArray(np.zeros((3, 3), dtype="uint8"))
da = xr.DataArray(array, dims=["x", "y"])

np.empty_like(da)

Traceback (most recent call last):
  File "/home/mark/t.py", line 8, in <module>
    np.empty_like(da)
  File "/home/mark/mambaforge/envs/dev/lib/python3.9/site-packages/xarray/core/common.py", line 165, in __array__
    return np.asarray(self.values, dtype=dtype)
  File "/home/mark/mambaforge/envs/dev/lib/python3.9/site-packages/xarray/core/dataarray.py", line 732, in values
    return self.variable.values
  File "/home/mark/mambaforge/envs/dev/lib/python3.9/site-packages/xarray/core/variable.py", line 614, in values
    return _as_array_or_item(self._data)
  File "/home/mark/mambaforge/envs/dev/lib/python3.9/site-packages/xarray/core/variable.py", line 314, in _as_array_or_item
    data = np.asarray(data)
  File "/home/mark/mambaforge/envs/dev/lib/python3.9/site-packages/xarray/tests/__init__.py", line 151, in __array__
    raise UnexpectedDataAccess("Tried accessing data")
xarray.tests.UnexpectedDataAccess: Tried accessing data

Describe the solution you'd like

I'm not too sure. This is why I raised this as a "feature" and not a bug.

On one hand, it is pretty hard to "get" the underlying class.

Is it a:

• numpy array
• a lazy thing that looks like a numpy array?
• a dask array when it is dask?

I think that there are also some nuances between:

1. Loading an nc file from a file (where things might be handled by dask even though you don't want them to be)
2. Creating your xarray from in memory.

Describe alternatives you've considered

for now, i'm trying to avoid empty_like or zeros_like.

In general, we haven't seen much benefit from dask and cuda still needs careful memory management.

Additional context

No response

Read xarray/core/common.py, xarray/core/dataarray.py, and xarray/core/variable.py around the traceback, then reproduce the InaccessibleArray example. Determine the intended empty_like behavior for in-memory and lazy arrays; done means the behavior is agreed and covered by regression tests.