What happened:

dask.array.nanmin(np.int_(3)).compute() returns TypeError: len() of unsized object. This still worked in v2021.11.2. Only nanmin and nanmax seem affected, nansum etc still work.

What you expected to happen:

No error.

Minimal Complete Verifiable Example:

import dask.array
arr = dask.array.array([0, 1, 2])
dask.array.nanmin(arr[0]).compute()

# or
dask.array.nanmax(np.int_(3)).compute()

Anything else we need to know?:

xref: pydata/xarray#6016

Environment:

• Dask version: 2021.12.0
• Python version: 3.9
• Operating System: linux
• Install method (conda, pip, source): conda