Describe the issue:

The Array.copy docs say that .copy() is a no-op. However, if you actually do a copy a task is added to the graph and the .name of the original and new arrays are not equal.

https://docs.dask.org/en/stable/generated/dask.array.Array.copy.html

See the example below.

Minimal Complete Verifiable Example:

import dask.array as da
a = da.zeros(5)
b = a.copy()

Anything else we need to know?:

In the pyresample library we have custom objects that can contain dask arrays. In the __eq__ of these methods we do a shortcut to avoid having to compute a == b by doing a.name == b.name if the objects are dask arrays. In a lot of our use cases a and b are relatively large arrays that are loaded from files on disk.

This is coming up as a problem for me with xarray where after new behavior to their deep copy logic, dask arrays are now being copied. See pydata/xarray#7111 and pydata/xarray#7089.

Environment:

• Dask version: 2022.9.1
• Python version: 3.10
• Operating System: PopOS
• Install method (conda, pip, source): conda-forge