Adapt storage tests for changes in fsspec (#1819) (#1679)

[AdamWill]

This is adapted from the fixes that were rolled into https://github.com/zarr-developers/zarr-python/pull/1785 for the v3 branch.

TODO:

• [ ] GitHub Actions have all passed
• [ ] Test coverage is 100% (Codecov passes)

Deleted TODO items are not applicable as this changes no code, only tests.

[AdamWill]

On v3 the check in test_hierarchy was commented out entirely, but that seems excessive to me. The comment # no exception raised if path does not exist or is leaf indicates the primary point of these checks is to make sure the listdir calls run without causing an assertion, and we can still do that, and check that the result is one of the two we know are possible.

[dstansby]

Thanks for this! To get the tests passing, I think the version of fsspec in requirements_dev_optional.txt will need increasing to a version that's compatible with the new tests.

[AdamWill]

ugh, it's been a while, but I think the change is supposed to work with both old and new fsspec? I'll try and find a minute to remember it...

[jhamman]

I'm going to close this as stale. Folks should feel free to reopen if there is interest in continuing this work.

[AdamWill]

yeah, looking at it again, this is intended to work both ways.

[AdamWill]

eh, but looking at the test results, it didn't. not sure why not, i'd have to remember all this stuff again. sigh.