also test macos

[Mic92]

No description provided.

[bbenne10]

I believe we could start testing on MacOS with #598 merged, since we don't explicitly gc anymore?

[Mic92]

We could also move tests to nix if we use toybox and bare derivations to allow building nix-shells in the nix sandbox.

[Mic92]

Looks like macOS is still broken.

[bbenne10]

I just looked at these failures and I think this is a weird difference in behavior that I don't fully understand right now. It's telling us that the direnvrc inside the testenv is not approved, but it absolutely should be, since the function I call immediately prior to this (write_envrc) immediately approves the contents after writing the envrc...

[bbenne10]

Updated to latest master to see if the changes made in the disallow_fallback branch help resolve the problems we're seeing here.

[bbenne10]

About what I expected: Tests still failing and telling us very little other than the envrc file is not approved. I might have to pull out my macbook sometime soon to figure this one out.