Nix's test for recursive builds passed, even though support for recursive Nix was functionally deleted

[grahamc]

In #4030, commit ca30abb deleted RestrictedStore's addToStoreFromDump implementation which effectively deleted support for recursive-nix. That commit was reverted and the behavior restored in #4209. However, throughout that whole time the test for recursive-nix never failed: https://github.com/NixOS/nix/blob/master/tests/recursive.sh

An example use case of recursive Nix is https://github.com/grahamc/netboot.nix/ and https://github.com/grahamc/netboot.nix/blob/master/size-test/build.sh and running this build.sh on a machine configured with recursive-nix would fail with operation 'addToStoreFromDump' is not supported by store 'local'.

Ideally, we'd revert the patch which added it, edited the test to fail, and then unrevert the patch.

[stale]

I marked this as stale due to inactivity. → More info