Describe the bug

On Nix 2.21 nix edit returns an unhelpful error message when it should just work. It does work with the --impure flag, but I don't see a reason why adding that to the invocation should be necessary when the path to the package definition is derived correctly in printed as part of the error.

The problem does not exist in Nix 2.18.

Steps To Reproduce

> nix edit nixpkgs#nix
error: cannot open '/nix/store/k5l01g2zwhysjyl5zjvg5zxnj0lyxpp1-source/pkgs/tools/package-management/nix/default.nix' in an editor because it has no physical path

nix-env --version output

nix-env (Nix) 2.21.0

Priorities

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