I'm not sure we should do this, for a couple of reasons:

• Channels are basically deprecated, so it's probably better not to change their behaviour at this point.
• It could be confusing that nix-channel silently merges different channel lists. (Cf nix flake list, which shows you whether a flake comes from the global, local or user registries.)
• If I read this correctly, it causes commands like nix-channel --add to merge the contents of the user and root channels and rewrite both to have the same contents. That doesn't seem right.

Thanks for the comments. My method is indeed ad hoc.

Only when running by the root user, it writes the channel information of the root user to /nix/store/profiles/per-user/root/nix-channels. This way ordinary users can obtain the channel information of root. The channel information of ordinary users are not written to /nix/store/profiles/per-user/root/nix-channels.

Now that channels are being deprecated, feel free to close this PR. Or if improvement on this commit is desirable, I can add a --root flag to the list operation.

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