nix copy --from file:// requires unexpected flake in cwd

[tmplt]

Describe the bug

nix copy --from file:// on a directory created by nix copy --to file:// fails because it cannot find a flake.nix in the current working directory, or above.

Steps To Reproduce

$ pwd
/home/tmplt
$ nix copy --to file:///tmp/nix-copy-hello nixpkgs#hello
$ nix copy --from file:///tmp/nix-copy-hello 
path '/home/tmplt' does not contain a 'flake.nix', searching up
error: could not find a flake.nix file

Expected behavior

I expect the nix copy --from command to import the binary cache to the system's (but effectively being noop because the derivation already exists there?).

nix-env --version output

nix-env (Nix) 2.18.1

Additional context

I have nix-command flakes enabled globally, but overriding using --experimental-features nix-command yields the same error.

Priorities

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[thufschmitt]

nix copy copies the store paths specified on the command-line (defaulting to the flake in the current directory like the rest of the command-line).

If you want to copy the whole store, you can use --all (I hope, if it doesn't work, that is a bug).

Do you think the description in the manual needs to be altered to make this more explicit? If so feel free to open a PR to fix it

[tmplt]

Thanks, I wasn't aware of --all. It's a bit too hidden and abstracted in my opinion: #10227.