-rm -rf "$repo_dir" "$conf"
-
-expected_env_command_RE='^nix-env --profile /nix/var/nix/profiles/per-user/[^/]+/channels --show-trace --file '\''<nix/unpack-channel.nix>'\'' --install --from-expression '\''f: f \{ name = "(repo-[0-9]{10}-[0-9a-f]{11})"; channelName = "foo"; src = builtins.storePath "/nix/store/.{32}-\1.tar.xz"; \}'\''$'
+expected_env_command_RE='^nix-env --profile /nix/var/nix/profiles/per-user/[^/]+/channels --show-trace --file '\''<nix/unpack-channel.nix>'\'' --install --from-expression '\''f: f \{ name = "(repo-[0-9]{10}-[0-9a-f]{11})"; channelName = "foo"; src = builtins.storePath "'"$NIX_STORE_DIR"'/.{32}-\1.tar.xz"; \}'\''$'