Activation scripts!

[crabdancing]

It would be great to add Nushell tools for system activation scripts! :)

[MilesCranmer]

I found https://github.com/MercuryTechnologies/nix-your-shell

[MilesCranmer]

Here's a translation of the default bash activation (with bash versions copied in to help out copilot)

use std

let env_cols = ($env | columns)
# if [ -n "$HOME" ] && [ -n "$USER" ]; then
if ("HOME" in $env_cols) and ("USER" in $env_cols) {
#     # Set up the per-user profile.
#     NIX_LINK="$HOME/.nix-profile"
    let NIX_LINK = $"($env.HOME)/.nix-profile"
    let NIX_LINK_NEW = ""
#     if [ -n "${XDG_STATE_HOME-}" ]; then
    if "XDG_STATE_HOME" in $env_cols {
#     else
    } else {
#         NIX_LINK_NEW="$HOME/.local/state/nix/profile"
        let NIX_LINK_NEW = $"($env.HOME)/.local/state/nix/profile"
#     fi
    }
#     if [ -e "$NIX_LINK_NEW" ]; then
    if $NIX_LINK_NEW != "" {
#         NIX_LINK="$NIX_LINK_NEW"
        let NIX_LINK = $NIX_LINK_NEW
#     else
    } else {
#     fi
    }

#     # Set up environment.
#     # This part should be kept in sync with nixpkgs:nixos/modules/programs/environment.nix
#     export NIX_PROFILES="/nix/var/nix/profiles/default $NIX_LINK"
    $env.NIX_PROFILES = $"/nix/var/nix/profiles/default ($NIX_LINK)"

#     # Populate bash completions, .desktop files, etc
#     if [ -z "${XDG_DATA_DIRS-}" ]; then
    if "XDG_DATA_DIRS" in $env_cols {
#         # According to XDG spec the default is /usr/local/share:/usr/share, don't set something that prevents that default
#         export XDG_DATA_DIRS="/usr/local/share:/usr/share:$NIX_LINK/share:/nix/var/nix/profiles/default/share"
        $env.XDG_DATA_DIRS = $"/usr/local/share:/usr/share:($NIX_LINK)/share:/nix/var/nix/profiles/default/share"
#     else
    } else {
#         export XDG_DATA_DIRS="$XDG_DATA_DIRS:$NIX_LINK/share:/nix/var/nix/profiles/default/share"
        $env.XDG_DATA_DIRS = $"($NIX_LINK)/share:/nix/var/nix/profiles/default/share"
#     fi
    }

#     # Set $NIX_SSL_CERT_FILE so that Nixpkgs applications like curl work.
#     if [ -e /etc/ssl/certs/ca-certificates.crt ]; then # NixOS, Ubuntu, Debian, Gentoo, Arch
    if ("/etc/ssl/certs/ca-certificates.crt" | path exists) {
#         export NIX_SSL_CERT_FILE=/etc/ssl/certs/ca-certificates.crt
        $env.NIX_SSL_CERT_FILE = "/etc/ssl/certs/ca-certificates.crt"
#     elif [ -e /etc/ssl/ca-bundle.pem ]; then # openSUSE Tumbleweed
    } else if ("/etc/ssl/ca-bundle.pem" | path exists) {
#         export NIX_SSL_CERT_FILE=/etc/ssl/ca-bundle.pem
        $env.NIX_SSL_CERT_FILE = "/etc/ssl/ca-bundle.pem"
#     elif [ -e /etc/ssl/certs/ca-bundle.crt ]; then # Old NixOS
    } else if ("/etc/ssl/certs/ca-bundle.crt" | path exists) {
#         export NIX_SSL_CERT_FILE=/etc/ssl/certs/ca-bundle.crt
        $env.NIX_SSL_CERT_FILE = "/etc/ssl/certs/ca-bundle.crt"
#     elif [ -e /etc/pki/tls/certs/ca-bundle.crt ]; then # Fedora, CentOS
    } else if ("/etc/pki/tls/certs/ca-bundle.crt" | path exists) {
#         export NIX_SSL_CERT_FILE=/etc/pki/tls/certs/ca-bundle.crt
        $env.NIX_SSL_CERT_FILE = "/etc/pki/tls/certs/ca-bundle.crt"
#     elif [ -e "$NIX_LINK/etc/ssl/certs/ca-bundle.crt" ]; then # fall back to cacert in Nix profile
    } else if ($"($NIX_LINK)/etc/ssl/certs/ca-bundle.crt" | path exists) {
#         export NIX_SSL_CERT_FILE="$NIX_LINK/etc/ssl/certs/ca-bundle.crt"
        $env.NIX_SSL_CERT_FILE = $"($NIX_LINK)/etc/ssl/certs/ca-bundle.crt"
#     elif [ -e "$NIX_LINK/etc/ca-bundle.crt" ]; then # old cacert in Nix profile
    } else if ($"($NIX_LINK)/etc/ca-bundle.crt" | path exists) {
#         export NIX_SSL_CERT_FILE="$NIX_LINK/etc/ca-bundle.crt"
        $env.NIX_SSL_CERT_FILE = $"($NIX_LINK)/etc/ca-bundle.crt"
#     fi
    }

#     # Only use MANPATH if it is already set. In general `man` will just simply
#     # pick up `.nix-profile/share/man` because is it close to `.nix-profile/bin`
#     # which is in the $PATH. For more info, run `manpath -d`.
#     if [ -n "${MANPATH-}" ]; then
    if "MANPATH" in $env_cols {
#         export MANPATH="$NIX_LINK/share/man:$MANPATH"
        $env.MANPATH = $"($NIX_LINK)/share/man:($env.MANPATH)"
#     fi
    }

#     export PATH="$NIX_LINK/bin:$PATH"
    std path add $"($NIX_LINK)/bin"
#     unset NIX_LINK NIX_LINK_NEW
# fi
}

Add to $nu.env-path with source activate_nix.nu.