From 75add386d3ff362d0a1329484efe228d14d63065 Mon Sep 17 00:00:00 2001
From: Daiderd Jordan <daiderd@gmail.com>
Date: Fri, 14 Sep 2018 21:52:12 +0200
Subject: [PATCH] installer: prefer nix from default profile

Using a nix 2.1 nix-channel/nix-env with a 2.0 nix-daemon doesn't work
because the buildenv implementation was moved to the daemon.  This means
the nix version of the target darwin system can't be used because the
daemon isn't upgraded yet.

    error: unsupported builtin function 'buildenv'
---
 pkgs/darwin-installer/configuration.nix |  2 ++
 pkgs/darwin-installer/default.nix       | 13 +++++--------
 2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/pkgs/darwin-installer/configuration.nix b/pkgs/darwin-installer/configuration.nix
index bc40563..f51c7f1 100644
--- a/pkgs/darwin-installer/configuration.nix
+++ b/pkgs/darwin-installer/configuration.nix
@@ -11,6 +11,8 @@ with lib;
   users.knownUsers = [ "nixbld1" "nixbld2" "nixbld3" "nixbld4" "nixbld5" "nixbld6" "nixbld7" "nixbld8" "nixbld9" "nixbld10" ];
 
   system.activationScripts.preUserActivation.text = mkBefore ''
+    PATH=/nix/var/nix/profiles/default/bin:$PATH
+
     darwinPath=$(NIX_PATH=${concatStringsSep ":" config.nix.nixPath} nix-instantiate --eval -E '<darwin>' 2> /dev/null) || true
     if ! test -e "$darwinPath"; then
         if test -t 1; then
diff --git a/pkgs/darwin-installer/default.nix b/pkgs/darwin-installer/default.nix
index 5346396..638f2bb 100644
--- a/pkgs/darwin-installer/default.nix
+++ b/pkgs/darwin-installer/default.nix
@@ -24,8 +24,7 @@ stdenv.mkDerivation {
   shellHook = ''
     set -e
 
-    orig_path="$PATH"
-    export PATH="${pkgs.openssh}/bin:/usr/bin:/bin:/usr/sbin:/sbin"  # ssh in case nix needs it
+    export PATH=/nix/var/nix/profiles/default/bin:${nix}/bin:${pkgs.openssh}/bin:/usr/bin:/bin:/usr/sbin:/sbin
 
     action=switch
     while [ "$#" -gt 0 ]; do
@@ -45,9 +44,7 @@ stdenv.mkDerivation {
     echo >&2 "Installing nix-darwin..."
     echo >&2
 
-    export nix=${nix}
-
-    config=$($nix/bin/nix-instantiate --eval -E '<darwin-config>' 2> /dev/null || echo "$HOME/.nixpkgs/darwin-configuration.nix")
+    config=$(nix-instantiate --eval -E '<darwin-config>' 2> /dev/null || echo "$HOME/.nixpkgs/darwin-configuration.nix")
     if ! test -f "$config"; then
         echo "copying example configuration.nix" >&2
         mkdir -p "$HOME/.nixpkgs"
@@ -61,15 +58,15 @@ stdenv.mkDerivation {
         read -p "Would you like edit the default configuration.nix before starting? [y/n] " i
         case "$i" in
             y|Y)
-                PATH="$orig_path" ''${EDITOR:-nano} "$config"
+                ''${EDITOR:-nano} "$config"
                 ;;
         esac
     fi
 
     export NIX_PATH=${nixPath}
-    system=$($nix/bin/nix-build '<darwin>' -I "user-darwin-config=$config" -A system --no-out-link)
-    export PATH=$system/sw/bin:$PATH
+    system=$(nix-build '<darwin>' -I "user-darwin-config=$config" -A system --no-out-link)
 
+    export PATH=$system/sw/bin:$PATH
     darwin-rebuild "$action" -I "user-darwin-config=$config"
 
     echo >&2