Ensure nix channels are functioning

scripts/lib/action.fish

@@ -10,14 +10,15 @@ function runActionSetup -V dir
     and runHook prepareNix || installNixPkgs
 
     and echo "Flagging repository as safe..."
-    and sudo git config --system --add safe.directory (realpath "$(status dirname)/../..")
+    and sudo git config --system --add safe.directory (realpath -m "$(status dirname)/../..")
     and runHook actionPreRun || true
 end
 
-function runActionConfigure
+function runActionConfigure -V dir
     and if [ -z "$CONFIG_NAME" ]
+        source "$dir/settings.fish"
         selectProfile config
-        set -x CONFIG_NAME "$config"
+        set -gx CONFIG_NAME "$config"
     end
 end
 
@@ -37,30 +38,33 @@ function runAction -V dir
 end
 
 function runSetupUserAction -V dir
-    if [ (id -u) -eq 0 ]
-        set -l cmdline (cat /proc/$fish_pid/cmdline | string split0)
-
-        if [ -z "$TMUX" ]
-            runActionSetup
-            tmux new-session -e "CONFIG_NAME=$CONFIG_NAME" $cmdline
-        else
     source "$dir/settings.fish"
+    runActionSetup
     runActionConfigure
-            set -l sudoConfig "/etc/sudoers.d/PortValhalla"
+    set -l env "CONFIG_NAME=$CONFIG_NAME"
     set -l name (getOSConfig setupUser.name)
 
-            and begin
+    if [ "$USER" != "$name" ]
+        set -l cmdline (cat /proc/$fish_pid/cmdline | string split0)
+
+        if [ (id -u) -ne 0 ]
+            sudo --set-home --preserve-env $cmdline
+        else
+            if [ -z "$TMUX" ]
+                tmux new-session -e "$env" $cmdline
+            else
+                set -l sudoConfig "/etc/sudoers.d/PortValhalla"
+
+                begin
                     echo "Creating setup user"
 
                     and useradd \
                             --comment "PortValhalla Setup User" \
                             --system \
-                    --no-user-group \
                             --groups nix-users \
                             --create-home \
                             --uid (getOSConfig setupUser.id --json) \
                             "$name"
-            end
 
                     and begin
                         echo "$name ALL=(ALL:ALL) NOPASSWD: ALL"
@@ -71,6 +75,8 @@ function runSetupUserAction -V dir
                     rm "$sudoConfig"
                     userdel -rf "$name"
                 end
+            end
+        end
     else
         $argv
     end

scripts/lib/nix.fish

@@ -3,10 +3,14 @@ begin
     set -l config "$dir/config.fish"
     set nixPkgsDir "/nix/var/nix/profiles/per-user/root/channels/nixpkgs"
 
+    function __isNixModule -a path
+        nix-instantiate --eval --expr "{ path }: import path" --argstr path "$path" &>/dev/null
+    end
+
     function downloadNixPkgs -V config
         source "$config"
 
-        if [ ! -d "$nixPkgsCache" ]
+        if ! __isNixModule "$nixPkgsCache"
             mkdir -p "$nixPkgsCache"
             and git clone https://github.com/NixOS/nixpkgs.git --depth=1 -b "$nixPkgsVersion" "$nixPkgsCache"
             and rm -rf "$nixPkgsCache/.git"
@@ -16,8 +20,8 @@ begin
     function installNixPkgs -V config -V nixPkgsDir
         source "$config"
 
-        if [ ! -d "$nixPkgsDir" ]
+        if ! __isNixModule "$nixPkgsDir"
-            if [ ! -d "$nixPkgsCache" ]
+            if ! __isNixModule "$nixPkgsCache"
                 downloadNixPkgs
             end