Merge pull request #39407 from dtzWill/feature/check-nix.conf

nixos/nix-daemon: optionally (on by default) check nix.conf can be read

1 files changed, 13 insertions, 2 deletions

diff --git a/nixos/modules/services/misc/nix-daemon.nix b/nixos/modules/services/misc/nix-daemon.nix
index f2d34560a718..9c428d7a422d 100644
--- a/nixos/modules/services/misc/nix-daemon.nix
+++ b/nixos/modules/services/misc/nix-daemon.nix
@@ -33,7 +33,7 @@ let
       sh = pkgs.runtimeShell;
       binshDeps = pkgs.writeReferencesToFile sh;
     in
-      pkgs.runCommand "nix.conf" { extraOptions = cfg.extraOptions; } ''
+      pkgs.runCommand "nix.conf" { extraOptions = cfg.extraOptions; } (''
         ${optionalString (!isNix20) ''
           extraPaths=$(for i in $(cat ${binshDeps}); do if test -d $i; then echo $i; fi; done)
         ''}
@@ -62,7 +62,11 @@ let
         ''}
         $extraOptions
         END
-      '';
+      '' + optionalString cfg.checkConfig ''
+        echo "Checking that Nix can read nix.conf..."
+        ln -s $out ./nix.conf
+        NIX_CONF_DIR=$PWD ${cfg.package}/bin/nix show-config >/dev/null
+      '');
 
 in
 
@@ -349,6 +353,13 @@ in
         '';
       };
 
+      checkConfig = mkOption {
+        type = types.bool;
+        default = true;
+        description = ''
+          If enabled (the default), checks that Nix can parse the generated nix.conf.
+        '';
+      };
     };
 
   };