less: list options in correct order

modules/programs/less.nix

@@ -43,10 +43,11 @@ in
               int
               str
             ];
+            attrs = attrsOf (either scalar (listOf scalar));
           in
-          attrsOf (either scalar (listOf scalar));
-        default = { };
-        description = "GNU-style options to be set via {env}`$LESS`.";
+          coercedTo attrs (lib.cli.toGNUCommandLine { }) (listOf str);
+        default = [ ];
+        description = "Options to be set via {env}`$LESS`.";
         example = {
           RAW-CONTROL-CHARS = true;
           quiet = true;
@@ -61,10 +62,10 @@ in
 
     xdg.configFile."lesskey" = lib.mkIf (cfg.config != "") { text = cfg.config; };
 
-    programs.less.config = lib.mkIf (cfg.options != { }) (
+    programs.less.config = lib.mkIf (cfg.options != [ ]) (
       lib.mkBefore ''
         #env
-        LESS = ${lib.cli.toGNUCommandLineShell { } cfg.options}
+        LESS = ${lib.concatStringsSep " " cfg.options}
       ''
     );
   };

tests/modules/programs/less/correct-option-order.nix

@@ -0,0 +1,30 @@
+{ lib, ... }:
+
+{
+  programs.less = {
+    enable = true;
+    options = lib.mkMerge [
+      {
+        quiet = true;
+        use-color = true;
+      }
+      (lib.mkAfter {
+        color = [
+          "HkK" # header: gray
+          "Mkb" # marks: blue
+        ];
+      })
+      (lib.mkOrder 2000 {
+        prompt = "s%f";
+      })
+    ];
+  };
+
+  nmt.script = ''
+    assertFileExists home-files/.config/lesskey
+    assertFileContent home-files/.config/lesskey ${builtins.toFile "lesskey.expected" ''
+      #env
+      LESS = --quiet --use-color --color HkK --color Mkb --prompt s%f
+    ''}
+  '';
+}

tests/modules/programs/less/default.nix

@@ -1,4 +1,5 @@
 {
+  less-correct-option-order = ./correct-option-order.nix;
   less-custom-config = ./custom-config.nix;
   less-custom-options = ./custom-options.nix;
   less-custom-options-and-config = ./custom-options-and-config.nix;