autorandr: remove blank lines from config

Fixes #1249.

modules/programs/autorandr.nix

@@ -244,21 +244,21 @@ let
     ]);
   fingerprintToString = name: edid: "${name} ${edid}";
   configToString = name: config:
-    if config.enable then ''
+    if config.enable then
-      output ${name}
+      concatStringsSep "\n" ([ "output ${name}" ]
-      ${optionalString (config.position != "") "pos ${config.position}"}
+        ++ optional (config.position != "") "pos ${config.position}"
-      ${optionalString config.primary "primary"}
+        ++ optional config.primary "primary"
-      ${optionalString (config.dpi != null) "dpi ${toString config.dpi}"}
+        ++ optional (config.dpi != null) "dpi ${toString config.dpi}"
-      ${optionalString (config.gamma != "") "gamma ${config.gamma}"}
+        ++ optional (config.gamma != "") "gamma ${config.gamma}"
-      ${optionalString (config.mode != "") "mode ${config.mode}"}
+        ++ optional (config.mode != "") "mode ${config.mode}"
-      ${optionalString (config.rate != "") "rate ${config.rate}"}
+        ++ optional (config.rate != "") "rate ${config.rate}"
-      ${optionalString (config.rotate != null) "rotate ${config.rotate}"}
+        ++ optional (config.rotate != null) "rotate ${config.rotate}"
-      ${optionalString (config.scale != null)
+        ++ optional (config.transform != null) ("transform "
-      ((if config.scale.method == "factor" then "scale" else "scale-from")
+          + concatMapStringsSep "," toString (flatten config.transform))
-        + " ${toString config.scale.x}x${toString config.scale.y}")}
+        ++ optional (config.scale != null)
-      ${optionalString (config.transform != null) ("transform "
+        ((if config.scale.method == "factor" then "scale" else "scale-from")
-        + concatMapStringsSep "," toString (flatten config.transform))}
+          + " ${toString config.scale.x}x${toString config.scale.y}"))
-    '' else ''
+    else ''
       output ${name}
       off
     '';