fontconfig: add module

modules/default.nix

@@ -13,6 +13,7 @@ let
   modules = [
     ./home-environment.nix
     ./manual.nix
+    ./misc/fontconfig.nix
     ./misc/gtk.nix
     ./misc/news.nix
     ./misc/pam.nix

modules/misc/fontconfig.nix

@@ -0,0 +1,41 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+
+  cfg = config.fonts.fontconfig;
+
+in
+
+{
+  meta.maintainers = [ maintainers.rycee ];
+
+  options = {
+    fonts.fontconfig = {
+      enableProfileFonts = mkOption {
+        type = types.bool;
+        default = false;
+        example = true;
+        description = ''
+          Configure fontconfig to discover fonts installed through
+          <varname>home.packages</varname> and
+          <command>nix-env</command>.
+          </para><para>
+          Note, this is only necessary on non-NixOS systems.
+        '';
+      };
+    };
+  };
+
+  config = mkIf cfg.enableProfileFonts {
+    home.file.".config/fontconfig/conf.d/10-nix-profile-fonts.conf".text = ''
+      <?xml version='1.0'?>
+      <!DOCTYPE fontconfig SYSTEM 'fonts.dtd'>
+      <fontconfig>
+        <dir>~/.nix-profile/lib/X11/fonts</dir>
+        <dir>~/.nix-profile/share/fonts</dir>
+      </fontconfig>
+    '';
+  };
+}

modules/misc/news.nix

@@ -302,6 +302,21 @@ in
           A new service is available: 'services.polybar'.
         '';
       }
+
+      {
+        time = "2017-10-09T16:38:34+00:00";
+        message = ''
+          A new module is available: 'fonts.fontconfig'.
+
+          In particular, the Boolean option
+
+              fonts.fontconfig.enableProfileFonts
+
+          was added for those who do not use NixOS and want to install
+          font packages using 'nix-env' or 'home.packages'. If you are
+          using NixOS then you do not need to enable this option.
+        '';
+      }
     ];
   };
 }