Merge pull request #312268 from Cryolitia/steam

nixos/steam: add option `extraPackages`, fix CJK fonts on client

nixos/modules/programs/steam.nix

@@ -55,6 +55,7 @@ in {
             then [ package ] ++ extraPackages
             else [ package32 ] ++ extraPackages32;
         in prevLibs ++ additionalLibs;
+        extraPkgs = p: (cfg.extraPackages ++ lib.optionals (prev ? extraPkgs) (prev.extraPkgs p));
       } // lib.optionalAttrs (cfg.gamescopeSession.enable && gamescopeCfg.capSysNice)
       {
         buildFHSEnv = pkgs.buildFHSEnv.override {
@@ -71,6 +72,19 @@ in {
       '';
     };
 
+    extraPackages = lib.mkOption {
+      type = lib.types.listOf lib.types.package;
+      default = [ ];
+      example = lib.literalExpression ''
+        with pkgs; [
+          gamescope
+        ]
+      '';
+      description = ''
+        Additional packages to add to the Steam environment.
+      '';
+    };
+
     extraCompatPackages = lib.mkOption {
       type = lib.types.listOf lib.types.package;
       default = [ ];
@@ -88,6 +102,18 @@ in {
       '';
     };
 
+    fontPackages = lib.mkOption {
+      type = lib.types.listOf lib.types.package;
+      default = config.fonts.packages;
+      defaultText = lib.literalExpression "fonts.packages";
+      example = lib.literalExpression "with pkgs; [ source-han-sans ]";
+      description = ''
+        Font packages to use in Steam.
+
+        Defaults to system fonts, but could be overridden to use other fonts — useful for users who would like to customize CJK fonts used in Steam. According to the [upstream issue](https://github.com/ValveSoftware/steam-for-linux/issues/10422#issuecomment-1944396010), Steam only follows the per-user fontconfig configuration.
+      '';
+    };
+
     remotePlay.openFirewall = lib.mkOption {
       type = lib.types.bool;
       default = false;
@@ -165,6 +191,8 @@ in {
       };
     };
 
+    programs.steam.extraPackages = cfg.fontPackages;
+
     programs.gamescope.enable = lib.mkDefault cfg.gamescopeSession.enable;
     services.displayManager.sessionPackages = lib.mkIf cfg.gamescopeSession.enable [ gamescopeSessionFile ];