gtk: add cursor theme configuration (#2481)

* gtk: add cursor theme configuration

- Added the `cursorTheme` under the gtk module.
- Added tests for the gtk3 settings file generation, and renamed
  the gtk2 unit test expected file for clarity.
- Added guard against generating a blank `gtk.css` when `cfg.extraCss`
  is empty.
- Replaced `concatMapStrings` calls with `concatStringsSep`. The library function
  `concatMapStrings` generates an intemediate list which is then passed to
  `concatStringsSep`, As we are not performing other transformation except
  the addition of newlines, a direct call to `concatStringsSep` is sufficient.
- Updated description of examples to be more general "~/.config" -> "$XDG_CONFIG_HOME".
- Update helper functions `toGtk3Ini` and `formatGtk2Option` to use the library
  function `boolToString` and escape the separator in the key name.

* xcursor: delegate GTK cursor settings to gtk.cursorTheme

- Added deprecation warning for GTK settings in the `xsession.cursorTheme` module.
- Modified config section to use `gtk.cursorTheme` for GTK cursor settings.

modules/misc/gtk.nix

@@ -11,23 +11,19 @@ let
 
   toGtk3Ini = generators.toINI {
     mkKeyValue = key: value:
-      let
+      let value' = if isBool value then boolToString value else toString value;
-        value' = if isBool value then
+      in "${escape [ "=" ] key}=${value'}";
-          (if value then "true" else "false")
-        else
-          toString value;
-      in "${key}=${value'}";
   };
 
   formatGtk2Option = n: v:
     let
       v' = if isBool v then
-        (if v then "true" else "false")
+        boolToString value
       else if isString v then
         ''"${v}"''
       else
         toString v;
-    in "${n} = ${v'}";
+    in "${escape [ "=" ] n} = ${v'}";
 
   themeType = types.submodule {
     options = {
@@ -50,6 +46,57 @@ let
     };
   };
 
+  iconThemeType = types.submodule {
+    options = {
+      package = mkOption {
+        type = types.nullOr types.package;
+        default = null;
+        example = literalExpression "pkgs.adwaita-icon-theme";
+        description = ''
+          Package providing the icon theme. This package will be installed
+          to your profile. If <literal>null</literal> then the theme
+          is assumed to already be available in your profile.
+        '';
+      };
+
+      name = mkOption {
+        type = types.str;
+        example = "Adwaita";
+        description = "The name of the icon theme within the package.";
+      };
+    };
+  };
+
+  cursorThemeType = types.submodule {
+    options = {
+      package = mkOption {
+        type = types.nullOr types.package;
+        default = null;
+        example = literalExpression "pkgs.vanilla-dmz";
+        description = ''
+          Package providing the cursor theme. This package will be installed
+          to your profile. If <literal>null</literal> then the theme
+          is assumed to already be available in your profile.
+        '';
+      };
+
+      name = mkOption {
+        type = types.str;
+        example = "Vanilla-DMZ";
+        description = "The name of the cursor theme within the package.";
+      };
+
+      size = mkOption {
+        type = types.nullOr types.int;
+        default = null;
+        example = 16;
+        description = ''
+          The size of the cursor.
+        '';
+      };
+    };
+  };
+
 in {
   meta.maintainers = [ maintainers.rycee ];
 
@@ -71,8 +118,14 @@ in {
         '';
       };
 
+      cursorTheme = mkOption {
+        type = types.nullOr cursorThemeType;
+        default = null;
+        description = "The cursor theme to use.";
+      };
+
       iconTheme = mkOption {
-        type = types.nullOr themeType;
+        type = types.nullOr iconThemeType;
         default = null;
         description = "The icon theme to use.";
       };
@@ -116,7 +169,7 @@ in {
         };
 
         extraConfig = mkOption {
-          type = with types; attrsOf (either bool (either int str));
+          type = with types; attrsOf (oneOf [ bool int str ]);
           default = { };
           example = {
             gtk-cursor-blink = false;
@@ -156,7 +209,7 @@ in {
   };
 
   config = mkIf cfg.enable (let
-    ini = optionalAttrs (cfg.font != null) {
+    gtkIni = optionalAttrs (cfg.font != null) {
       gtk-font-name = let
         fontSize =
           optionalString (cfg.font.size != null) " ${toString cfg.font.size}";
@@ -164,6 +217,11 @@ in {
     } // optionalAttrs (cfg.theme != null) { gtk-theme-name = cfg.theme.name; }
       // optionalAttrs (cfg.iconTheme != null) {
         gtk-icon-theme-name = cfg.iconTheme.name;
+      } // optionalAttrs (cfg.cursorTheme != null) {
+        gtk-cursor-theme-name = cfg.cursorTheme.name;
+      } // optionalAttrs
+      (cfg.cursorTheme != null && cfg.cursorTheme.size != null) {
+        gtk-cursor-theme-size = cfg.cursorTheme.size;
       };
 
     dconfIni = optionalAttrs (cfg.font != null) {
@@ -174,31 +232,41 @@ in {
     } // optionalAttrs (cfg.theme != null) { gtk-theme = cfg.theme.name; }
       // optionalAttrs (cfg.iconTheme != null) {
         icon-theme = cfg.iconTheme.name;
+      } // optionalAttrs (cfg.cursorTheme != null) {
+        cursor-theme = cfg.cursorTheme.name;
+      } // optionalAttrs
+      (cfg.cursorTheme != null && cfg.cursorTheme.size != null) {
+        cursor-size = cfg.cursorTheme.size;
       };
 
     optionalPackage = opt:
       optional (opt != null && opt.package != null) opt.package;
   in {
-    home.packages = optionalPackage cfg.font ++ optionalPackage cfg.theme
+    home.packages = concatMap optionalPackage [
-      ++ optionalPackage cfg.iconTheme;
+      cfg.font
+      cfg.theme
+      cfg.iconTheme
+      cfg.cursorTheme
+    ];
 
     home.file.${cfg2.configLocation}.text =
-      concatMapStrings (l: l + "\n") (mapAttrsToList formatGtk2Option ini)
+      concatStringsSep "\n" (mapAttrsToList formatGtk2Option gtkIni)
       + cfg2.extraConfig;
 
     home.sessionVariables.GTK2_RC_FILES = cfg2.configLocation;
 
     xdg.configFile."gtk-3.0/settings.ini".text =
-      toGtk3Ini { Settings = ini // cfg3.extraConfig; };
+      toGtk3Ini { Settings = gtkIni // cfg3.extraConfig; };
 
-    xdg.configFile."gtk-3.0/gtk.css".text = cfg3.extraCss;
+    xdg.configFile."gtk-3.0/gtk.css" =
+      mkIf (cfg3.extraCss != "") { text = cfg3.extraCss; };
 
     xdg.configFile."gtk-3.0/bookmarks" = mkIf (cfg3.bookmarks != [ ]) {
-      text = concatMapStrings (l: l + "\n") cfg3.bookmarks;
+      text = concatStringsSep "\n" cfg3.bookmarks;
     };
 
     xdg.configFile."gtk-4.0/settings.ini".text =
-      toGtk3Ini { Settings = ini // cfg4.extraConfig; };
+      toGtk3Ini { Settings = gtkIni // cfg4.extraConfig; };
 
     dconf.settings."org/gnome/desktop/interface" = dconfIni;
   });

modules/xcursor.nix

@@ -60,6 +60,11 @@ in {
         platforms.linux)
     ];
 
+    warnings = [''
+      GTK cursor settings will no longer be handled in the xsession.pointerCursor module in future.
+      Please use gtk.cursorTheme for GTK cursor settings instead.
+    ''];
+
     home.packages = [ cfg.package ];
 
     xsession.initExtra = ''
@@ -73,15 +78,8 @@ in {
       "Xcursor.size" = cfg.size;
     };
 
-    gtk.gtk2.extraConfig = ''
+    # TODO: deprecate after next version release.
-      gtk-cursor-theme-name="${cfg.name}"
+    gtk.cursorTheme = { inherit (cfg) package name size; };
-      gtk-cursor-theme-size=${toString cfg.size}
-    '';
-
-    gtk.gtk3.extraConfig = {
-      "gtk-cursor-theme-name" = cfg.name;
-      "gtk-cursor-theme-size" = cfg.size;
-    };
 
     # Set name in icons theme, for compatibility with AwesomeWM etc. See:
     # https://github.com/nix-community/home-manager/issues/2081

tests/modules/misc/gtk/default.nix

@@ -1,5 +1,6 @@
 {
   gtk2-basic-config = ./gtk2-basic-config.nix;
   gtk2-config-file-location = ./gtk2-config-file-location.nix;
+  gtk3-basic-settings = ./gtk3-basic-settings.nix;
 }
 

tests/modules/misc/gtk/gtk2-basic-config.nix

@@ -13,9 +13,10 @@ with lib;
 
     nmt.script = ''
       assertFileExists home-files/.gtkrc-2.0
-      assertFileContent home-files/.gtkrc-2.0 ${
+
-        ./gtk-basic-config-expected.conf
+      assertFileContent home-files/.gtkrc-2.0 \
-      }
+        ${./gtk2-basic-config-expected.conf}
+
       assertFileRegex home-path/etc/profile.d/hm-session-vars.sh \
           'GTK2_RC_FILES=.*/.gtkrc-2.0'
     '';

tests/modules/misc/gtk/gtk3-basic-settings-expected.ini

@@ -0,0 +1,3 @@
+[Settings]
+gtk-cursor-blink=false
+gtk-recent-files-limit=20

tests/modules/misc/gtk/gtk3-basic-settings.nix

@@ -0,0 +1,24 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+{
+  config = {
+    gtk = {
+      enable = true;
+      gtk3.extraConfig = {
+        gtk-cursor-blink = false;
+        gtk-recent-files-limit = 20;
+      };
+    };
+
+    test.stubs.dconf = { };
+
+    nmt.script = ''
+      assertPathExists home-files/.config/gtk-3.0
+
+      assertFileContent home-files/.config/gtk-3.0/settings.ini \
+        ${./gtk3-basic-settings-expected.ini}
+    '';
+  };
+}