hyprland: add module

Ported from

  https://github.com/hyprwm/Hyprland/blob/main/nix/hm-module.nix

which was adapted from the sway module.

Co-authored-by: Robert Helgesson <robert@rycee.net>

modules/misc/news.nix

@@ -1144,6 +1144,14 @@ in
           A new module is available: 'services.swayosd'
         '';
       }
+
+      {
+        time = "2023-07-20T21:56:49+00:00";
+        condition = hostPlatform.isLinux;
+        message = ''
+          A new module is available: 'wayland.windowManager.hyprland'
+        '';
+      }
     ];
   };
 }

modules/modules.nix

@@ -330,6 +330,7 @@ let
     ./services/window-managers/bspwm/default.nix
     ./services/window-managers/fluxbox.nix
     ./services/window-managers/herbstluftwm.nix
+    ./services/window-managers/hyprland.nix
     ./services/window-managers/i3-sway/i3.nix
     ./services/window-managers/i3-sway/sway.nix
     ./services/window-managers/i3-sway/swaynag.nix

modules/services/window-managers/hyprland.nix

@@ -0,0 +1,216 @@
+{ config, lib, pkgs, ... }:
+let
+
+  cfg = config.wayland.windowManager.hyprland;
+
+in {
+  meta.maintainers = [ lib.maintainers.fufexan ];
+
+  # A few option removals and renames to aid those migrating from the upstream
+  # module.
+  imports = [
+    (lib.mkRemovedOptionModule # \
+      [ "wayland" "windowManager" "hyprland" "disableAutoreload" ]
+      "Autoreloading now always happen")
+
+    (lib.mkRemovedOptionModule # \
+      [ "wayland" "windowManager" "hyprland" "recommendedEnvironment" ]
+      "Recommended environment variables are now always set")
+
+    (lib.mkRenamedOptionModule # \
+      [ "wayland" "windowManager" "hyprland" "nvidiaPatches" ] # \
+      [ "wayland" "windowManager" "hyprland" "enableNvidiaPatches" ])
+  ];
+
+  options.wayland.windowManager.hyprland = {
+    enable = lib.mkEnableOption "Hyprland wayland compositor";
+
+    package = lib.mkPackageOption pkgs "hyprland" { };
+
+    finalPackage = lib.mkOption {
+      type = lib.types.package;
+      readOnly = true;
+      default = cfg.package.override {
+        enableXWayland = cfg.xwayland.enable;
+        hidpiXWayland = cfg.xwayland.hidpi;
+        nvidiaPatches = cfg.enableNvidiaPatches;
+      };
+      defaultText = lib.literalMD
+        "`wayland.windowManager.hyprland.package` with applied configuration";
+      description = ''
+        The Hyprland package after applying configuration.
+      '';
+    };
+
+    plugins = lib.mkOption {
+      type = with lib.types; listOf (either package path);
+      default = [ ];
+      description = ''
+        List of Hyprland plugins to use. Can either be packages or
+        absolute plugin paths.
+      '';
+    };
+
+    systemdIntegration = lib.mkOption {
+      type = lib.types.bool;
+      default = pkgs.stdenv.isLinux;
+      description = ''
+        Whether to enable {file}`hyprland-session.target` on
+        hyprland startup. This links to `graphical-session.target`.
+        Some important environment variables will be imported to systemd
+        and dbus user environment before reaching the target, including
+        - `DISPLAY`
+        - `HYPRLAND_INSTANCE_SIGNATURE`
+        - `WAYLAND_DISPLAY`
+        - `XDG_CURRENT_DESKTOP`
+      '';
+    };
+
+    xwayland = {
+      enable = lib.mkEnableOption "XWayland" // { default = true; };
+      hidpi = lib.mkEnableOption null // {
+        description = ''
+          Enable HiDPI XWayland, based on [XWayland MR 733](https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/733).
+          See <https://wiki.hyprland.org/Nix/Options-Overrides/#xwayland-hidpi> for more info.
+        '';
+      };
+    };
+
+    enableNvidiaPatches =
+      lib.mkEnableOption "patching wlroots for better Nvidia support";
+
+    settings = lib.mkOption {
+      type = with lib.types;
+        let
+          valueType = nullOr (oneOf [
+            bool
+            int
+            float
+            str
+            path
+            (attrsOf valueType)
+            (listOf valueType)
+          ]) // {
+            description = "Hyprland configuration value";
+          };
+        in valueType;
+      default = { };
+      description = ''
+        Hyprland configuration written in Nix. Entries with the same key
+        should be written as lists. Variables' and colors' names should be
+        quoted. See <https://wiki.hyprland.org> for more examples.
+
+        ::: {.note}
+        Use the [](#opt-wayland.windowManager.hyprland.plugins) option to
+        declare plugins.
+        :::
+
+      '';
+      example = lib.literalExpression ''
+        {
+          decoration = {
+            shadow_offset = "0 5";
+            "col.shadow" = "rgba(00000099)";
+          };
+
+          "$mod" = "SUPER";
+
+          bindm = [
+            # mouse movements
+            "$mod, mouse:272, movewindow"
+            "$mod, mouse:273, resizewindow"
+            "$mod ALT, mouse:272, resizewindow"
+          ];
+        }
+      '';
+    };
+
+    extraConfig = lib.mkOption {
+      type = lib.types.lines;
+      default = "";
+      example = ''
+        # window resize
+        bind = $mod, S, submap, resize
+
+        submap = resize
+        binde = , right, resizeactive, 10 0
+        binde = , left, resizeactive, -10 0
+        binde = , up, resizeactive, 0 -10
+        binde = , down, resizeactive, 0 10
+        bind = , escape, submap, reset
+        submap = reset
+      '';
+      description = ''
+        Extra configuration lines to add to `~/.config/hypr/hyprland.conf`.
+      '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    assertions = [
+      (lib.hm.assertions.assertPlatform "wayland.windowManager.hyprland" pkgs
+        lib.platforms.linux)
+    ];
+
+    warnings = let
+      inconsistent = (cfg.systemdIntegration || cfg.plugins != [ ])
+        && cfg.extraConfig == "" && cfg.settings == { };
+      warning =
+        "You have enabled hyprland.systemdIntegration or listed plugins in hyprland.plugins but do not have any configuration in hyprland.settings or hyprland.extraConfig. This is almost certainly a mistake.";
+    in lib.optional inconsistent warning;
+
+    home.packages = lib.optional (cfg.package != null) cfg.finalPackage;
+
+    xdg.configFile."hypr/hyprland.conf" = let
+      combinedSettings = cfg.settings // {
+        plugin = let
+          mkEntry = entry:
+            if lib.types.package.check entry then
+              "${entry}/lib/lib${entry.pname}.so"
+            else
+              entry;
+        in map mkEntry cfg.plugins;
+      };
+
+      shouldGenerate = cfg.systemdIntegration || cfg.extraConfig != ""
+        || combinedSettings != { };
+
+      toHyprconf = attrs:
+        let
+          mkSection = n: attrs: ''
+            ${n} {
+              ${toHyprconf attrs}}
+          '';
+          mkFields = lib.generators.toKeyValue { listsAsDuplicateKeys = true; };
+          sections = lib.filterAttrs (n: v: lib.isAttrs v) attrs;
+          fields = lib.filterAttrs (n: v: !(lib.isAttrs v)) attrs;
+        in lib.concatStringsSep "\n" (lib.mapAttrsToList mkSection sections)
+        + mkFields fields;
+    in lib.mkIf shouldGenerate {
+      text = lib.optionalString cfg.systemdIntegration ''
+        exec-once = ${pkgs.dbus}/bin/dbus-update-activation-environment --systemd DISPLAY WAYLAND_DISPLAY HYPRLAND_INSTANCE_SIGNATURE XDG_CURRENT_DESKTOP && systemctl --user start hyprland-session.target
+      '' + lib.optionalString (combinedSettings != { })
+        (toHyprconf combinedSettings)
+        + lib.optionalString (cfg.extraConfig != "") cfg.extraConfig;
+      onChange = lib.mkIf (cfg.package != null) ''
+        (  # execute in subshell so that `shopt` won't affect other scripts
+          shopt -s nullglob  # so that nothing is done if /tmp/hypr/ does not exist or is empty
+          for instance in /tmp/hypr/*; do
+            HYPRLAND_INSTANCE_SIGNATURE=''${instance##*/} ${cfg.finalPackage}/bin/hyprctl reload config-only \
+              || true  # ignore dead instance(s)
+          done
+        )
+      '';
+    };
+
+    systemd.user.targets.hyprland-session = lib.mkIf cfg.systemdIntegration {
+      Unit = {
+        Description = "Hyprland compositor session";
+        Documentation = [ "man:systemd.special(7)" ];
+        BindsTo = [ "graphical-session.target" ];
+        Wants = [ "graphical-session-pre.target" ];
+        After = [ "graphical-session-pre.target" ];
+      };
+    };
+  };
+}

tests/default.nix

@@ -232,6 +232,7 @@ import nmt {
     ./modules/services/udiskie
     ./modules/services/window-managers/bspwm
     ./modules/services/window-managers/herbstluftwm
+    ./modules/services/window-managers/hyprland
     ./modules/services/window-managers/i3
     ./modules/services/window-managers/spectrwm
     ./modules/services/window-managers/sway

tests/modules/services/window-managers/hyprland/default.nix

@@ -0,0 +1,4 @@
+{
+  hyprland-simple-config = ./simple-config.nix;
+  hyprland-inconsistent-config = ./inconsistent-config.nix;
+}

tests/modules/services/window-managers/hyprland/inconsistent-config.nix

@@ -0,0 +1,21 @@
+{ config, lib, ... }:
+
+{
+  wayland.windowManager.hyprland = {
+    enable = true;
+    package = lib.makeOverridable
+      (attrs: config.lib.test.mkStubPackage { name = "hyprland"; }) { };
+    plugins =
+      [ "/path/to/plugin1" (config.lib.test.mkStubPackage { name = "foo"; }) ];
+  };
+
+  test.asserts.warnings.expected = [
+    "You have enabled hyprland.systemdIntegration or listed plugins in hyprland.plugins but do not have any configuration in hyprland.settings or hyprland.extraConfig. This is almost certainly a mistake."
+  ];
+  test.asserts.warnings.enable = true;
+
+  nmt.script = ''
+    config=home-files/.config/hypr/hyprland.conf
+    assertFileExists "$config"
+  '';
+}

tests/modules/services/window-managers/hyprland/simple-config.conf

@@ -0,0 +1,30 @@
+exec-once = /nix/store/00000000000000000000000000000000-dbus/bin/dbus-update-activation-environment --systemd DISPLAY WAYLAND_DISPLAY HYPRLAND_INSTANCE_SIGNATURE XDG_CURRENT_DESKTOP && systemctl --user start hyprland-session.target
+decoration {
+  col.shadow=rgba(00000099)
+shadow_offset=0 5
+}
+
+input {
+  touchpad {
+  scroll_factor=0.300000
+}
+accel_profile=flat
+follow_mouse=1
+kb_layout=ro
+}
+$mod=SUPER
+bindm=$mod, mouse:272, movewindow
+bindm=$mod, mouse:273, resizewindow
+bindm=$mod ALT, mouse:272, resizewindow
+plugin=/path/to/plugin1
+plugin=/nix/store/00000000000000000000000000000000-foo/lib/libfoo.so
+# window resize
+bind = $mod, S, submap, resize
+
+submap = resize
+binde = , right, resizeactive, 10 0
+binde = , left, resizeactive, -10 0
+binde = , up, resizeactive, 0 -10
+binde = , down, resizeactive, 0 10
+bind = , escape, submap, reset
+submap = reset

tests/modules/services/window-managers/hyprland/simple-config.nix

@@ -0,0 +1,53 @@
+{ config, lib, ... }:
+
+{
+  wayland.windowManager.hyprland = {
+    enable = true;
+    package = lib.makeOverridable
+      (attrs: config.lib.test.mkStubPackage { name = "hyprland"; }) { };
+    plugins =
+      [ "/path/to/plugin1" (config.lib.test.mkStubPackage { name = "foo"; }) ];
+    settings = {
+      decoration = {
+        shadow_offset = "0 5";
+        "col.shadow" = "rgba(00000099)";
+      };
+
+      "$mod" = "SUPER";
+
+      input = {
+        kb_layout = "ro";
+        follow_mouse = 1;
+        accel_profile = "flat";
+        touchpad = { scroll_factor = 0.3; };
+      };
+
+      bindm = [
+        # mouse movements
+        "$mod, mouse:272, movewindow"
+        "$mod, mouse:273, resizewindow"
+        "$mod ALT, mouse:272, resizewindow"
+      ];
+    };
+    extraConfig = ''
+      # window resize
+      bind = $mod, S, submap, resize
+
+      submap = resize
+      binde = , right, resizeactive, 10 0
+      binde = , left, resizeactive, -10 0
+      binde = , up, resizeactive, 0 -10
+      binde = , down, resizeactive, 0 10
+      bind = , escape, submap, reset
+      submap = reset
+    '';
+  };
+
+  nmt.script = ''
+    config=home-files/.config/hypr/hyprland.conf
+    assertFileExists "$config"
+
+    normalizedConfig=$(normalizeStorePaths "$config")
+    assertFileContent "$normalizedConfig" ${./simple-config.conf}
+  '';
+}