Launcher: show accels in tooltip

data/dock.metainfo.xml.in

@@ -39,6 +39,7 @@
       </description>
       <issues>
         <issue url="https://github.com/elementary/dock/issues/455">Background tasks: no menu</issue>
+        <issue url="https://github.com/elementary/dock/issues/486">Add super number shortcuts to tooltips</issue>
         <issue url="https://github.com/elementary/dock/issues/505">No app tooltip shows when Hide Dock is set to Never while using Wayland</issue>
         <issue url="https://github.com/elementary/dock/issues/520">"Keep in Dock" Not Working For Most Applications</issue>
         <issue url="https://github.com/elementary/dock/issues/527">Drag and drop an app window into the workspace switcher</issue>

src/AppSystem/Launcher.vala

@@ -10,12 +10,15 @@ public class Dock.Launcher : BaseItem {
 
     private const int DND_TIMEOUT = 1000;
 
+    private static Settings keybinding_settings;
     private static Settings? notify_settings;
 
     static construct {
         if (SettingsSchemaSource.get_default ().lookup ("io.elementary.notifications", true) != null) {
             notify_settings = new Settings ("io.elementary.notifications");
         }
+
+        keybinding_settings = new GLib.Settings ("io.elementary.dock.keybindings");
     }
 
     // Matches icon size and padding in Launcher.css
@@ -89,7 +92,9 @@ public class Dock.Launcher : BaseItem {
         popover_menu.set_offset (0, -1);
         popover_menu.set_parent (this);
 
-        tooltip_text = app.app_info.get_display_name ();
+        update_tooltip ();
+        notify["current-pos"].connect (update_tooltip);
+        keybinding_settings.changed.connect (update_tooltip);
 
         image = new Gtk.Image ();
 
@@ -368,6 +373,19 @@ public class Dock.Launcher : BaseItem {
         });
     }
 
+    private void update_tooltip () {
+        string[] accels = {};
+        var index = (int) current_pos / ItemManager.get_launcher_size ();
+        if (index < 9) {
+            accels = keybinding_settings.get_strv ("launch-dock-%i".printf (index + 1));
+        }
+
+        tooltip_text = Granite.markup_accel_tooltip (
+            accels,
+            app.app_info.get_display_name ()
+        );
+    }
+
     protected override bool drag_cancelled (Gdk.Drag drag, Gdk.DragCancelReason reason) {
         if (app.pinned && reason == NO_TARGET) {
             var popover = new PoofPopover ();