[libwnck/wip/muktupavels/tasklist-tooltips] tasklist: avoid useless tooltips

[Alberts Muktupāvels <muktupavels src gnome org>]

commit c55f49e18710e5d26cf5cc7301b140d1dc73b7c0
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Tue Oct 11 18:22:01 2022 +0300

    tasklist: avoid useless tooltips
    
    Do not show tooltip if text does not differ from button text and
    is already fully visible / not ellipsized.
    
    https://gitlab.gnome.org/GNOME/libwnck/-/issues/115

 libwnck/tasklist.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
---
diff --git a/libwnck/tasklist.c b/libwnck/tasklist.c
index 606094c4..33ac2905 100644
--- a/libwnck/tasklist.c
+++ b/libwnck/tasklist.c
@@ -590,12 +590,32 @@ wnck_button_query_tooltip (GtkWidget  *widget,
                            GtkTooltip *tooltip)
 {
   WnckButton *self;
+  GtkLabel *label;
+  char *tooltip_text;
 
   self = WNCK_BUTTON (widget);
 
   if (!self->tasklist->priv->tooltips_enabled)
     return FALSE;
 
+  label = GTK_LABEL (self->label);
+  tooltip_text = gtk_widget_get_tooltip_text (widget);
+
+  if (g_strcmp0 (gtk_label_get_text (label), tooltip_text) == 0)
+    {
+      PangoLayout *layout;
+
+      layout = gtk_label_get_layout (label);
+
+      if (!pango_layout_is_ellipsized (layout))
+        {
+          g_free (tooltip_text);
+          return FALSE;
+        }
+    }
+
+  g_free (tooltip_text);
+
   return GTK_WIDGET_CLASS (wnck_button_parent_class)->query_tooltip (widget,
                                                                      x,
                                                                      y,