GtkLabel: better treatment for ellipsized links

When links are entirely hidden in an ellipsis, don't let
them be activated by clicking and skip them when moving
the focus around.

This commit depends on enhancements in pango 1.36.7 which
make it possible to find the ellipsed runs in a PangoLayout.
With older pango, things will work the same way as before.

https://bugzilla.gnome.org/show_bug.cgi?id=668258

diff --git a/gtk/gtklabel.c b/gtk/gtklabel.c
index cf60cf3cf7b1463c81a0bae7752ed047831611e9..d5377ae5878352e5a135c5989f3e694f73c30100 100644 (file)
--- a/gtk/gtklabel.c
+++ b/gtk/gtklabel.c
@@ -4561,6 +4561,53 @@ get_layout_index (GtkLabel *label,
   return inside;
 }
 
+static gboolean
+range_is_in_ellipsis (GtkLabel *label,
+                      gint      start,
+                      gint      end)
+{
+  GtkLabelPrivate *priv = label->priv;
+  PangoLayoutIter *iter;
+  gboolean in_ellipsis;
+
+  if (!priv->ellipsize)
+    return FALSE;
+
+  gtk_label_ensure_layout (label);
+
+  if (!pango_layout_is_ellipsized (priv->layout))
+    return FALSE;
+
+  iter = pango_layout_get_iter (priv->layout);
+
+  in_ellipsis = FALSE;
+
+  do {
+    PangoLayoutRun *run;
+
+    run = pango_layout_iter_get_run_readonly (iter);
+    if (run)
+      {
+        PangoItem *item;
+
+        item = ((PangoGlyphItem*)run)->item;
+
+        if (item->offset <= start && end <= item->offset + item->length)
+          {
+            if (item->analysis.flags & PANGO_ANALYSIS_FLAG_IS_ELLIPSIS)
+              in_ellipsis = TRUE;
+            break;
+          }
+        else if (item->offset + item->length >= end)
+          break;
+      }
+  } while (pango_layout_iter_next_run (iter));
+
+  pango_layout_iter_free (iter);
+
+  return in_ellipsis;
+}
+
 static void
 gtk_label_select_word (GtkLabel *label)
 {
@@ -4588,6 +4635,7 @@ gtk_label_grab_focus (GtkWidget *widget)
   GtkLabelPrivate *priv = label->priv;
   gboolean select_on_focus;
   GtkLabelLink *link;
+  GList *l;
 
   if (priv->select_info == NULL)
     return;
@@ -4608,10 +4656,17 @@ gtk_label_grab_focus (GtkWidget *widget)
     {
       if (priv->select_info->links && !priv->in_click)
         {
-          link = priv->select_info->links->data;
-          priv->select_info->selection_anchor = link->start;
-          priv->select_info->selection_end = link->start;
-          _gtk_label_accessible_focus_link_changed (label);
+          for (l = priv->select_info->links; l; l = l->next)
+            {
+              link = l->data;
+              if (!range_is_in_ellipsis (label, link->start, link->end))
+                {
+                  priv->select_info->selection_anchor = link->start;
+                  priv->select_info->selection_end = link->start;
+                  _gtk_label_accessible_focus_link_changed (label);
+                  break;
+                }
+            }
         }
     }
 }
@@ -4634,11 +4689,16 @@ gtk_label_focus (GtkWidget        *widget,
           focus_link = gtk_label_get_focus_link (label);
           if (focus_link && direction == GTK_DIR_TAB_BACKWARD)
             {
-              l = g_list_last (info->links);
-              focus_link = l->data;
-              info->selection_anchor = focus_link->start;
-              info->selection_end = focus_link->start;
-              _gtk_label_accessible_focus_link_changed (label);
+              for (l = g_list_last (info->links); l; l = l->prev)
+                {
+                  focus_link = l->data;
+                  if (!range_is_in_ellipsis (label, focus_link->start, focus_link->end))
+                    {
+                      info->selection_anchor = focus_link->start;
+                      info->selection_end = focus_link->start;
+                      _gtk_label_accessible_focus_link_changed (label);
+                    }
+                }
             }
         }
 
@@ -4664,9 +4724,12 @@ gtk_label_focus (GtkWidget        *widget,
 
             if (link->start > index)
               {
-                gtk_label_select_region_index (label, link->start, link->start);
-                _gtk_label_accessible_focus_link_changed (label);
-                return TRUE;
+                if (!range_is_in_ellipsis (label, link->start, link->end))
+                  {
+                    gtk_label_select_region_index (label, link->start, link->start);
+                    _gtk_label_accessible_focus_link_changed (label);
+                    return TRUE;
+                  }
               }
           }
       else if (direction == GTK_DIR_TAB_BACKWARD)
@@ -4676,9 +4739,12 @@ gtk_label_focus (GtkWidget        *widget,
 
             if (link->end < index)
               {
-                gtk_label_select_region_index (label, link->start, link->start);
-                _gtk_label_accessible_focus_link_changed (label);
-                return TRUE;
+                if (!range_is_in_ellipsis (label, link->start, link->end))
+                  {
+                    gtk_label_select_region_index (label, link->start, link->start);
+                    _gtk_label_accessible_focus_link_changed (label);
+                    return TRUE;
+                  }
               }
           }
 
@@ -4697,6 +4763,12 @@ gtk_label_focus (GtkWidget        *widget,
             }
           else
             l = info->links;
+          for (; l; l = l->next)
+            {
+              GtkLabelLink *link = l->data;
+              if (!range_is_in_ellipsis (label, link->start, link->end))
+                break;
+            }
           break;
 
         case GTK_DIR_TAB_BACKWARD:
@@ -4707,6 +4779,12 @@ gtk_label_focus (GtkWidget        *widget,
             }
           else
             l = g_list_last (info->links);
+          for (; l; l = l->prev)
+            {
+              GtkLabelLink *link = l->data;
+              if (!range_is_in_ellipsis (label, link->start, link->end))
+                break;
+            }
           break;
 
         default:
@@ -5114,7 +5192,8 @@ gtk_label_motion (GtkWidget      *widget,
                   link = l->data;
                   if (index >= link->start && index <= link->end)
                     {
-                      found = TRUE;
+                      if (!range_is_in_ellipsis (label, link->start, link->end))
+                        found = TRUE;
                       break;
                     }
                 }