[gtk/matthiasc/for-master] label: Optimize GtkLabel setters

[Matthias Clasen <matthiasc src gnome org>]

commit 0db504edde63eb77e801a5b8f4e70008e77d64dd
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Nov 11 10:35:09 2020 -0500

    label: Optimize GtkLabel setters
    
    The overarching goal here is to not queue a resize
    unless something has actually changed. In columnview
    scenarios, we often deal with hundreds of labels.
    
    Labels are cattle, not pets.

 gtk/gtklabel.c | 67 ++++++++++++++++++++++++++++++----------------------------
 1 file changed, 35 insertions(+), 32 deletions(-)
---
diff --git a/gtk/gtklabel.c b/gtk/gtklabel.c
index 6aedef6dd0..26c6419460 100644
--- a/gtk/gtklabel.c
+++ b/gtk/gtklabel.c
@@ -449,7 +449,7 @@ static gboolean gtk_label_query_tooltip     (GtkWidget        *widget,
 
 static void gtk_label_set_text_internal          (GtkLabel      *self,
                                                  char          *str);
-static void gtk_label_set_label_internal         (GtkLabel      *self,
+static gboolean gtk_label_set_label_internal     (GtkLabel      *self,
                                                  char          *str);
 static gboolean gtk_label_set_use_markup_internal    (GtkLabel  *self,
                                                       gboolean   val);
@@ -1702,15 +1702,22 @@ gtk_label_set_text_internal (GtkLabel *self,
   gtk_label_select_region_index (self, 0, 0);
 }
 
-static void
+static gboolean
 gtk_label_set_label_internal (GtkLabel *self,
-                             char     *str)
+                              char     *str)
 {
-  g_free (self->label);
+  if (g_strcmp0 (str, self->label) == 0)
+    {
+      g_free (str);
+      return FALSE;
+    }
 
+  g_free (self->label);
   self->label = str;
 
   g_object_notify_by_pspec (G_OBJECT (self), label_props[PROP_LABEL]);
+
+  return TRUE;
 }
 
 static gboolean
@@ -1784,7 +1791,7 @@ gtk_label_recalculate (GtkLabel *self)
  * @str: The text you want to set
  *
  * Sets the text within the #GtkLabel widget. It overwrites any text that
- * was there before.  
+ * was there before.
  *
  * This function will clear any previously set mnemonic accelerators, and
  * set the #GtkLabel:use-underline property to %FALSE as a side effect.
@@ -1796,17 +1803,16 @@ gtk_label_recalculate (GtkLabel *self)
  **/
 void
 gtk_label_set_text (GtkLabel    *self,
-                   const char *str)
+                    const char *str)
 {
   g_return_if_fail (GTK_IS_LABEL (self));
-  
+
   g_object_freeze_notify (G_OBJECT (self));
 
-  gtk_label_set_label_internal (self, g_strdup (str ? str : ""));
-  gtk_label_set_use_markup_internal (self, FALSE);
-  gtk_label_set_use_underline_internal (self, FALSE);
-  
-  gtk_label_recalculate (self);
+  if (gtk_label_set_label_internal (self, g_strdup (str ? str : "")) ||
+      gtk_label_set_use_markup_internal (self, FALSE) ||
+      gtk_label_set_use_underline_internal (self, FALSE))
+    gtk_label_recalculate (self);
 
   g_object_thaw_notify (G_OBJECT (self));
 }
@@ -1882,14 +1888,14 @@ gtk_label_get_attributes (GtkLabel *self)
  **/
 void
 gtk_label_set_label (GtkLabel    *self,
-                    const char *str)
+                     const char *str)
 {
   g_return_if_fail (GTK_IS_LABEL (self));
 
   g_object_freeze_notify (G_OBJECT (self));
 
-  gtk_label_set_label_internal (self, g_strdup (str ? str : ""));
-  gtk_label_recalculate (self);
+  if (gtk_label_set_label_internal (self, g_strdup (str ? str : "")))
+    gtk_label_recalculate (self);
 
   g_object_thaw_notify (G_OBJECT (self));
 }
@@ -2413,11 +2419,10 @@ gtk_label_set_markup (GtkLabel    *self,
 
   g_object_freeze_notify (G_OBJECT (self));
 
-  gtk_label_set_label_internal (self, g_strdup (str ? str : ""));
-  gtk_label_set_use_markup_internal (self, TRUE);
-  gtk_label_set_use_underline_internal (self, FALSE);
-
-  gtk_label_recalculate (self);
+  if (gtk_label_set_label_internal (self, g_strdup (str ? str : "")) ||
+      gtk_label_set_use_markup_internal (self, TRUE) ||
+      gtk_label_set_use_underline_internal (self, FALSE))
+    gtk_label_recalculate (self);
 
   g_object_thaw_notify (G_OBJECT (self));
 }
@@ -2445,11 +2450,10 @@ gtk_label_set_markup_with_mnemonic (GtkLabel    *self,
 
   g_object_freeze_notify (G_OBJECT (self));
 
-  gtk_label_set_label_internal (self, g_strdup (str ? str : ""));
-  gtk_label_set_use_markup_internal (self, TRUE);
-  gtk_label_set_use_underline_internal (self, TRUE);
-
-  gtk_label_recalculate (self);
+  if (gtk_label_set_label_internal (self, g_strdup (str ? str : "")) ||
+      gtk_label_set_use_markup_internal (self, TRUE) ||
+      gtk_label_set_use_underline_internal (self, TRUE))
+    gtk_label_recalculate (self);
 
   g_object_thaw_notify (G_OBJECT (self));
 }
@@ -3568,11 +3572,10 @@ gtk_label_set_text_with_mnemonic (GtkLabel    *self,
 
   g_object_freeze_notify (G_OBJECT (self));
 
-  gtk_label_set_label_internal (self, g_strdup (str));
-  gtk_label_set_use_markup_internal (self, FALSE);
-  gtk_label_set_use_underline_internal (self, TRUE);
-  
-  gtk_label_recalculate (self);
+  if (gtk_label_set_label_internal (self, g_strdup (str)) ||
+      gtk_label_set_use_markup_internal (self, FALSE) ||
+      gtk_label_set_use_underline_internal (self, TRUE))
+    gtk_label_recalculate (self);
 
   g_object_thaw_notify (G_OBJECT (self));
 }
@@ -4825,7 +4828,7 @@ gtk_label_get_layout_offsets (GtkLabel *self,
  **/
 void
 gtk_label_set_use_markup (GtkLabel *self,
-                         gboolean  setting)
+                          gboolean  setting)
 {
   g_return_if_fail (GTK_IS_LABEL (self));
 
@@ -4865,7 +4868,7 @@ gtk_label_get_use_markup (GtkLabel *self)
  */
 void
 gtk_label_set_use_underline (GtkLabel *self,
-                            gboolean  setting)
+                             gboolean  setting)
 {
   g_return_if_fail (GTK_IS_LABEL (self));