Ignore false GSettings key change notifications

Similar to GObject::notify, the GSettings::changed can be emitted
even if a key didn't change. It's up to the user (aka evolution)
to test for real changes, thus let's do it. It may have certain
performance positive impact too.

3 files changed, 35 insertions, 3 deletions

diff --git a/modules/calendar/e-cal-shell-backend.c b/modules/calendar/e-cal-shell-backend.c
index 0a9c80fb3d..65f88022d8 100644
--- a/modules/calendar/e-cal-shell-backend.c
+++ b/modules/calendar/e-cal-shell-backend.c
@@ -666,7 +666,17 @@ static void
 cal_shell_backend_use_system_timezone_changed_cb (GSettings *settings,
                                                   const gchar *key)
 {
-	g_signal_emit_by_name (settings, "changed::timezone", timezone);
+	/* the '-1' is a trick to emit the change the first time */
+	static gint old_value = -1;
+	gboolean value;
+
+	value = g_settings_get_boolean (settings, key);
+
+	if ((value ? 1 : 0) != old_value) {
+		old_value = value ? 1 : 0;
+
+		g_signal_emit_by_name (settings, "changed::timezone", timezone);
+	}
 }
 
 static void
diff --git a/modules/calendar/e-task-shell-view-private.c b/modules/calendar/e-task-shell-view-private.c
index 863fd0136e..5a26284575 100644
--- a/modules/calendar/e-task-shell-view-private.c
+++ b/modules/calendar/e-task-shell-view-private.c
@@ -88,7 +88,21 @@ task_shell_view_hide_completed_tasks_changed_cb (GSettings *settings,
                                                  const gchar *key,
                                                  ETaskShellView *task_shell_view)
 {
-	task_shell_view_process_completed_tasks (task_shell_view);
+	GVariant *new_value, *old_value;
+
+	new_value = g_settings_get_value (settings, key);
+	old_value = g_hash_table_lookup (task_shell_view->priv->old_settings, key);
+
+	if (!new_value || !old_value || !g_variant_equal (new_value, old_value)) {
+		if (new_value)
+			g_hash_table_insert (task_shell_view->priv->old_settings, g_strdup (key), new_value);
+		else
+			g_hash_table_remove (task_shell_view->priv->old_settings, key);
+
+		task_shell_view_process_completed_tasks (task_shell_view);
+	} else if (new_value) {
+		g_variant_unref (new_value);
+	}
 }
 
 static void
@@ -210,6 +224,8 @@ task_shell_view_notify_view_id_cb (EShellView *shell_view)
 void
 e_task_shell_view_private_init (ETaskShellView *task_shell_view)
 {
+	task_shell_view->priv->old_settings = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, (GDestroyNotify) g_variant_unref);
+
 	e_signal_connect_notify (
 		task_shell_view, "notify::view-id",
 		G_CALLBACK (task_shell_view_notify_view_id_cb), NULL);
@@ -553,7 +569,11 @@ e_task_shell_view_private_dispose (ETaskShellView *task_shell_view)
 void
 e_task_shell_view_private_finalize (ETaskShellView *task_shell_view)
 {
-	/* XXX Nothing to do? */
+	if (task_shell_view->priv->old_settings) {
+		g_hash_table_destroy (task_shell_view->priv->old_settings);
+		task_shell_view->priv->old_settings = NULL;
+	}
+
 }
 
 void
diff --git a/modules/calendar/e-task-shell-view-private.h b/modules/calendar/e-task-shell-view-private.h
index b2a1511c9a..d29bd2e771 100644
--- a/modules/calendar/e-task-shell-view-private.h
+++ b/modules/calendar/e-task-shell-view-private.h
@@ -120,6 +120,8 @@ struct _ETaskShellViewPrivate {
 	guint update_completed_timeout;
 
 	guint confirm_purge : 1;
+
+	GHashTable *old_settings;
 };
 
 void		e_task_shell_view_private_init