[gtksourceview] Test UndoManager performances

[Sébastien Wilmet <swilmet src gnome org>]

commit 0a3d0399dc49eaeddfcf037517d128deef252d35
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Tue Sep 9 18:37:58 2014 +0200

    Test UndoManager performances
    
    And the results are....
    
    Old implementation based on a GPtrArray:
    Undo/Redo 10000 actions: 0.486454 seconds.
    Undo/Redo 100000 actions: 4.822937 seconds.
    
    New implementation based on GQueues (see next commits):
    Undo/Redo 10000 actions: 0.494246 seconds.
    Undo/Redo 100000 actions: 4.903951 seconds.
    
    So the difference is small, it's linear with the number of undo's, which
    means that an undo or redo is a O(1) operation. It was not the case with
    the older implementation based on GList, because GList was not used
    correctly (g_list_nth() was called on each undo or redo, because the
    location in the history was not stored with a GList node, but with a
    gint index).

 tests/Makefile.am                      |    3 +
 tests/test-undo-manager-performances.c |  104 ++++++++++++++++++++++++++++++++
 2 files changed, 107 insertions(+), 0 deletions(-)
---
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 003d2fc..a7532a0 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -52,6 +52,9 @@ test_search_LDADD =                                           \
 TEST_PROGS += test-search-performances
 test_search_performances_SOURCES = test-search-performances.c
 
+TEST_PROGS += test-undo-manager-performances
+test_undo_manager_performances_SOURCES = test-undo-manager-performances.c
+
 TEST_PROGS += test-widget
 test_widget_SOURCES = test-widget.c
 nodist_test_widget_SOURCES = test-widget-resources.c
diff --git a/tests/test-undo-manager-performances.c b/tests/test-undo-manager-performances.c
new file mode 100644
index 0000000..c08a6af
--- /dev/null
+++ b/tests/test-undo-manager-performances.c
@@ -0,0 +1,104 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8; coding: utf-8 -*- */
+/* test-undo-manager-performances.c
+ * This file is part of GtkSourceView
+ *
+ * Copyright (C) 2014 - Sébastien Wilmet <swilmet gnome org>
+ *
+ * GtkSourceView is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * GtkSourceView is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <gtksourceview/gtksource.h>
+
+#define NB_LINES 100000
+
+/* Returns the number of undo's. */
+static gint
+test_undo_redo (GtkSourceBuffer *buffer,
+               gint             max_actions)
+{
+       gint nb_actions;
+       gint i;
+
+       for (nb_actions = 0; nb_actions < max_actions; nb_actions++)
+       {
+               if (gtk_source_buffer_can_undo (buffer))
+               {
+                       gtk_source_buffer_undo (buffer);
+               }
+               else
+               {
+                       break;
+               }
+       }
+
+       for (i = 0; i < nb_actions; i++)
+       {
+               g_assert (gtk_source_buffer_can_redo (buffer));
+               gtk_source_buffer_redo (buffer);
+       }
+
+       return nb_actions;
+}
+
+gint
+main (gint    argc,
+      gchar **argv)
+{
+       GtkSourceBuffer *source_buffer;
+       GtkTextBuffer *text_buffer;
+       GtkTextIter iter;
+       GTimer *timer;
+       gint nb_actions;
+       gint i;
+
+       gtk_init (&argc, &argv);
+
+       source_buffer = gtk_source_buffer_new (NULL);
+       text_buffer = GTK_TEXT_BUFFER (source_buffer);
+
+       gtk_text_buffer_get_start_iter (text_buffer, &iter);
+
+       for (i = 0; i < NB_LINES; i++)
+       {
+               gtk_text_buffer_begin_user_action (text_buffer);
+
+               gtk_text_buffer_insert (text_buffer,
+                                       &iter,
+                                       "A line of text to fill the text buffer. Is it long enough?\n",
+                                       -1);
+
+               gtk_text_buffer_end_user_action (text_buffer);
+       }
+
+       timer = g_timer_new ();
+       nb_actions = test_undo_redo (source_buffer, NB_LINES / 10);
+       g_timer_stop (timer);
+
+       g_print ("Undo/Redo %d actions: %lf seconds.\n",
+                nb_actions,
+                g_timer_elapsed (timer, NULL));
+
+       g_timer_start (timer);
+       nb_actions = test_undo_redo (source_buffer, NB_LINES);
+       g_timer_stop (timer);
+
+       g_print ("Undo/Redo %d actions: %lf seconds.\n",
+                nb_actions,
+                g_timer_elapsed (timer, NULL));
+
+       g_object_unref (source_buffer);
+       g_timer_destroy (timer);
+       return 0;
+}