[gtk/test-text-buffer-undo] Add a test for text buffer history

[Matthias Clasen <matthiasc src gnome org>]

commit f5d34c054c03d8ee7b68bac103719761fad2a4bb
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed May 26 06:07:46 2021 -0400

    Add a test for text buffer history
    
    Check that things can be undone.

 testsuite/gtk/textbuffer.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
---
diff --git a/testsuite/gtk/textbuffer.c b/testsuite/gtk/textbuffer.c
index ff6d3c95f2..63be4e8e1d 100644
--- a/testsuite/gtk/textbuffer.c
+++ b/testsuite/gtk/textbuffer.c
@@ -1581,6 +1581,31 @@ test_get_iter (void)
   g_object_unref (buffer);
 }
 
+static void
+test_undo (void)
+{
+  GtkTextBuffer *buffer;
+
+  buffer = gtk_text_buffer_new (NULL);
+
+  g_assert_true (gtk_text_buffer_get_enable_undo (buffer));
+
+  gtk_text_buffer_set_text (buffer, "text before", -1);
+
+  gtk_text_buffer_begin_user_action (buffer);
+
+  gtk_text_buffer_insert_at_cursor (buffer, "add1", 4);
+  gtk_text_buffer_insert_at_cursor (buffer, "add2", 4);
+
+  gtk_text_buffer_end_user_action (buffer);
+
+  gtk_text_buffer_undo (buffer);
+
+  check_buffer_contents (buffer, "text before");
+
+  g_object_unref (buffer);
+}
+
 int
 main (int argc, char** argv)
 {
@@ -1600,6 +1625,7 @@ main (int argc, char** argv)
   g_test_add_func ("/TextBuffer/Tag", test_tag);
   g_test_add_func ("/TextBuffer/Clipboard", test_clipboard);
   g_test_add_func ("/TextBuffer/Get iter", test_get_iter);
+  g_test_add_func ("/TextBuffer/Undo", test_undo);
 
   return g_test_run();
 }