[gtk/wip/otte/for-master: 1/3] filterlistmodel: Don't filter out every 513th element

[Benjamin Otte <otte src gnome org>]

commit 986f721938781edbc04f9a6fb83dc8f7263b2336
Author: Benjamin Otte <otte redhat com>
Date:   Thu Jul 9 22:22:04 2020 +0200

    filterlistmodel: Don't filter out every 513th element
    
    Incremental filtering would skip every 513th element due to an
    off-by-one error.
    
    Test included

 gtk/gtkfilterlistmodel.c        |  2 +-
 testsuite/gtk/filterlistmodel.c | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)
---
diff --git a/gtk/gtkfilterlistmodel.c b/gtk/gtkfilterlistmodel.c
index bd486bf9bf..a1a667190b 100644
--- a/gtk/gtkfilterlistmodel.c
+++ b/gtk/gtkfilterlistmodel.c
@@ -178,7 +178,7 @@ gtk_filter_list_model_run_filter (GtkFilterListModel *self,
     }
 
   if (more)
-    gtk_bitset_remove_range_closed (self->pending, 0, pos);
+    gtk_bitset_remove_range_closed (self->pending, 0, pos - 1);
   else
     g_clear_pointer (&self->pending, gtk_bitset_unref);
   g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_PENDING]);
diff --git a/testsuite/gtk/filterlistmodel.c b/testsuite/gtk/filterlistmodel.c
index 0e29cf501c..d0e55c57bf 100644
--- a/testsuite/gtk/filterlistmodel.c
+++ b/testsuite/gtk/filterlistmodel.c
@@ -88,6 +88,11 @@ add (GListStore *store,
   g_string_set_size (changes, 0); \
 }G_STMT_END
 
+#define ignore_changes(model) G_STMT_START{ \
+  GString *changes = g_object_get_qdata (G_OBJECT (model), changes_quark); \
+  g_string_set_size (changes, 0); \
+}G_STMT_END
+
 static GListStore *
 new_empty_store (void)
 {
@@ -345,6 +350,33 @@ test_change_filter (void)
   g_object_unref (filter);
 }
 
+static void
+test_incremental (void)
+{
+  GtkFilterListModel *filter;
+  GtkFilter *custom;
+  
+  /* everything is filtered */
+  filter = new_model (1000, is_larger_than, GUINT_TO_POINTER (10000));
+  gtk_filter_list_model_set_incremental (filter, TRUE);
+  assert_model (filter, "");
+  assert_changes (filter, "");
+
+  custom = gtk_custom_filter_new (is_near, GUINT_TO_POINTER (512), NULL);
+  gtk_filter_list_model_set_filter (filter, custom);
+  g_object_unref (custom);
+  assert_model (filter, "");
+  assert_changes (filter, "");
+
+  while (g_main_context_pending (NULL))
+    g_main_context_iteration (NULL, TRUE);
+  assert_model (filter, "510 511 512 513 514");
+  /* implementation detail */
+  ignore_changes (filter);
+
+  g_object_unref (filter);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -357,6 +389,7 @@ main (int argc, char *argv[])
   g_test_add_func ("/filterlistmodel/create", test_create);
   g_test_add_func ("/filterlistmodel/empty_set_filter", test_empty_set_filter);
   g_test_add_func ("/filterlistmodel/change_filter", test_change_filter);
+  g_test_add_func ("/filterlistmodel/incremental", test_incremental);
 
   return g_test_run ();
 }