[set] add a test demonstrating a bug in hb_set_union.

1 files changed, 10 insertions, 0 deletions

diff --git a/test/api/test-set.c b/test/api/test-set.c
index 1c51e846..15958c57 100644
--- a/test/api/test-set.c
+++ b/test/api/test-set.c
@@ -137,10 +137,13 @@ test_set_algebra (void)
 {
   hb_set_t *s = hb_set_create ();
   hb_set_t *o = hb_set_create ();
+  hb_set_t *o2 = hb_set_create ();
 
   hb_set_add (o, 13);
   hb_set_add (o, 19);
 
+  hb_set_add (o2, 0x660E);
+
   test_empty (s);
   g_assert (!hb_set_is_equal (s, o));
   hb_set_set (s, o);
@@ -159,6 +162,13 @@ test_set_algebra (void)
 
   hb_set_clear (s);
   test_empty (s);
+  g_assert_cmpint (hb_set_get_population (s), ==, 0);
+  hb_set_union (s, o2);
+  g_assert_cmpint (hb_set_get_population (s), ==, 1);
+  g_assert (hb_set_has (s, 0x660E));
+
+  hb_set_clear (s);
+  test_empty (s);
   hb_set_add_range (s, 10, 17);
   g_assert (!hb_set_is_equal (s, o));
   hb_set_intersect (s, o);