[test] Extend hb_set test for issue 579 (currently failing)

test/api/test-set.c

@@ -188,6 +188,24 @@ test_set_algebra (void)
   g_assert (hb_set_has (o, 888));
   g_assert (hb_set_has (o, 889));
 
+  hb_set_clear (s);
+  test_empty (s);
+  hb_set_add_range (s, 886, 895);
+  hb_set_add (s, 1014);
+  hb_set_add (s, 1017);
+  hb_set_add (s, 1024);
+  hb_set_add (s, 1113);
+  hb_set_add (s, 1121);
+  g_assert_cmpint (hb_set_get_population (s), ==, 15);
+
+  hb_set_clear (o);
+  test_empty (o);
+  hb_set_add (o, 889);
+  g_assert_cmpint (hb_set_get_population (o), ==, 1);
+  hb_set_intersect (o, s);
+  g_assert_cmpint (hb_set_get_population (o), ==, 1);
+  g_assert (hb_set_has (o, 889));
+
   hb_set_destroy (s);
   hb_set_destroy (o);
 }