[hashmap] Add keys_ref() and values_ref()

src/hb-map.hh

@@ -301,6 +301,12 @@ struct hb_hashmap_t
     | hb_map (&item_t::key)
     | hb_map (hb_ridentity)
   )
+  auto keys_ref () const HB_AUTO_RETURN
+  (
+    + hb_array (items, mask ? mask + 1 : 0)
+    | hb_filter (&item_t::is_real)
+    | hb_map (&item_t::key)
+  )
   auto values () const HB_AUTO_RETURN
   (
     + hb_array (items, mask ? mask + 1 : 0)
@@ -308,6 +314,12 @@ struct hb_hashmap_t
     | hb_map (&item_t::value)
     | hb_map (hb_ridentity)
   )
+  auto values_ref () const HB_AUTO_RETURN
+  (
+    + hb_array (items, mask ? mask + 1 : 0)
+    | hb_filter (&item_t::is_real)
+    | hb_map (&item_t::value)
+  )
 
   /* Sink interface. */
   hb_hashmap_t& operator << (const hb_pair_t<K, V>& v)

src/test-map.cc

@@ -195,6 +195,11 @@ main (int argc, char **argv)
     m.get (hb::shared_ptr<hb_set_t> ());
     m.get (hb::shared_ptr<hb_set_t> (hb_set_get_empty ()));
     m.iter ();
+    m.keys ();
+    m.values ();
+    m.iter_ref ();
+    m.keys_ref ();
+    m.values_ref ();
   }
   /* Test hb::unique_ptr. */
   hb_hash (hb::unique_ptr<hb_set_t> ());
@@ -204,6 +209,8 @@ main (int argc, char **argv)
     m.get (hb::unique_ptr<hb_set_t> ());
     m.get (hb::unique_ptr<hb_set_t> (hb_set_get_empty ()));
     m.iter_ref ();
+    m.keys_ref ();
+    m.values_ref ();
   }
 
   return 0;