Implement Manager#flush

lib/uh/wm/manager.rb

@@ -35,6 +35,10 @@ module Uh
         @events.emit :disconnected
       end
 
+      def flush
+        @display.flush
+      end
+
       def grab_key keysym, mod = nil
         mod_mask = KEY_MODIFIERS[@modifier]
         mod_mask |= KEY_MODIFIERS[mod] if mod

spec/uh/wm/manager_spec.rb

@@ -82,6 +82,13 @@ module Uh
         end
       end
 
+      describe '#flush' do
+        it 'flushes the display' do
+          expect(display).to receive :flush
+          manager.flush
+        end
+      end
+
       describe '#grab_key' do
         it 'grabs given key on the display' do
           expect(manager.display)