Fix attribute entity (#8066)

* Bugfix entity attribute setter

* Fix tests

* Fix tests part 2

* Change filter only None

* Fix tests part 3

* Update entity.py

* Fix tests

tests/components/switch/test_mqtt.py

@@ -35,7 +35,7 @@ class TestSensorMQTT(unittest.TestCase):
 
         state = self.hass.states.get('switch.test')
         self.assertEqual(STATE_OFF, state.state)
-        self.assertIsNone(state.attributes.get(ATTR_ASSUMED_STATE))
+        self.assertFalse(state.attributes.get(ATTR_ASSUMED_STATE))
 
         fire_mqtt_message(self.hass, 'state-topic', '1')
         self.hass.block_till_done()

tests/components/switch/test_rflink.py

@@ -59,7 +59,7 @@ def test_default_setup(hass, monkeypatch):
     switch_after_first_command = hass.states.get('switch.test')
     assert switch_after_first_command.state == 'on'
     # also after receiving first command state not longer has to be assumed
-    assert 'assumed_state' not in switch_after_first_command.attributes
+    assert not switch_after_first_command.attributes.get('assumed_state')
 
     # mock incoming command event for this device
     event_callback({

tests/components/switch/test_template.py

@@ -161,7 +161,7 @@ class TestTemplateSwitch:
         self.hass.block_till_done()
 
         state = self.hass.states.get('switch.test_template_switch')
-        assert 'icon' not in state.attributes
+        assert state.attributes.get('icon') == ''
 
         state = self.hass.states.set('switch.test_state', STATE_ON)
         self.hass.block_till_done()