Fix bug in state trigger when using for: without to: (#40556)

homeassistant/components/homeassistant/triggers/state.py

@@ -145,7 +145,7 @@ async def async_attach_trigger(
             else:
                 cur_value = new_st.attributes.get(attribute)
 
-            if CONF_TO not in config:
+            if CONF_FROM in config and CONF_TO not in config:
                 return cur_value != old_value
 
             return cur_value == new_value

tests/components/homeassistant/triggers/test_state.py

@@ -538,6 +538,39 @@ async def test_if_fires_on_entity_change_with_for_without_to(hass, calls):
     assert len(calls) == 1
 
 
+async def test_if_does_not_fires_on_entity_change_with_for_without_to_2(hass, calls):
+    """Test for firing on entity change with for."""
+    assert await async_setup_component(
+        hass,
+        automation.DOMAIN,
+        {
+            automation.DOMAIN: {
+                "trigger": {
+                    "platform": "state",
+                    "entity_id": "test.entity",
+                    "for": {"seconds": 5},
+                },
+                "action": {"service": "test.automation"},
+            }
+        },
+    )
+    await hass.async_block_till_done()
+
+    utcnow = dt_util.utcnow()
+    with patch("homeassistant.core.dt_util.utcnow") as mock_utcnow:
+        mock_utcnow.return_value = utcnow
+
+        for i in range(10):
+            hass.states.async_set("test.entity", str(i))
+            await hass.async_block_till_done()
+
+            mock_utcnow.return_value += timedelta(seconds=1)
+            async_fire_time_changed(hass, mock_utcnow.return_value)
+            await hass.async_block_till_done()
+
+    assert len(calls) == 0
+
+
 async def test_if_fires_on_entity_creation_and_removal(hass, calls):
     """Test for firing on entity creation and removal, with to/from constraints."""
     # set automations for multiple combinations to/from