Handle template errors on MQTT payload handling (#110180)

* Handle template errors on MQTT payload handling (alt)

* Handle mqtt event en image template errors correctly

tests/components/mqtt/test_update.py

@@ -782,3 +782,40 @@ async def test_skipped_async_ha_write_state(
     """Test a write state command is only called when there is change."""
     await mqtt_mock_entry()
     await help_test_skipped_async_ha_write_state(hass, topic, payload1, payload2)
+
+
+VALUE_TEMMPLATES = {
+    "value_template": "state_topic",
+    "latest_version_template": "latest_version_topic",
+}
+
+
+@pytest.mark.parametrize(
+    "hass_config",
+    [
+        help_custom_config(
+            update.DOMAIN,
+            DEFAULT_CONFIG,
+            (
+                {
+                    state_topic: "test-topic",
+                    value_template: "{{ value_json.some_var * 1 }}",
+                },
+            ),
+        )
+        for value_template, state_topic in VALUE_TEMMPLATES.items()
+    ],
+    ids=VALUE_TEMMPLATES,
+)
+async def test_value_template_fails(
+    hass: HomeAssistant,
+    mqtt_mock_entry: MqttMockHAClientGenerator,
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    """Test the rendering of MQTT value template fails."""
+    await mqtt_mock_entry()
+    async_fire_mqtt_message(hass, "test-topic", '{"some_var": null }')
+    assert (
+        "TypeError: unsupported operand type(s) for *: 'NoneType' and 'int' rendering template"
+        in caplog.text
+    )