Ensure MQTT subscriptions can be made when the broker is disconnected (…

…#132270)

homeassistant/components/mqtt/client.py

@@ -227,7 +227,7 @@ def async_subscribe_internal(
             translation_placeholders={"topic": topic},
         ) from exc
     client = mqtt_data.client
-    if not client.connected and not mqtt_config_entry_enabled(hass):
+    if not mqtt_config_entry_enabled(hass):
         raise HomeAssistantError(
             f"Cannot subscribe to topic '{topic}', MQTT is not enabled",
             translation_key="mqtt_not_setup_cannot_subscribe",

tests/components/mqtt/test_client.py

@@ -1045,10 +1045,17 @@ async def test_restore_subscriptions_on_reconnect(
     mqtt_client_mock.reset_mock()
     mqtt_client_mock.on_disconnect(None, None, 0)
 
+    # Test to subscribe orther topic while the client is not connected
+    await mqtt.async_subscribe(hass, "test/other", record_calls)
+    async_fire_time_changed(hass, utcnow() + timedelta(seconds=3))  # cooldown
+    assert ("test/other", 0) not in help_all_subscribe_calls(mqtt_client_mock)
+
     mock_debouncer.clear()
     mqtt_client_mock.on_connect(None, None, None, 0)
     await mock_debouncer.wait()
+    # Assert all subscriptions are performed at the broker
     assert ("test/state", 0) in help_all_subscribe_calls(mqtt_client_mock)
+    assert ("test/other", 0) in help_all_subscribe_calls(mqtt_client_mock)
 
 
 @pytest.mark.parametrize(