Improve Tuya HVACMode handling (#158042)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

homeassistant/components/tuya/climate.py

@@ -476,23 +476,23 @@ class TuyaClimateEntity(TuyaEntity, ClimateEntity):
         return self._read_wrapper(self._target_humidity_wrapper)
 
     @property
-    def hvac_mode(self) -> HVACMode:
+    def hvac_mode(self) -> HVACMode | None:
         """Return hvac mode."""
-        # If the switch is off, hvac mode is off as well.
-        # Unless the switch doesn't exists of course...
+        # If the switch is off, hvac mode is off.
+        switch_status: bool | None
         if (switch_status := self._read_wrapper(self._switch_wrapper)) is False:
             return HVACMode.OFF
 
-        # If the mode is known and maps to an HVAC mode, return it.
-        if (mode := self._read_wrapper(self._hvac_mode_wrapper)) and (
-            hvac_mode := TUYA_HVAC_TO_HA.get(mode)
-        ):
-            return hvac_mode
+        # If we don't have a mode wrapper, return switch only mode.
+        if self._hvac_mode_wrapper is None:
+            if switch_status is True:
+                return self.entity_description.switch_only_hvac_mode
+            return None
 
-        # If hvac_mode is unknown, return the switch only mode.
-        if switch_status:
-            return self.entity_description.switch_only_hvac_mode
-        return HVACMode.OFF
+        # If we do have a mode wrapper, check if the mode maps to an HVAC mode.
+        if (hvac_status := self._read_wrapper(self._hvac_mode_wrapper)) is None:
+            return None
+        return TUYA_HVAC_TO_HA.get(hvac_status)
 
     @property
     def preset_mode(self) -> str | None:

tests/components/tuya/snapshots/test_climate.ambr

@@ -651,7 +651,7 @@
     'last_changed': <ANY>,
     'last_reported': <ANY>,
     'last_updated': <ANY>,
-    'state': 'off',
+    'state': 'unknown',
   })
 # ---
 # name: test_platform_setup_and_discovery[climate.itc_308_wifi_thermostat-entry]
@@ -713,7 +713,7 @@
     'last_changed': <ANY>,
     'last_reported': <ANY>,
     'last_updated': <ANY>,
-    'state': 'off',
+    'state': 'unknown',
   })
 # ---
 # name: test_platform_setup_and_discovery[climate.kabinet-entry]
@@ -1007,7 +1007,7 @@
     'last_changed': <ANY>,
     'last_reported': <ANY>,
     'last_updated': <ANY>,
-    'state': 'off',
+    'state': 'unknown',
   })
 # ---
 # name: test_platform_setup_and_discovery[climate.polotentsosushitel-entry]