mutte

src/textual/dom.py

@@ -237,6 +237,19 @@ def set_reactive(
             )
         setattr(self, f"_reactive_{reactive.name}", value)
 
+    def mutate_reactive(self, reactive: Reactive[ReactiveType]) -> None:
+        """Force an update to a mutable reactive.
+
+        This will invoke any associated watchers.
+
+        Args:
+            reactive (_type_): _description_
+        """
+
+        internal_name = f"_reactive_{reactive.name}"
+        value = getattr(self, internal_name)
+        reactive._set(self, value)
+
     def data_bind(
         self,
         *reactives: Reactive[Any],

src/textual/reactive.py

@@ -262,7 +262,7 @@ def __get__(
         else:
             return getattr(obj, internal_name)
 
-    def __set__(self, obj: Reactable, value: ReactiveType) -> None:
+    def _set(self, obj: Reactable, value: ReactiveType, always: bool = False) -> None:
         _rich_traceback_omit = True
 
         if not hasattr(obj, "_id"):
@@ -287,7 +287,7 @@ def __set__(self, obj: Reactable, value: ReactiveType) -> None:
         if callable(public_validate_function):
             value = public_validate_function(value)
         # If the value has changed, or this is the first time setting the value
-        if current_value != value or self._always_update:
+        if always or current_value != value or self._always_update:
             # Store the internal value
             setattr(obj, self.internal_name, value)
 
@@ -308,6 +308,11 @@ def __set__(self, obj: Reactable, value: ReactiveType) -> None:
                     recompose=self._recompose,
                 )
 
+    def __set__(self, obj: Reactable, value: ReactiveType) -> None:
+        _rich_traceback_omit = True
+
+        self._set(obj, value)
+
     @classmethod
     def _check_watchers(cls, obj: Reactable, name: str, old_value: Any) -> None:
         """Check watchers, and call watch methods / computes