Add significant change helper check_valid_float (#106005)

homeassistant/helpers/significant_change.py

@@ -147,6 +147,15 @@ def check_percentage_change(
     return _check_numeric_change(old_state, new_state, change, percentage_change)
 
 
+def check_valid_float(value: str | int | float) -> bool:
+    """Check if given value is a valid float."""
+    try:
+        float(value)
+    except ValueError:
+        return False
+    return True
+
+
 class SignificantlyChangedChecker:
     """Class to keep track of entities to see if they have significantly changed.
 

tests/helpers/test_significant_change.py

@@ -72,3 +72,14 @@ async def test_significant_change_extra(hass: HomeAssistant, checker) -> None:
         State(ent_id, "200", attrs), extra_arg=1
     )
     assert checker.async_is_significant_change(State(ent_id, "200", attrs), extra_arg=2)
+
+
+async def test_check_valid_float(hass: HomeAssistant) -> None:
+    """Test extra significant checker works."""
+    assert significant_change.check_valid_float("1")
+    assert significant_change.check_valid_float("1.0")
+    assert significant_change.check_valid_float(1)
+    assert significant_change.check_valid_float(1.0)
+    assert not significant_change.check_valid_float("")
+    assert not significant_change.check_valid_float("invalid")
+    assert not significant_change.check_valid_float("1.1.1")