Expose count_covered in moving window

Signed-off-by: cwasicki <[email protected]>

Author: cwasicki

src/frequenz/sdk/timeseries/_moving_window.py

@@ -315,6 +315,15 @@ def count_valid(self) -> int:
         """
         return self._buffer.count_valid()
 
+    def count_covered(self) -> int:
+        """Count the number of samples that are covered by the oldest and newest valid samples.
+
+        Returns:
+            The count of samples between the oldest and newest (inclusive) valid samples
+                or 0 if there are is no time range covered.
+        """
+        return self._buffer.count_covered()
+
     @overload
     def __getitem__(self, key: SupportsIndex) -> float:
         """See the main __getitem__ method.

tests/timeseries/test_moving_window.py

@@ -144,12 +144,15 @@ async def test_window_size() -> None:
     async with window:
         assert window.capacity == 5, "Wrong window capacity"
         assert window.count_valid() == 0, "Window should be empty"
+        assert window.count_covered() == 0, "Window should be empty"
         await push_logical_meter_data(sender, range(0, 2))
         assert window.capacity == 5, "Wrong window capacity"
         assert window.count_valid() == 2, "Window should be partially full"
+        assert window.count_covered() == 2, "Window should be partially full"
         await push_logical_meter_data(sender, range(2, 20))
         assert window.capacity == 5, "Wrong window capacity"
         assert window.count_valid() == 5, "Window should be full"
+        assert window.count_covered() == 5, "Window should be full"
 
 
 # pylint: disable=redefined-outer-name