fixup! fixup! PR #200 finetune VectorCube.apply_dimension

Author: soxofaan

openeo_driver/datacube.py

@@ -520,8 +520,12 @@ def apply_dimension(
         if single_run_udf:
             # Process with single "run_udf" node
             if self._cube is None and dimension == self.DIM_GEOMETRIES and target_dimension is None:
+                log.warning(
+                    f"Using experimental feature: DriverVectorCube.apply_dimension along dim {dimension} and empty cube"
+                )
                 # TODO: this is non-standard special case: vector cube with only geometries, but no "cube" data
-                feature_collection = openeo.udf.FeatureCollection(id="_", data=self._as_geopandas_df())
+                gdf = self._as_geopandas_df()
+                feature_collection = openeo.udf.FeatureCollection(id="_", data=gdf)
                 udf_data = openeo.udf.UdfData(
                     proj={"EPSG": self._geometries.crs.to_epsg()},
                     feature_collection_list=[feature_collection],
@@ -537,8 +541,7 @@ def apply_dimension(
                         return DriverVectorCube(geometries=result_features[0].data)
                 raise ValueError(f"Could not handle UDF result: {result_data}")
 
-        else:
-            raise FeatureUnsupportedException()
+        raise FeatureUnsupportedException()