diff --git a/tests/test_terrain.py b/tests/test_terrain.py
index 3a64fe52..834ab9db 100644
--- a/tests/test_terrain.py
+++ b/tests/test_terrain.py
@@ -91,7 +91,9 @@ def test_attribute_functions_against_gdaldem(self, attribute: str) -> None:
                 dem.data, resolution=dem.res, method="ZevenbergThorne", degrees=True
             ),
             "aspect_Zevenberg": lambda dem: xdem.terrain.aspect(dem.data, method="ZevenbergThorne", degrees=True),
-            "hillshade_Zevenberg": lambda dem: xdem.terrain.hillshade(dem.data, resolution=dem.res, method="ZevenbergThorne"),
+            "hillshade_Zevenberg": lambda dem: xdem.terrain.hillshade(
+                dem.data, resolution=dem.res, method="ZevenbergThorne"
+            ),
             "tri_Riley": lambda dem: xdem.terrain.terrain_ruggedness_index(dem.data, method="Riley"),
             "tri_Wilson": lambda dem: xdem.terrain.terrain_ruggedness_index(dem.data, method="Wilson"),
             "tpi": lambda dem: xdem.terrain.topographic_position_index(dem.data),