PERF: Fix double check of is_empty in MultiPolygon() constructor (bec…

…ause truthiness implies that) (#1655)

Co-authored-by: Joris Van den Bossche <jorisvandenbossche@gmail.com>

shapely/geometry/multipolygon.py

@@ -55,11 +55,8 @@ def __new__(self, polygons=None):
             return polygons
 
         polygons = getattr(polygons, "geoms", polygons)
-        polygons = [
-            p
-            for p in polygons
-            if p and not (isinstance(p, polygon.Polygon) and p.is_empty)
-        ]
+        # remove None and empty polygons from list of Polygons
+        polygons = [p for p in polygons if p]
 
         L = len(polygons)
 

shapely/tests/geometry/test_multipolygon.py

@@ -67,6 +67,10 @@ def test_multipolygon(self):
             ]
         ]
 
+        # None and empty polygons are dropped
+        geom_from_list_with_empty = MultiPolygon([p, None, Polygon()])
+        assert geom_from_list_with_empty == geom
+
         # Or from a list of multiple polygons
         geom_multiple_from_list = MultiPolygon([p, p])
         assert len(geom_multiple_from_list.geoms) == 2