Exclude relations with invalid multipolygon geometry (#564)

planetiler-core/src/main/java/com/onthegomap/planetiler/reader/osm/OsmReader.java

@@ -293,7 +293,8 @@ public class OsmReader implements Closeable, MemoryEstimator.HasEstimate {
   }
 
   private static boolean isMultipolygon(OsmElement.Relation relation) {
-    return relation.hasTag("type", "multipolygon", "boundary", "land_area");
+    return relation.hasTag("type", "multipolygon", "boundary", "land_area") &&
+      relation.members().stream().anyMatch(m -> m.type() == OsmElement.Type.WAY);
   }
 
   /**

planetiler-core/src/test/java/com/onthegomap/planetiler/reader/osm/OsmReaderTest.java

@@ -1,10 +1,7 @@
 package com.onthegomap.planetiler.reader.osm;
 
 import static com.onthegomap.planetiler.TestUtils.*;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 
 import com.onthegomap.planetiler.Profile;
 import com.onthegomap.planetiler.TestUtils;
@@ -542,6 +539,52 @@ class OsmReaderTest {
     );
   }
 
+
+  @Test
+  void testMultipolygonInvalidMembers() {
+    OsmReader reader = newOsmReader();
+
+    var relation = new OsmElement.Relation(16);
+
+    var childRelation = new OsmElement.Relation(17);
+    var childNode = new OsmElement.Node(17, 0.0, 0.0);
+
+    relation.setTag("type", "multipolygon");
+    relation.members().add(new OsmElement.Relation.Member(OsmElement.Type.RELATION, childRelation.id(), "outer"));
+    relation.members().add(new OsmElement.Relation.Member(OsmElement.Type.NODE, childNode.id(), "inner"));
+
+    List<OsmElement> elements = List.of(
+      node(1, 0.1, 0.1),
+      node(2, 0.9, 0.1),
+      node(3, 0.9, 0.9),
+      node(4, 0.1, 0.9),
+
+      node(5, 0.2, 0.3),
+      node(6, 0.8, 0.3),
+      node(7, 0.8, 0.8),
+      node(8, 0.2, 0.8),
+
+      node(9, 0.2, 0.2),
+      node(10, 0.8, 0.2),
+      node(11, 0.8, 0.7),
+      node(12, 0.2, 0.7),
+
+      childNode,
+      childRelation,
+
+      relation
+    );
+
+    processPass1Block(reader, elements);
+    elements.stream().flatMap(nodes).forEach(reader::processNodePass2);
+    var nodeCache = reader.newNodeLocationProvider();
+    elements.stream().flatMap(ways).forEach(way -> reader.processWayPass2(way, nodeCache));
+
+    var feature = reader.processRelationPass2(relation, nodeCache);
+
+    assertNull(feature);
+  }
+
   @Test
   void testMultiPolygonRefersToNonexistentNode() {
     OsmReader reader = newOsmReader();