Don't crash when calculating centroid of empty geometry

Refs #38983
qgis · Jun 10, 2021 · 9059cda · 9059cda
1 parent 73a4948
commit 9059cda
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Showing 2 changed files with 9 additions and 2 deletions.
diff --git a/src/core/geometry/qgsabstractgeometry.cpp b/src/core/geometry/qgsabstractgeometry.cpp
@@ -199,6 +199,9 @@ json QgsAbstractGeometry::asJsonObject( int precision ) const
 
 QgsPoint QgsAbstractGeometry::centroid() const
 {
+  if ( isEmpty() )
+    return QgsPoint();
+
   // http://en.wikipedia.org/wiki/Centroid#Centroid_of_polygon
   // Pick the first ring of first part for the moment
 

diff --git a/tests/src/core/testqgsgeometry.cpp b/tests/src/core/testqgsgeometry.cpp
@@ -2589,7 +2589,7 @@ void TestQgsGeometry::circularString()
 
   //centroid
   QgsCircularString l34;
-  QCOMPARE( l34.centroid(), QgsPoint( 0, 0 ) );
+  QCOMPARE( l34.centroid(), QgsPoint() );
   l34.setPoints( QgsPointSequence() << QgsPoint( 5, 10 ) );
   QCOMPARE( l34.centroid(), QgsPoint( 5, 10 ) );
   l34.setPoints( QgsPointSequence() << QgsPoint( 0, 0 ) << QgsPoint( 20, 10 ) << QgsPoint( 2, 9 ) );
@@ -11995,7 +11995,7 @@ void TestQgsGeometry::compoundCurve()
   //centroid
   QgsCircularString l34;
   QgsCompoundCurve c34;
-  QCOMPARE( c34.centroid(), QgsPoint( 0, 0 ) );
+  QCOMPARE( c34.centroid(), QgsPoint() );
   l34.setPoints( QgsPointSequence() << QgsPoint( 5, 10 ) );
   c34.addCurve( l34.clone() );
   QCOMPARE( c34.centroid(), QgsPoint( 5, 10 ) );
@@ -15829,6 +15829,10 @@ void TestQgsGeometry::multiPolygon()
   QVERIFY( dn1.removeDuplicateNodes( 0.001, false ) );
   QVERIFY( !dn1.removeDuplicateNodes( 0.001, false ) );
   QCOMPARE( dn1.asWkt(), QStringLiteral( "MultiPolygonZ (((0 0 0, 10 10 0, 11 9 0, 9 8 0, 1 -1 0, 0 0 0)),((7 -1 0, 12 7 0, 13 6 0, 8 -3 0, 7 -1 0)))" ) );
+
+  // test centroid of empty multipolygon
+  QgsMultiPolygon empty;
+  QCOMPARE( empty.centroid().asWkt(), QStringLiteral( "Point EMPTY" ) );
 }
 
 void TestQgsGeometry::geometryCollection()