Fix filterVertices for multipoint geometries

Author: nyalldawson

src/core/geometry/qgsmultipoint.cpp

@@ -182,6 +182,20 @@ double QgsMultiPoint::segmentLength( QgsVertexId ) const
   return 0.0;
 }
 
+void QgsMultiPoint::filterVertices( const std::function<bool ( const QgsPoint & )> &filter )
+{
+  mGeometries.erase( std::remove_if( mGeometries.begin(), mGeometries.end(), // clazy:exclude=detaching-member
+                                     [&filter]( const QgsAbstractGeometry * part )
+  {
+    if ( const QgsPoint *point = qgsgeometry_cast< const QgsPoint * >( part ) )
+    {
+      return !filter( *point );
+    }
+    else
+      return true;
+  } ), mGeometries.end() ); // clazy:exclude=detaching-member
+}
+
 bool QgsMultiPoint::wktOmitChildType() const
 {
   return true;

src/core/geometry/qgsmultipoint.h

@@ -47,6 +47,7 @@ class CORE_EXPORT QgsMultiPoint: public QgsGeometryCollection
     double segmentLength( QgsVertexId startVertex ) const override;
 
 #ifndef SIP_RUN
+    void filterVertices( const std::function< bool( const QgsPoint & ) > &filter ) override;
 
     /**
      * Cast the \a geom to a QgsLineString.

tests/src/core/testqgsgeometry.cpp

@@ -4538,7 +4538,7 @@ void TestQgsGeometry::lineString()
   filterLine.filterVertices( filter ); // no crash
   filterLine.setPoints( QgsPointSequence()  << QgsPoint( 11, 2, 3, 4, QgsWkbTypes::PointZM ) << QgsPoint( 1, 2, 3, 4, QgsWkbTypes::PointZM ) << QgsPoint( 4, 12, 13, 14, QgsWkbTypes::PointZM ) << QgsPoint( 111, 12, 23, 24, QgsWkbTypes::PointZM ) );
   filterLine.filterVertices( filter );
-  QCOMPARE( swapLine.asWkt( 2 ), QStringLiteral( "LineStringZM (2 11 3 4, 12 11 13 14, 12 111 23 24)" ) );
+  QCOMPARE( filterLine.asWkt( 2 ), QStringLiteral( "LineStringZM (1 2 3 4, 4 12 13 14)" ) );
 }
 
 void TestQgsGeometry::polygon()
@@ -11583,6 +11583,20 @@ void TestQgsGeometry::multiPoint()
   mp.addGeometry( new QgsPoint( QgsWkbTypes::PointZM, 10, 1, 4, 8 ) );
   QVERIFY( !mp.removeDuplicateNodes() );
   QCOMPARE( mp.numGeometries(), 2 );
+
+  // filter vertex
+  QgsMultiPoint filterPoint;
+  auto filter = []( const QgsPoint & point )-> bool
+  {
+    return point.x() < 5;
+  };
+  filterPoint.filterVertices( filter ); // no crash
+  filterPoint.addGeometry( new QgsPoint( QgsWkbTypes::PointZM, 10, 0, 4, 8 ) );
+  filterPoint.addGeometry( new QgsPoint( QgsWkbTypes::PointZM, 3, 0, 4, 8 ) );
+  filterPoint.addGeometry( new QgsPoint( QgsWkbTypes::PointZM, 1, 0, 4, 8 ) );
+  filterPoint.addGeometry( new QgsPoint( QgsWkbTypes::PointZM, 11, 0, 4, 8 ) );
+  filterPoint.filterVertices( filter );
+  QCOMPARE( filterPoint.asWkt( 2 ), QStringLiteral( "MultiPointZM ((3 0 4 8),(1 0 4 8))" ) );
 }
 
 void TestQgsGeometry::multiLineString()