topology checker: catch difference error (fixes #7845)

qgis · Jul 21, 2013 · 454778c · 454778c
1 parent b4f282c
commit 454778c
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/src/plugins/topology/topolTest.cpp b/src/plugins/topology/topolTest.cpp
@@ -694,6 +694,11 @@ ErrorList topolTest::checkGaps( double tolerance, QgsVectorLayer *layer1, QgsVec
   //qDebug() << "extent wkt - " << bufferExtent->exportToWkt();
 
   QgsGeometry* diffGeoms = bufferExtent->difference( &test );
+  if ( !diffGeoms )
+  {
+    qDebug() << "difference result 0-";
+    return errorList;
+  }
 
   //qDebug() << "difference gometry - " << diffGeoms->exportToWkt() ;