void test_from_ogc_filter()
    {
      QFETCH( QString, xmlText );
      QFETCH( QString, dumpText );

      QDomDocument doc;
      QVERIFY(doc.setContent(xmlText, true));
      QDomElement rootElem = doc.documentElement();

      QgsExpression* expr = QgsExpression::createFromOgcFilter( rootElem );
      QVERIFY( expr );

      qDebug("OGC XML  : %s", xmlText.toAscii().data() );
      qDebug("EXPR-DUMP: %s", expr->dump().toAscii().data() );

      if ( expr->hasParserError() )
        qDebug( "ERROR: %s ", expr->parserErrorString().toAscii().data() );
      QVERIFY( !expr->hasParserError() );

      QCOMPARE( dumpText, expr->dump() );

      delete expr;
    }
QgsFeatureRequest::QgsFeatureRequest( const QgsExpression& expr )
    : mFilter( FilterExpression )
    , mFilterExpression( new QgsExpression( expr.dump() ) )
    , mFlags( 0 )
{
}