LINQPad IPolygon2.QueryExteriorRingsEx crash test (ArcGIS 10.1 SP1)

polygonToLine.linq

<Query Kind="Program">
  <GACReference>ESRI.ArcGIS.Geometry, Version=10.1.0.0, Culture=neutral, PublicKeyToken=8fc3cc631e44ad86</GACReference>
  <GACReference>ESRI.ArcGIS.System, Version=10.1.0.0, Culture=neutral, PublicKeyToken=8fc3cc631e44ad86</GACReference>
  <GACReference>ESRI.ArcGIS.Version, Version=10.1.0.0, Culture=neutral, PublicKeyToken=8fc3cc631e44ad86</GACReference>
  <Namespace>ESRI.ArcGIS.esriSystem</Namespace>
  <Namespace>ESRI.ArcGIS.Geometry</Namespace>
</Query>

void Main()
{
    if (ESRI.ArcGIS.RuntimeManager.ActiveRuntime == null)
        ESRI.ArcGIS.RuntimeManager.BindLicense(ESRI.ArcGIS.ProductCode.EngineOrDesktop);

    var polygon1 = CreateSinglePartPolygon().Dump();
    var polygon2 = CreateDonutPolygon().Dump();
    var polygon3 = CreateMultiPartPolygon().Dump();
    PolygonRingsToPolylines(polygon1).Dump();
    PolygonRingsToPolylines(polygon2).Dump();
    PolygonRingsToPolylines(polygon3).Dump();
    QueryExteriorRingsExTest(polygon1).Dump();
    QueryExteriorRingsExTest(polygon2).Dump();
    QueryExteriorRingsExTest(polygon3).Dump();
}

private static IEnumerable<IRing> QueryExteriorRingsExTest(IPolygon polygon)
{
    var polygon2 = (IPolygon2)polygon;
    IRing exteriorRings;
    polygon2.QueryExteriorRingsEx(polygon2.ExteriorRingCount, out exteriorRings);
    for (int i = 0; i < polygon2.ExteriorRingCount; i++)
    {
        yield return exteriorRings;
    }
}

private static IEnumerable<IPolyline> PolygonRingsToPolylines(IPolygon polygon)
{
    var polygon4 = (IPolygon4)polygon;
    var exteriorRingGeometryBag = (IGeometryBag)polygon4.ExteriorRingBag;
    var exteriorRingGeometryCollection = (IGeometryCollection)exteriorRingGeometryBag;
    for (int i = 0; i < exteriorRingGeometryCollection.GeometryCount; i++)
    {
        var exteriorRingGeometry = exteriorRingGeometryCollection.get_Geometry(i);
        yield return SegmentCollectionToPolyline((ISegmentCollection)exteriorRingGeometry);

        var interiorRingGeometryBag = polygon4.get_InteriorRingBag((IRing)exteriorRingGeometry);
        var interiorRingGeometryCollection = (IGeometryCollection)interiorRingGeometryBag;
        for (int j = 0; j < interiorRingGeometryCollection.GeometryCount; j++)
        {
            var interiorRingGeometry = interiorRingGeometryCollection.get_Geometry(i);
            yield return SegmentCollectionToPolyline((ISegmentCollection)interiorRingGeometry);
        }
    }
}

private static IPolyline SegmentCollectionToPolyline(ISegmentCollection segmentCollection)
{
    var polyline = (IPolyline)new PolylineClass();
    var geomcoll = (IGeometryCollection)polyline;
    var pathcoll = (ISegmentCollection)new PathClass();
    for (int i = 0; i < segmentCollection.SegmentCount; i++)
    {
        var segment = segmentCollection.get_Segment(i);
        pathcoll.AddSegment(segment);
    }
    geomcoll.AddGeometry((IGeometry)pathcoll);
    geomcoll.GeometriesChanged();
    return polyline;
}

private static IPolygon CreateSinglePartPolygon()
{
    var polygon = (IPolygon)new PolygonClass();
    var pointcoll = (IPointCollection4)polygon;
    var geometryBridge2 = (IGeometryBridge2)new GeometryEnvironmentClass();
    var aWKSPointBuffer = new WKSPoint[5];

    // Exterior ring
    aWKSPointBuffer[0].X = 0;
    aWKSPointBuffer[0].Y = 0;
    aWKSPointBuffer[1].X = 0;
    aWKSPointBuffer[1].Y = 1;
    aWKSPointBuffer[2].X = 1;
    aWKSPointBuffer[2].Y = 1;
    aWKSPointBuffer[3].X = 1;
    aWKSPointBuffer[3].Y = 0;
    aWKSPointBuffer[4].X = 0;
    aWKSPointBuffer[4].Y = 0;
    geometryBridge2.AddWKSPoints(pointcoll, ref aWKSPointBuffer);

    var topoOp = (ITopologicalOperator2)polygon;
    topoOp.IsKnownSimple_2 = false;
    topoOp.Simplify();
    return polygon;
}

private static IPolygon CreateDonutPolygon()
{
    var polygon = (IPolygon)new PolygonClass();
    var pointcoll = (IPointCollection4)polygon;
    var geometryBridge2 = (IGeometryBridge2)new GeometryEnvironmentClass();
    var aWKSPointBuffer = new WKSPoint[5];

    // Exterior ring
    aWKSPointBuffer[0].X = 0;
    aWKSPointBuffer[0].Y = 0;
    aWKSPointBuffer[1].X = 0;
    aWKSPointBuffer[1].Y = 4;
    aWKSPointBuffer[2].X = 4;
    aWKSPointBuffer[2].Y = 4;
    aWKSPointBuffer[3].X = 4;
    aWKSPointBuffer[3].Y = 0;
    aWKSPointBuffer[4].X = 0;
    aWKSPointBuffer[4].Y = 0;
    geometryBridge2.AddWKSPoints(pointcoll, ref aWKSPointBuffer);

    // Interior ring
    aWKSPointBuffer[0].X = 1;
    aWKSPointBuffer[0].Y = 1;
    aWKSPointBuffer[1].X = 3;
    aWKSPointBuffer[1].Y = 1;
    aWKSPointBuffer[2].X = 3;
    aWKSPointBuffer[2].Y = 3;
    aWKSPointBuffer[3].X = 1;
    aWKSPointBuffer[3].Y = 3;
    aWKSPointBuffer[4].X = 1;
    aWKSPointBuffer[4].Y = 1;
    geometryBridge2.AddWKSPoints(pointcoll, ref aWKSPointBuffer);

    var topoOp = (ITopologicalOperator2)polygon;
    topoOp.IsKnownSimple_2 = false;
    topoOp.Simplify();
    return polygon;
}

private static IPolygon CreateMultiPartPolygon()
{
    var polygon = (IPolygon)new PolygonClass();
    var pointcoll = (IPointCollection4)polygon;
    var geometryBridge2 = (IGeometryBridge2)new GeometryEnvironmentClass();
    var aWKSPointBuffer = new WKSPoint[5];

    // Exterior ring 1
    aWKSPointBuffer[0].X = 0;
    aWKSPointBuffer[0].Y = 0;
    aWKSPointBuffer[1].X = 0;
    aWKSPointBuffer[1].Y = 1;
    aWKSPointBuffer[2].X = 1;
    aWKSPointBuffer[2].Y = 1;
    aWKSPointBuffer[3].X = 1;
    aWKSPointBuffer[3].Y = 0;
    aWKSPointBuffer[4].X = 0;
    aWKSPointBuffer[4].Y = 0;
    geometryBridge2.AddWKSPoints(pointcoll, ref aWKSPointBuffer);

    // Exterior ring 2
    aWKSPointBuffer[0].X = 2;
    aWKSPointBuffer[0].Y = 2;
    aWKSPointBuffer[1].X = 2;
    aWKSPointBuffer[1].Y = 3;
    aWKSPointBuffer[2].X = 3;
    aWKSPointBuffer[2].Y = 3;
    aWKSPointBuffer[3].X = 3;
    aWKSPointBuffer[3].Y = 2;
    aWKSPointBuffer[4].X = 2;
    aWKSPointBuffer[4].Y = 2;
    geometryBridge2.AddWKSPoints(pointcoll, ref aWKSPointBuffer);

    var topoOp = (ITopologicalOperator2)polygon;
    topoOp.IsKnownSimple_2 = false;
    topoOp.Simplify();
    return polygon;
}