Choropleth does not reset selection

[janezd]

Geo version: 0.3.2-dev
Orange version: 3.33-dev

Actual behavior

Choropleth seems to not reset selection upon receiving new data.

Steps to reproduce the behavior

The way I encountered this:

• do hierarchical clustering, output result to choropleth,
• in clustering, select all clusters,
• in choroplet, select one region
• in clustering, select one small cluster, e.g. two points (if this does not crash, change selection).

Crashes with

  File "/Users/janez/dev/orange3-geo/orangecontrib/geo/widgets/owchoropleth.py", line 776, in apply_selection
    selection[index_group[0]] = index_group[1]
IndexError: index 159 is out of bounds for axis 0 with size 6

Notes

On the first glance, set_data should reset selection (it doesn't). On the second, reset may belong inside

        if not (data_existed and self.data is not None and
                array_equal(effective_data.X, self.effective_data.X)):

But the proper approach is probably to remove from selection all regions that no longer appear in the data.