RT #125611: basic test for Set subclassability
RT #125611: basic test for Set subclassability

dankogai/roast,bitrauser/roast,b2gills/roast,dogbert17/roast,dogbert17/roast,cygx/roast,cygx/roast,b2gills/roast,niner/roast,bitrauser/roast,zostay/roast,dankogai/roast,cygx/roast,niner/roast,laben/roast,skids/roast,skids/roast,niner/roast,zostay/roast,laben/roast,skids/roast,laben/roast,dankogai/roast,zostay/roast,b2gills/roast,perl6/roast