Colinear self intersections not always reported

[esiegel]

Using version 2.0.0 this polygon will not report self intersection:

{ 
	type: 'Feature', 
  properties: {}, 
	geometry: { 
		type: 'Polygon',
		coordinates: [[
			[0,1],
			[1,1],
			[2,2],
			[1,1],
			[0,1]
		]]
	}
}

If i change one of the points, but it is still just as colinear, it does report self intersection

{ 
	type: 'Feature', 
  properties: {}, 
	geometry: { 
		type: 'Polygon',
		coordinates: [[
			[0,1],
			[1,1],
			[2,2],
			[1.5,1.5],
			[0,1]
		]]
	}
}