public void TestCommonEdge() { Triangle firstTriangle = new Triangle(new Vector2(0, 0), new Vector2(1, 0), new Vector2(0, 3)); Triangle secondTriangle = new Triangle(new Vector2(0, 0), new Vector2(1, 0), new Vector2(0, -3)); List <Vector2> expected = new List <Vector2>() { firstTriangle.V0, firstTriangle.V1 }; var result = firstTriangle.CommonEdge(secondTriangle); Assert.AreEqual(expected, result); }