public void GetPerimeterTest_nullArray()
        {
            IGeometricalThings[] geoThingsTest = null;
            var geoCal = new GeometricalCalculator();

            var actual   = geoCal.GetPerimeter(geoThingsTest);
            var expected = 0;

            Assert.AreEqual(expected, actual);
        }
        public void GetPerimeterTest_5_2__1()
        {
            var geoThingsTest = new IGeometricalThings[]
            {
                new Triangle(5),
                new Square(2),
                new Circle(-1)
            };
            var geoCal = new GeometricalCalculator();


            var actual   = geoCal.GetPerimeter(geoThingsTest);
            var expected = 0;

            Assert.AreEqual(expected, actual);
        }