public void IndexOfAndContainsTest ()
{
DoubleCollection c = new Rectangle ().StrokeDashArray;
c.Add (1);
Assert.AreEqual (1, c.Count, "#1");
Assert.Throws<ArgumentException> (() => c.IndexOf (1), "#2");
Assert.Throws<ArgumentException> (() => c.Contains (1), "#3");
c.Insert (0, 2);
Assert.AreEqual (2.0, (double) c [0], "#4");
Assert.IsFalse (c.Remove (2), "#5");
Assert.AreEqual (2, c.Count, "#7");
Assert.AreEqual (2.0, (double) c [0], "#6");
}