public void FlashKeep() { Flash flash = new Flash(); flash.Now("test1","hello"); flash.Now("test2","hello"); flash.Keep("test1"); flash.Sweep(); Assert.IsTrue( flash.ContainsKey("test1") ); Assert.IsFalse( flash.ContainsKey("test2") ); flash = new Flash(flash); flash.Sweep(); Assert.IsTrue( flash.Count == 0 ); flash.Now("test1","hello"); flash.Now("test2","hello"); flash.Keep(); flash.Sweep(); Assert.IsTrue( flash.ContainsKey("test1") ); Assert.IsTrue( flash.ContainsKey("test2") ); }