@Test
 public void detectWithIfNone() {
   ImmutableBag<String> immutableStrings = this.newBag();
   Assert.assertEquals(
       "1",
       immutableStrings.detectWithIfNone(
           Object::equals, "1", new PassThruFunction0<String>("Not Found")));
   Assert.assertEquals(
       "Not Found",
       immutableStrings.detectWithIfNone(
           Object::equals, "10000", new PassThruFunction0<String>("Not Found")));
 }