public void when_ContainsKey_that_does_not_exist_then_returns_false()
{
var dictionary = new NotNullDictionary<String, String>();
var result = dictionary.ContainsKey("foo");
Assert.IsFalse(result);
}
public void when_ContainsKey_that_exists_then_returns_true()
{
var dictionary = new NotNullDictionary<String, String>();
dictionary.Add("foo", "bar");
var result = dictionary.ContainsKey("foo");
Assert.IsTrue(result);
}