public void Add_NewPrefix_WithNullValue_Works(params object[] prefix)
{
var sut = new PrefixDictionary <object, object>();
Assert.That(() => sut.Add(prefix, null), Throws.Nothing);
}
public void Add_NullPrefix_Throw()
{
var sut = new PrefixDictionary <char, object>();
Assert.That(() => sut.Add(null, 1), Throws.ArgumentNullException);
}