public void Register_ThrowsWhenChangesArePrevented()
{
var settingsHolder = new SettingsHolder();
var pipelineSettings = new PipelineSettings(settingsHolder);
pipelineSettings.PreventChanges();
Assert.Throws <InvalidOperationException>(() => pipelineSettings.Register(typeof(Behavior1), "newStep"));
Assert.Throws <InvalidOperationException>(() => pipelineSettings.Replace("newStep", typeof(Behavior1)));
}