private BuildStep tryFillEnumerableOfAllKnown(Type serviceType)
{
var elementType = EnumerableStep.DetermineElementType(serviceType);
var all = _graph.FindAll(elementType);
if (!all.All(x => _graph.CanResolve(x)))
{
return(null);
}
var childSteps = all.Select(FindStep).ToArray();
return(new EnumerableStep(serviceType, childSteps));
}