public UnresolvedDependencyResult createUnresolvedDependency(ComponentSelector requested, ResolvedComponentResult from,
ComponentSelectionReason reason, ModuleVersionResolveException failure) {
List<Object> key = asList(requested, from);
if (!unresolvedDependencies.containsKey(key)) {
unresolvedDependencies.put(key, new DefaultUnresolvedDependencyResult(requested, reason, from, failure));
}
return unresolvedDependencies.get(key);
}