private static IEnumerable<IPackage> GetPackageDependencies(IPackage package, IPackageRepository localRepository, IPackageRepository sourceRepository)
{
var walker = new InstallWalker(
localRepository,
sourceRepository,
new FrameworkName(".NET Framework, Version=4.0"),
NullLogger.Instance,
ignoreDependencies: false,
allowPrereleaseVersions: true);
return (from operation in walker.ResolveOperations(package)
where operation.Action == PackageAction.Install
select operation.Package);
}