internal RuntimeMetadataReferenceResolver( RelativePathResolver pathResolver, NuGetPackageResolver packageResolver, GacFileResolver gacFileResolver, Func <string, MetadataReferenceProperties, PortableExecutableReference> fileReferenceProvider = null) { PathResolver = pathResolver; PackageResolver = packageResolver; GacFileResolver = gacFileResolver; _fileReferenceProvider = fileReferenceProvider ?? new Func <string, MetadataReferenceProperties, PortableExecutableReference>((path, properties) => MetadataReference.CreateFromFile(path, properties)); }