private string[] ExpandFiles(string @base, IList<object> files)
{
var matcher = CreateMatcher();
var fullFiles = files.Select(f => _pathHelper.MakeFull(@base, f.ToString()));
var glob = new Glob(fullFiles);
var result = glob.Execute(new DirectoryInfoWrapper(
new DirectoryInfo(_env.ContentRootPath)));
return result.Files
.Select(f => Path.Combine(_env.ContentRootPath, f.Path))
.Select(f => _pathHelper.MakeRelative(f))
.Where(f => _pathHelper.FileExists(f)).ToArray();
}