/// <summary>Returns true if this single info is optimized (has no
/// pending norms or deletes, is in the same dir as the
/// writer, and matches the current compound file setting
/// </summary>
private bool IsOptimized(SegmentInfo info)
{
bool hasDeletions = writer.NumDeletedDocs(info) > 0;
return(!hasDeletions && !info.HasSeparateNorms() && info.dir == writer.GetDirectory() && info.GetUseCompoundFile() == useCompoundFile);
}