// QueryUtils' reader with a fake cache key, so insanity checker cannot walk
// along our reader:
if (r instanceof AtomicReader) {
r = new AssertingAtomicReader((AtomicReader)r);
} else if (r instanceof DirectoryReader) {
r = new AssertingDirectoryReader((DirectoryReader)r);
}
break;
default:
fail("should not get here");
}