code: func diffTreeIsEquals(a, b noder.Hasher) bool {
  	hashA := a.Hash()
  	hashB := b.Hash()
  
  	if bytes.Equal(hashA, emptyNoderHash) || bytes.Equal(hashB, emptyNoderHash) {
  		return false
  	}
  
  	return bytes.Equal(hashA, hashB)
  }
docs: // diffTreeIsEquals is a implementation of noder.Equals, used to compare
  // noder.Noder, it compare the content and the length of the hashes.
  //
  // Since some of the noder.Noder implementations doesn't compute a hash for
  // some directories, if any of the hashes is a 24-byte slice of zero values
  // the comparison is not done and the hashes are take as different.