transaction.ts issue

[Brian]

I think in hasDuplicates() function: const groups = _.countBy(txIns, (txIn) => txIn.txOutId + txIn.txOutId);
Why we need calculate txIn.txOutId two time?
I think it should be: const groups = _.countBy(txIns, (txIn) => txIn.txOutId + txIn.txOutIndex);