If the user does not pass in outpoint data (for example if you use the blockchain.info api)
There are apis that consider coinbase to have tx_hash of null. If a user uses those api to generate a TransactionIn, the user will run into the problems.
This pull request checks for the existence of prev_out, and if a txin does not reference a txout, it will assign coinbase tx hash and tx index to it (which is 32 zero bytes and index of -1 or 0xffffffff)
If the user does not pass in outpoint data (for example if you use the blockchain.info api)
There are apis that consider coinbase to have tx_hash of null. If a user uses those api to generate a TransactionIn, the user will run into the problems.
This pull request checks for the existence of prev_out, and if a txin does not reference a txout, it will assign coinbase tx hash and tx index to it (which is 32 zero bytes and index of -1 or 0xffffffff)