signrawtransaction returns "complete" : false sometimes when it really is complete #2265

When doing offline signing of unknown txins with the scriptpubkey provided on the command line signrawtransaction returns complete false when the transaction is really completed.

If the txin is unknown, then how does signrawtransaction know that the signature for that scriptSig is correct?

I suppose it could assume that if there is a signature then it is correct... but that seems dangerous.

How about omitting the "complete" flag entirely, when it's not known? It could be supplemented with a count of signatures (and total signatures in transaction) if there's no other way to tell that info already.

An 'unknown' state of any kind would be fine— false is confusing though.

This issue is reported for txins unknown to bitcoin, i.e not in the mempool or blockchain, thus the scriptPubKey has to be provided explicitly.

The existing functional tests at wallet_signrawtransactionwithwallet.py, rpc_signrawtransactionwithkey.py are already checking against this behavior and what is reported seems to not be an issue anymore or it's reproduction is more complicated. I've also try to reproduce this manually on regtest but I still was not able to do so.

Note:

• The referenced signrawtransaction RPC was fully removed in v0.18. and since replaced with signrawtransactionwithkey and signrawtransactionwithwallet.
• Functional tests for this RPC were introduced much later with #5937

what is reported seems to not be an issue anymore or it's reproduction is more complicated.

Ok, I guess if it is not yet fixed, it can be reopened the next time someone has steps to reproduce.