Undesired behavior of Redistribute and RedistributeV2

[mike76-dev]

I'm talking about an edge case where the SingleAddressWallet is ordered to redistribute the outputs of a wallet consisting of one single output (e.g. if that wallet was just created and funded with a single transaction).

If the desired number of outputs is greater than the batch size (e.g. 100 vs. 10), and there is only one output in the wallet, both Redistribute and RedistributeV2 create a set of identical transactions, each spending the same parent output.

Then, if the resulting transaction set is submitted to the TxPool, the whole set is rejected, because each transaction, except the very first one, double-spends the parent output, which has already been spent in the first transaction.

[mike76-dev]

I was able to work around with this code:

numOutputs := wantedOutputs
maxOutputs := len(utxos) * redistributeBatchSize // *10
if numOutputs > maxOutputs {
	numOutputs = maxOutputs
}

So, if you don't think that this edge case needs handling, please feel free to close the issue.

[mike76-dev]

Wait, something still isn't right.

Even with "enough" outputs (like, 11 out of 100 required), RedistributeV2 uses the same output in multiple transactions from the set, so the set is still bound to be rejected.