Struct NonDustDrainCoinSelection 

pub struct NonDustDrainCoinSelection;

Coin selection for transactions whose only output is the drain (change) output, like a CPFP child. Guarantees that this output ends up above the dust limit.

BDK’s default algorithm stops selecting coins as soon as the target amount is covered. If the selected coins overshoot the target by less than the dust limit, the leftover is too small to be a valid output. Normally BDK would drop it and let it go to fees, but when the drain is the transaction’s only output, dropping it leaves no outputs at all, so TxBuilder::finish fails with InsufficientFunds — even if the wallet has plenty of other coins available.

This wrapper asks the default algorithm for slightly more: the dust limit, plus the fee the drain output itself adds. That makes it keep pulling in coins until the leftover is a valid output. The result is then adjusted so that the extra ends up in the drain output rather than being burned as fee.

Trait Implementations

impl Clone for NonDustDrainCoinSelection

fn clone(&self) -> NonDustDrainCoinSelection

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl CoinSelectionAlgorithm for NonDustDrainCoinSelection

fn coin_select<R: RngCore>( &self, required_utxos: Vec<WeightedUtxo>, optional_utxos: Vec<WeightedUtxo>, fee_rate: FeeRate, target_amount: Amount, drain_script: &Script, rand: &mut R, ) -> Result<CoinSelectionResult, InsufficientFunds>

Perform the coin selection

impl Copy for NonDustDrainCoinSelection

impl Debug for NonDustDrainCoinSelection

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for NonDustDrainCoinSelection

fn default() -> NonDustDrainCoinSelection

Returns the “default value” for a type.