Function gatherUtxos

packages/cashscript/test/test-util.ts:113–142

(
  utxos: Utxo[],
  options?: { amount?: bigint, fee?: bigint },
)

}

export function gatherUtxos(
  utxos: Utxo[],
  options?: { amount?: bigint, fee?: bigint },
): { utxos: Utxo[], total: bigint, changeAmount: bigint } {
  const targetUtxos: Utxo[] = [];
  let total = 0n;

  // 1000 for fees
  const { amount = 0n, fee = 1000n } = options ?? {};

  const minChangeAmount = 1000n;

  for (const utxo of utxos) {
    if (total - fee - minChangeAmount > amount) break;
    total += utxo.satoshis;
    targetUtxos.push(utxo);
  }

  const changeAmount = total - amount - fee;

  if (changeAmount < minChangeAmount) {
    throw new Error('Not enough funds to cover transaction');
  }

  return {
    utxos: targetUtxos,
    total,
    changeAmount,
  };
}