When building a transaction that spends UTXOs from unconfirmed parents, the wallet needs to know how much extra fee the child must pay to bring the ancestor package to a target feerate. This requires walking the unconfirmed ancestor graph, accumulating total weight and fees, and computing the deficit against the target.
Related: bitcoindevkit/bdk_wallet#48
When building a transaction that spends UTXOs from unconfirmed parents, the wallet needs to know how much extra fee the child must pay to bring the ancestor package to a target feerate. This requires walking the unconfirmed ancestor graph, accumulating total weight and fees, and computing the deficit against the target.
Related: bitcoindevkit/bdk_wallet#48