Function finalize_musig2_taproot_input

bridge/src/transactions/pre_signed_musig2.rs:149–200

(
    tx: &mut T,
    context: &dyn BaseContext,
    input_index: usize,
    sighash_type: TapSighashType,
    taproot_spend_info: TaprootSpendInfo,
)

}

pub fn finalize_musig2_taproot_input<T: PreSignedTransaction + PreSignedMusig2Transaction>(
    tx: &mut T,
    context: &dyn BaseContext,
    input_index: usize,
    sighash_type: TapSighashType,
    taproot_spend_info: TaprootSpendInfo,
) {
    // TODO: Verify we have partial signatures from all verifiers.
    // TODO: Verify each signature against the signers public key.
    // See example here: https://github.com/conduition/musig2/blob/c39bfce58098d337a3ec38b54d93def8306d9953/src/signing.rs#L358C1-L366C65

    let prev_outs = &tx.prev_outs().clone();
    let script = &tx.prev_scripts()[input_index].clone();
    let musig2_nonces: &Vec<PubNonce> =
        &tx.musig2_nonces()[&input_index].values().cloned().collect();
    let musig2_signatures: Vec<MaybeScalar> = tx.musig2_signatures()[&input_index]
        .values()
        .map(|&partial_signature| PartialSignature::from(partial_signature))
        .collect();
    let tx_mut = tx.tx_mut();

    // Aggregate signature
    let signature = generate_taproot_aggregated_signature(
        context,
        tx_mut,
        &generate_aggregated_nonce(musig2_nonces),
        input_index,
        prev_outs,
        script,
        sighash_type,
        musig2_signatures, // TODO: Is there a more elegant way of doing this?
    )
    .unwrap(); // TODO: Add error handling.

    let final_signature = bitcoin::taproot::Signature {
        signature: signature.into(),
        sighash_type,
    };

    // Push signature to witness
    tx_mut.input[input_index]
        .witness
        .push(final_signature.serialize());

    // Push script + control block
    push_taproot_leaf_script_and_control_block_to_witness(
        tx_mut,
        input_index,
        &taproot_spend_info,
        script,
    );
}