bdk/crates/electrum/tests/test_electrum.rs

use bdk_chain::{
    bitcoin::{hashes::Hash, Address, Amount, ScriptBuf, Txid, WScriptHash},
    local_chain::LocalChain,
    spk_client::{FullScanRequest, SyncRequest},
    Balance, ConfirmationBlockTime, IndexedTxGraph, SpkTxOutIndex,
};
use bdk_electrum::BdkElectrumClient;
use bdk_testenv::{anyhow, bitcoincore_rpc::RpcApi, TestEnv};
use std::collections::{BTreeSet, HashSet};
use std::str::FromStr;

fn get_balance(
    recv_chain: &LocalChain,
    recv_graph: &IndexedTxGraph<ConfirmationBlockTime, SpkTxOutIndex<()>>,
) -> anyhow::Result<Balance> {
    let chain_tip = recv_chain.tip().block_id();
    let outpoints = recv_graph.index.outpoints().clone();
    let balance = recv_graph
        .graph()
        .balance(recv_chain, chain_tip, outpoints, |_, _| true);
    Ok(balance)
}

#[test]
pub fn test_update_tx_graph_without_keychain() -> anyhow::Result<()> {
    let env = TestEnv::new()?;
    let electrum_client = electrum_client::Client::new(env.electrsd.electrum_url.as_str())?;
    let client = BdkElectrumClient::new(electrum_client);

    let receive_address0 =
        Address::from_str("bcrt1qc6fweuf4xjvz4x3gx3t9e0fh4hvqyu2qw4wvxm")?.assume_checked();
    let receive_address1 =
        Address::from_str("bcrt1qfjg5lv3dvc9az8patec8fjddrs4aqtauadnagr")?.assume_checked();

    let misc_spks = [
        receive_address0.script_pubkey(),
        receive_address1.script_pubkey(),
    ];

    let _block_hashes = env.mine_blocks(101, None)?;
    let txid1 = env.bitcoind.client.send_to_address(
        &receive_address1,
        Amount::from_sat(10000),
        None,
        None,
        None,
        None,
        Some(1),
        None,
    )?;
    let txid2 = env.bitcoind.client.send_to_address(
        &receive_address0,
        Amount::from_sat(20000),
        None,
        None,
        None,
        None,
        Some(1),
        None,
    )?;
    env.mine_blocks(1, None)?;
    env.wait_until_electrum_sees_block()?;

    // use a full checkpoint linked list (since this is not what we are testing)
    let cp_tip = env.make_checkpoint_tip();

    let sync_update = {
        let request = SyncRequest::from_chain_tip(cp_tip.clone()).set_spks(misc_spks);
        client.sync(request, 1, true)?
    };

    assert!(
        {
            let update_cps = sync_update
                .chain_update
                .iter()
                .map(|cp| cp.block_id())
                .collect::<BTreeSet<_>>();
            let superset_cps = cp_tip
                .iter()
                .map(|cp| cp.block_id())
                .collect::<BTreeSet<_>>();
            superset_cps.is_superset(&update_cps)
        },
        "update should not alter original checkpoint tip since we already started with all checkpoints",
    );

    let graph_update = sync_update.graph_update;
    // Check to see if we have the floating txouts available from our two created transactions'
    // previous outputs in order to calculate transaction fees.
    for tx in graph_update.full_txs() {
        // Retrieve the calculated fee from `TxGraph`, which will panic if we do not have the
        // floating txouts available from the transactions' previous outputs.
        let fee = graph_update.calculate_fee(&tx.tx).expect("Fee must exist");

        // Retrieve the fee in the transaction data from `bitcoind`.
        let tx_fee = env
            .bitcoind
            .client
            .get_transaction(&tx.txid, None)
            .expect("Tx must exist")
            .fee
            .expect("Fee must exist")
            .abs()
            .to_unsigned()
            .expect("valid `Amount`");

        // Check that the calculated fee matches the fee from the transaction data.
        assert_eq!(fee, tx_fee);
    }

    let mut graph_update_txids: Vec<Txid> = graph_update.full_txs().map(|tx| tx.txid).collect();
    graph_update_txids.sort();
    let mut expected_txids = vec![txid1, txid2];
    expected_txids.sort();
    assert_eq!(graph_update_txids, expected_txids);

    Ok(())
}

/// Test the bounds of the address scan depending on the `stop_gap`.
#[test]
pub fn test_update_tx_graph_stop_gap() -> anyhow::Result<()> {
    let env = TestEnv::new()?;
    let electrum_client = electrum_client::Client::new(env.electrsd.electrum_url.as_str())?;
    let client = BdkElectrumClient::new(electrum_client);
    let _block_hashes = env.mine_blocks(101, None)?;

    // Now let's test the gap limit. First of all get a chain of 10 addresses.
    let addresses = [
        "bcrt1qj9f7r8r3p2y0sqf4r3r62qysmkuh0fzep473d2ar7rcz64wqvhssjgf0z4",
        "bcrt1qmm5t0ch7vh2hryx9ctq3mswexcugqe4atkpkl2tetm8merqkthas3w7q30",
        "bcrt1qut9p7ej7l7lhyvekj28xknn8gnugtym4d5qvnp5shrsr4nksmfqsmyn87g",
        "bcrt1qqz0xtn3m235p2k96f5wa2dqukg6shxn9n3txe8arlrhjh5p744hsd957ww",
        "bcrt1q9c0t62a8l6wfytmf2t9lfj35avadk3mm8g4p3l84tp6rl66m48sqrme7wu",
        "bcrt1qkmh8yrk2v47cklt8dytk8f3ammcwa4q7dzattedzfhqzvfwwgyzsg59zrh",
        "bcrt1qvgrsrzy07gjkkfr5luplt0azxtfwmwq5t62gum5jr7zwcvep2acs8hhnp2",
        "bcrt1qw57edarcg50ansq8mk3guyrk78rk0fwvrds5xvqeupteu848zayq549av8",
        "bcrt1qvtve5ekf6e5kzs68knvnt2phfw6a0yjqrlgat392m6zt9jsvyxhqfx67ef",
        "bcrt1qw03ddumfs9z0kcu76ln7jrjfdwam20qtffmkcral3qtza90sp9kqm787uk",
    ];
    let addresses: Vec<_> = addresses
        .into_iter()
        .map(|s| Address::from_str(s).unwrap().assume_checked())
        .collect();
    let spks: Vec<_> = addresses
        .iter()
        .enumerate()
        .map(|(i, addr)| (i as u32, addr.script_pubkey()))
        .collect();

    // Then receive coins on the 4th address.
    let txid_4th_addr = env.bitcoind.client.send_to_address(
        &addresses[3],
        Amount::from_sat(10000),
        None,
        None,
        None,
        None,
        Some(1),
        None,
    )?;
    env.mine_blocks(1, None)?;
    env.wait_until_electrum_sees_block()?;

    // use a full checkpoint linked list (since this is not what we are testing)
    let cp_tip = env.make_checkpoint_tip();

    // A scan with a stop_gap of 3 won't find the transaction, but a scan with a gap limit of 4
    // will.
    let full_scan_update = {
        let request =
            FullScanRequest::from_chain_tip(cp_tip.clone()).set_spks_for_keychain(0, spks.clone());
        client.full_scan(request, 3, 1, false)?
    };
    assert!(full_scan_update.graph_update.full_txs().next().is_none());
    assert!(full_scan_update.last_active_indices.is_empty());
    let full_scan_update = {
        let request =
            FullScanRequest::from_chain_tip(cp_tip.clone()).set_spks_for_keychain(0, spks.clone());
        client.full_scan(request, 4, 1, false)?
    };
    assert_eq!(
        full_scan_update
            .graph_update
            .full_txs()
            .next()
            .unwrap()
            .txid,
        txid_4th_addr
    );
    assert_eq!(full_scan_update.last_active_indices[&0], 3);

    // Now receive a coin on the last address.
    let txid_last_addr = env.bitcoind.client.send_to_address(
        &addresses[addresses.len() - 1],
        Amount::from_sat(10000),
        None,
        None,
        None,
        None,
        Some(1),
        None,
    )?;
    env.mine_blocks(1, None)?;
    env.wait_until_electrum_sees_block()?;

    // A scan with gap limit 5 won't find the second transaction, but a scan with gap limit 6 will.
    // The last active indice won't be updated in the first case but will in the second one.
    let full_scan_update = {
        let request =
            FullScanRequest::from_chain_tip(cp_tip.clone()).set_spks_for_keychain(0, spks.clone());
        client.full_scan(request, 5, 1, false)?
    };
    let txs: HashSet<_> = full_scan_update
        .graph_update
        .full_txs()
        .map(|tx| tx.txid)
        .collect();
    assert_eq!(txs.len(), 1);
    assert!(txs.contains(&txid_4th_addr));
    assert_eq!(full_scan_update.last_active_indices[&0], 3);
    let full_scan_update = {
        let request =
            FullScanRequest::from_chain_tip(cp_tip.clone()).set_spks_for_keychain(0, spks.clone());
        client.full_scan(request, 6, 1, false)?
    };
    let txs: HashSet<_> = full_scan_update
        .graph_update
        .full_txs()
        .map(|tx| tx.txid)
        .collect();
    assert_eq!(txs.len(), 2);
    assert!(txs.contains(&txid_4th_addr) && txs.contains(&txid_last_addr));
    assert_eq!(full_scan_update.last_active_indices[&0], 9);

    Ok(())
}

/// Ensure that [`ElectrumExt`] can sync properly.
///
/// 1. Mine 101 blocks.
/// 2. Send a tx.
/// 3. Mine extra block to confirm sent tx.
/// 4. Check [`Balance`] to ensure tx is confirmed.
#[test]
fn scan_detects_confirmed_tx() -> anyhow::Result<()> {
    const SEND_AMOUNT: Amount = Amount::from_sat(10_000);

    let env = TestEnv::new()?;
    let electrum_client = electrum_client::Client::new(env.electrsd.electrum_url.as_str())?;
    let client = BdkElectrumClient::new(electrum_client);

    // Setup addresses.
    let addr_to_mine = env
        .bitcoind
        .client
        .get_new_address(None, None)?
        .assume_checked();
    let spk_to_track = ScriptBuf::new_p2wsh(&WScriptHash::all_zeros());
    let addr_to_track = Address::from_script(&spk_to_track, bdk_chain::bitcoin::Network::Regtest)?;

    // Setup receiver.
    let (mut recv_chain, _) = LocalChain::from_genesis_hash(env.bitcoind.client.get_block_hash(0)?);
    let mut recv_graph = IndexedTxGraph::<ConfirmationBlockTime, _>::new({
        let mut recv_index = SpkTxOutIndex::default();
        recv_index.insert_spk((), spk_to_track.clone());
        recv_index
    });

    // Mine some blocks.
    env.mine_blocks(101, Some(addr_to_mine))?;

    // Create transaction that is tracked by our receiver.
    env.send(&addr_to_track, SEND_AMOUNT)?;

    // Mine a block to confirm sent tx.
    env.mine_blocks(1, None)?;

    // Sync up to tip.
    env.wait_until_electrum_sees_block()?;
    let update = client.sync(
        SyncRequest::from_chain_tip(recv_chain.tip()).chain_spks(core::iter::once(spk_to_track)),
        5,
        true,
    )?;

    let _ = recv_chain
        .apply_update(update.chain_update)
        .map_err(|err| anyhow::anyhow!("LocalChain update error: {:?}", err))?;
    let _ = recv_graph.apply_update(update.graph_update);

    // Check to see if tx is confirmed.
    assert_eq!(
        get_balance(&recv_chain, &recv_graph)?,
        Balance {
            confirmed: SEND_AMOUNT,
            ..Balance::default()
        },
    );

    for tx in recv_graph.graph().full_txs() {
        // Retrieve the calculated fee from `TxGraph`, which will panic if we do not have the
        // floating txouts available from the transaction's previous outputs.
        let fee = recv_graph
            .graph()
            .calculate_fee(&tx.tx)
            .expect("fee must exist");

        // Retrieve the fee in the transaction data from `bitcoind`.
        let tx_fee = env
            .bitcoind
            .client
            .get_transaction(&tx.txid, None)
            .expect("Tx must exist")
            .fee
            .expect("Fee must exist")
            .abs()
            .to_unsigned()
            .expect("valid `Amount`");

        // Check that the calculated fee matches the fee from the transaction data.
        assert_eq!(fee, tx_fee);
    }

    Ok(())
}

/// Ensure that confirmed txs that are reorged become unconfirmed.
///
/// 1. Mine 101 blocks.
/// 2. Mine 8 blocks with a confirmed tx in each.
/// 3. Perform 8 separate reorgs on each block with a confirmed tx.
/// 4. Check [`Balance`] after each reorg to ensure unconfirmed amount is correct.
#[test]
fn tx_can_become_unconfirmed_after_reorg() -> anyhow::Result<()> {
    const REORG_COUNT: usize = 8;
    const SEND_AMOUNT: Amount = Amount::from_sat(10_000);

    let env = TestEnv::new()?;
    let electrum_client = electrum_client::Client::new(env.electrsd.electrum_url.as_str())?;
    let client = BdkElectrumClient::new(electrum_client);

    // Setup addresses.
    let addr_to_mine = env
        .bitcoind
        .client
        .get_new_address(None, None)?
        .assume_checked();
    let spk_to_track = ScriptBuf::new_p2wsh(&WScriptHash::all_zeros());
    let addr_to_track = Address::from_script(&spk_to_track, bdk_chain::bitcoin::Network::Regtest)?;

    // Setup receiver.
    let (mut recv_chain, _) = LocalChain::from_genesis_hash(env.bitcoind.client.get_block_hash(0)?);
    let mut recv_graph = IndexedTxGraph::<ConfirmationBlockTime, _>::new({
        let mut recv_index = SpkTxOutIndex::default();
        recv_index.insert_spk((), spk_to_track.clone());
        recv_index
    });

    // Mine some blocks.
    env.mine_blocks(101, Some(addr_to_mine))?;

    // Create transactions that are tracked by our receiver.
    let mut txids = vec![];
    let mut hashes = vec![];
    for _ in 0..REORG_COUNT {
        txids.push(env.send(&addr_to_track, SEND_AMOUNT)?);
        hashes.extend(env.mine_blocks(1, None)?);
    }

    // Sync up to tip.
    env.wait_until_electrum_sees_block()?;
    let update = client.sync(
        SyncRequest::from_chain_tip(recv_chain.tip()).chain_spks([spk_to_track.clone()]),
        5,
        false,
    )?;

    let _ = recv_chain
        .apply_update(update.chain_update)
        .map_err(|err| anyhow::anyhow!("LocalChain update error: {:?}", err))?;
    let _ = recv_graph.apply_update(update.graph_update.clone());

    // Retain a snapshot of all anchors before reorg process.
    let initial_anchors = update.graph_update.all_anchors();
    let anchors: Vec<_> = initial_anchors.iter().cloned().collect();
    assert_eq!(anchors.len(), REORG_COUNT);
    for i in 0..REORG_COUNT {
        let (anchor, txid) = anchors[i];
        assert_eq!(anchor.block_id.hash, hashes[i]);
        assert_eq!(txid, txids[i]);
    }

    // Check if initial balance is correct.
    assert_eq!(
        get_balance(&recv_chain, &recv_graph)?,
        Balance {
            confirmed: SEND_AMOUNT * REORG_COUNT as u64,
            ..Balance::default()
        },
        "initial balance must be correct",
    );

    // Perform reorgs with different depths.
    for depth in 1..=REORG_COUNT {
        env.reorg_empty_blocks(depth)?;

        env.wait_until_electrum_sees_block()?;
        let update = client.sync(
            SyncRequest::from_chain_tip(recv_chain.tip()).chain_spks([spk_to_track.clone()]),
            5,
            false,
        )?;

        let _ = recv_chain
            .apply_update(update.chain_update)
            .map_err(|err| anyhow::anyhow!("LocalChain update error: {:?}", err))?;

        // Check that no new anchors are added during current reorg.
        assert!(initial_anchors.is_superset(update.graph_update.all_anchors()));
        let _ = recv_graph.apply_update(update.graph_update);

        assert_eq!(
            get_balance(&recv_chain, &recv_graph)?,
            Balance {
                confirmed: SEND_AMOUNT * (REORG_COUNT - depth) as u64,
                ..Balance::default()
            },
            "reorg_count: {}",
            depth,
        );
    }

    Ok(())
}