Zebra/zebra-chain/src/block/tests/vectors.rs

use std::collections::HashSet;
use std::io::{Cursor, Write};

use chrono::{DateTime, Duration, LocalResult, TimeZone, Utc};

use crate::serialization::{sha256d, ZcashDeserialize, ZcashDeserializeInto, ZcashSerialize};
use crate::transaction::LockTime;

use super::super::{serialize::MAX_BLOCK_BYTES, *};
use super::generate; // XXX this should be rewritten as strategies

#[test]
fn blockheaderhash_debug() {
    zebra_test::init();

    let preimage = b"foo bar baz";
    let mut sha_writer = sha256d::Writer::default();
    let _ = sha_writer.write_all(preimage);

    let hash = Hash(sha_writer.finish());

    assert_eq!(
        format!("{:?}", hash),
        "block::Hash(\"3166411bd5343e0b284a108f39a929fbbb62619784f8c6dafe520703b5b446bf\")"
    );
}

#[test]
fn blockheaderhash_from_blockheader() {
    zebra_test::init();

    let blockheader = generate::block_header();

    let hash = Hash::from(&blockheader);

    assert_eq!(
        format!("{:?}", hash),
        "block::Hash(\"d1d6974bbe1d4d127c889119b2fc05724c67588dc72708839727586b8c2bc939\")"
    );

    let mut bytes = Cursor::new(Vec::new());

    blockheader
        .zcash_serialize(&mut bytes)
        .expect("these bytes to serialize from a blockheader without issue");

    bytes.set_position(0);
    let other_header = bytes
        .zcash_deserialize_into()
        .expect("these bytes to deserialize into a blockheader without issue");

    assert_eq!(blockheader, other_header);
}

#[test]
fn deserialize_blockheader() {
    zebra_test::init();

    // Includes the 32-byte nonce and 3-byte equihash length field.
    const BLOCK_HEADER_LENGTH: usize = crate::work::equihash::Solution::INPUT_LENGTH
        + 32
        + 3
        + crate::work::equihash::SOLUTION_SIZE;

    for block in zebra_test::vectors::BLOCKS.iter() {
        let header_bytes = &block[..BLOCK_HEADER_LENGTH];

        let _header = header_bytes
            .zcash_deserialize_into::<Header>()
            .expect("blockheader test vector should deserialize");
    }
}

#[test]
fn deserialize_block() {
    zebra_test::init();

    // this one has a bad version field
    zebra_test::vectors::BLOCK_MAINNET_434873_BYTES
        .zcash_deserialize_into::<Block>()
        .expect("block test vector should deserialize");

    for block in zebra_test::vectors::BLOCKS.iter() {
        block
            .zcash_deserialize_into::<Block>()
            .expect("block is structurally valid");
    }
}

#[test]
fn block_test_vectors_unique() {
    zebra_test::init();

    let block_count = zebra_test::vectors::BLOCKS.len();
    let block_hashes: HashSet<_> = zebra_test::vectors::BLOCKS
        .iter()
        .map(|b| {
            b.zcash_deserialize_into::<Block>()
                .expect("block is structurally valid")
                .hash()
        })
        .collect();

    // putting the same block in two files is an easy mistake to make
    assert_eq!(
        block_count,
        block_hashes.len(),
        "block test vectors must be unique"
    );
}

#[test]
fn block_test_vectors_height_mainnet() {
    zebra_test::init();

    block_test_vectors_height(Network::Mainnet);
}

#[test]
fn block_test_vectors_height_testnet() {
    zebra_test::init();

    block_test_vectors_height(Network::Testnet);
}

fn block_test_vectors_height(network: Network) {
    let block_iter = match network {
        Network::Mainnet => zebra_test::vectors::MAINNET_BLOCKS.iter(),
        Network::Testnet => zebra_test::vectors::TESTNET_BLOCKS.iter(),
    };

    for (&height, block) in block_iter {
        let block = block
            .zcash_deserialize_into::<Block>()
            .expect("block is structurally valid");
        assert_eq!(
            block.coinbase_height().expect("block height is valid").0,
            height,
            "deserialized height must match BTreeMap key height"
        );
    }
}

#[test]
fn block_limits_multi_tx() {
    zebra_test::init();

    // Test multiple small transactions to fill a block max size

    // Create a block just below the limit
    let mut block = generate::large_multi_transaction_block();

    // Serialize the block
    let mut data = Vec::new();
    block
        .zcash_serialize(&mut data)
        .expect("block should serialize as we are not limiting generation yet");

    assert!(data.len() <= MAX_BLOCK_BYTES as usize);

    // Deserialize by now is ok as we are lower than the limit
    let block2 = Block::zcash_deserialize(&data[..])
        .expect("block should deserialize as we are just below limit");
    assert_eq!(block, block2);

    // Add 1 more transaction to the block, limit will be reached
    block = generate::oversized_multi_transaction_block();

    // Serialize will still be fine
    let mut data = Vec::new();
    block
        .zcash_serialize(&mut data)
        .expect("block should serialize as we are not limiting generation yet");

    assert!(data.len() > MAX_BLOCK_BYTES as usize);

    // Deserialize will now fail
    Block::zcash_deserialize(&data[..]).expect_err("block should not deserialize");
}

#[test]
fn block_limits_single_tx() {
    zebra_test::init();

    // Test block limit with a big single transaction

    // Create a block just below the limit
    let mut block = generate::large_single_transaction_block();

    // Serialize the block
    let mut data = Vec::new();
    block
        .zcash_serialize(&mut data)
        .expect("block should serialize as we are not limiting generation yet");

    assert!(data.len() <= MAX_BLOCK_BYTES as usize);

    // Deserialize by now is ok as we are lower than the limit
    Block::zcash_deserialize(&data[..])
        .expect("block should deserialize as we are just below limit");

    // Add 1 more input to the transaction, limit will be reached
    block = generate::oversized_single_transaction_block();

    let mut data = Vec::new();
    block
        .zcash_serialize(&mut data)
        .expect("block should serialize as we are not limiting generation yet");

    assert!(data.len() > MAX_BLOCK_BYTES as usize);

    // Will fail as block overall size is above limit
    Block::zcash_deserialize(&data[..]).expect_err("block should not deserialize");
}

/// Test wrapper for `BlockHeader.time_is_valid_at`.
///
/// Generates a block header, sets its `time` to `block_header_time`, then
/// calls `time_is_valid_at`.
fn node_time_check(
    block_header_time: DateTime<Utc>,
    now: DateTime<Utc>,
) -> Result<(), BlockTimeError> {
    let mut header = generate::block_header();
    header.time = block_header_time;
    // pass a zero height and hash - they are only used in the returned error
    header.time_is_valid_at(now, &Height(0), &Hash([0; 32]))
}

#[test]
fn time_check_now() {
    zebra_test::init();

    // These checks are deteministic, because all the times are offset
    // from the current time.
    let now = Utc::now();
    let three_hours_in_the_past = now - Duration::hours(3);
    let two_hours_in_the_future = now + Duration::hours(2);
    let two_hours_and_one_second_in_the_future = now + Duration::hours(2) + Duration::seconds(1);

    node_time_check(now, now).expect("the current time should be valid as a block header time");
    node_time_check(three_hours_in_the_past, now)
        .expect("a past time should be valid as a block header time");
    node_time_check(two_hours_in_the_future, now)
        .expect("2 hours in the future should be valid as a block header time");
    node_time_check(two_hours_and_one_second_in_the_future, now)
        .expect_err("2 hours and 1 second in the future should be invalid as a block header time");

    // Now invert the tests
    // 3 hours in the future should fail
    node_time_check(now, three_hours_in_the_past)
        .expect_err("3 hours in the future should be invalid as a block header time");
    // The past should succeed
    node_time_check(now, two_hours_in_the_future)
        .expect("2 hours in the past should be valid as a block header time");
    node_time_check(now, two_hours_and_one_second_in_the_future)
        .expect("2 hours and 1 second in the past should be valid as a block header time");
}

/// Valid unix epoch timestamps for blocks, in seconds
static BLOCK_HEADER_VALID_TIMESTAMPS: &[i64] = &[
    // These times are currently invalid DateTimes, but they could
    // become valid in future chrono versions
    i64::MIN,
    i64::MIN + 1,
    // These times are valid DateTimes
    (i32::MIN as i64) - 1,
    (i32::MIN as i64),
    (i32::MIN as i64) + 1,
    -1,
    0,
    1,
    LockTime::MIN_TIMESTAMP - 1,
    LockTime::MIN_TIMESTAMP,
    LockTime::MIN_TIMESTAMP + 1,
];

/// Invalid unix epoch timestamps for blocks, in seconds
static BLOCK_HEADER_INVALID_TIMESTAMPS: &[i64] = &[
    (i32::MAX as i64) - 1,
    (i32::MAX as i64),
    (i32::MAX as i64) + 1,
    LockTime::MAX_TIMESTAMP - 1,
    LockTime::MAX_TIMESTAMP,
    LockTime::MAX_TIMESTAMP + 1,
    // These times are currently invalid DateTimes, but they could
    // become valid in future chrono versions
    i64::MAX - 1,
    i64::MAX,
];

#[test]
fn time_check_fixed() {
    zebra_test::init();

    // These checks are non-deterministic, but the times are all in the
    // distant past or far future. So it's unlikely that the test
    // machine will have a clock that makes these tests fail.
    let now = Utc::now();

    for valid_timestamp in BLOCK_HEADER_VALID_TIMESTAMPS {
        let block_header_time = match Utc.timestamp_opt(*valid_timestamp, 0) {
            LocalResult::Single(time) => time,
            LocalResult::None => {
                // Skip the test if the timestamp is invalid
                continue;
            }
            LocalResult::Ambiguous(_, _) => {
                // Utc doesn't have ambiguous times
                unreachable!();
            }
        };
        node_time_check(block_header_time, now)
            .expect("the time should be valid as a block header time");
        // Invert the check, leading to an invalid time
        node_time_check(now, block_header_time)
            .expect_err("the inverse comparison should be invalid");
    }

    for invalid_timestamp in BLOCK_HEADER_INVALID_TIMESTAMPS {
        let block_header_time = match Utc.timestamp_opt(*invalid_timestamp, 0) {
            LocalResult::Single(time) => time,
            LocalResult::None => {
                // Skip the test if the timestamp is invalid
                continue;
            }
            LocalResult::Ambiguous(_, _) => {
                // Utc doesn't have ambiguous times
                unreachable!();
            }
        };
        node_time_check(block_header_time, now)
            .expect_err("the time should be invalid as a block header time");
        // Invert the check, leading to a valid time
        node_time_check(now, block_header_time).expect("the inverse comparison should be valid");
    }
}