Function history_info 

pub fn history_info<T, K, C>(
    cursor: &mut C,
    key: K,
    block_number: BlockNumber,
    key_filter: impl Fn(&K) -> bool,
    lowest_available_block_number: Option<BlockNumber>,
) -> ProviderResult<HistoryInfo>
where
    T: Table<Key = K, Value = BlockNumberList>,
    C: DbCursorRO<T>,

Generic history lookup for sharded history tables.

Seeks to the shard containing block_number, verifies the key via key_filter, and checks previous shard to detect if we’re before the first write.