Function log_is_up_to_date 

pub const fn log_is_up_to_date(
    my_epoch: u32,
    my_end: i64,
    cand_epoch: u32,
    cand_offset: i64,
) -> bool

true if the candidate’s log is at least as up-to-date as ours.

KIP-595: the higher last epoch wins. On a tie, the higher or equal offset wins.