1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119

//! Tendermint consensus state

pub use crate::block;
pub use std::{cmp::Ordering, fmt};
#[cfg(feature = "serde")]
use {
    crate::serializers,
    serde::{Deserialize, Serialize},
};

/// Placeholder string to show when block ID is absent. Syntax from:
/// <https://tendermint.com/docs/spec/consensus/consensus.html>
pub const NIL_PLACEHOLDER: &str = "<nil>";

/// Tendermint consensus state
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
#[derive(Clone, Debug, Default, Eq, PartialEq)]
pub struct State {
    /// Current block height
    pub height: block::Height,

    /// Current consensus round
    #[cfg_attr(
        feature = "serde",
        serde(
            serialize_with = "serializers::serialize_i64",
            deserialize_with = "serializers::parse_i64"
        )
    )]
    pub round: i64,

    /// Current consensus step
    pub step: i8,

    /// Block ID being proposed (if available)
    pub block_id: Option<block::Id>,
}

impl State {
    /// Get short prefix of the block ID for debugging purposes (ala git)
    pub fn block_id_prefix(&self) -> String {
        self.block_id
            .as_ref()
            .map(block::Id::prefix)
            .unwrap_or_else(|| NIL_PLACEHOLDER.to_owned())
    }
}

impl fmt::Display for State {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "{}/{}/{}", self.height, self.round, self.step)
    }
}

impl Ord for State {
    fn cmp(&self, other: &State) -> Ordering {
        if self.height < other.height {
            Ordering::Less
        } else if self.height == other.height {
            if self.round < other.round {
                Ordering::Less
            } else if self.round == other.round {
                self.step.cmp(&other.step)
            } else {
                Ordering::Greater
            }
        } else {
            Ordering::Greater
        }
    }
}

impl PartialOrd for State {
    fn partial_cmp(&self, other: &State) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

#[cfg(test)]
mod tests {
    use super::State;
    use crate::block;

    #[test]
    fn state_ord_test() {
        let new = State {
            height: block::Height::from(9001u64),
            round: 0,
            step: 0,
            block_id: None,
        };

        let old = State {
            height: block::Height::from(1001u64),
            round: 1,
            step: 0,
            block_id: None,
        };

        let older = State {
            height: block::Height::from(1001u64),
            round: 0,
            step: 0,
            block_id: None,
        };

        let oldest = State {
            height: block::Height::default(),
            round: 0,
            step: 0,
            block_id: None,
        };

        assert!(old < new);
        assert!(older < old);
        assert!(oldest < older);
        assert!(oldest < new);
    }
}