Remove total_voting_power parameter from validator::Set::new

CHANGELOG.md

@@ -12,6 +12,7 @@
 - `[tendermint]` (Since v0.17.0-rc3) Bech32 encoding fix ([#690])
 - `[tendermint, light-client]` Specify the proposer in the validator set of fetched light blocks ([#705])
 - `[tendermint-proto]` (Since v0.17.0-rc3) Upgrade protobuf definitions to Tendermint Go v0.34.0 ([#737])
+- `[tendermint]` Remove `total_voting_power` parameter from `validator::Set::new` ([#739])
 
 [#425]: https://github.com/informalsystems/tendermint-rs/issues/425
 [#646]: https://github.com/informalsystems/tendermint-rs/pull/646
@@ -20,6 +21,7 @@
 [#717]: https://github.com/informalsystems/tendermint-rs/issues/717
 [#705]: https://github.com/informalsystems/tendermint-rs/issues/705
 [#737]: https://github.com/informalsystems/tendermint-rs/pull/737
+[#739]: https://github.com/informalsystems/tendermint-rs/issues/739
 
 ## v0.17.0-rc3
 

tendermint/src/error.rs

@@ -4,6 +4,7 @@ use anomaly::{BoxError, Context};
 use thiserror::Error;
 
 use crate::account;
+use crate::vote;
 
 /// Error type
 pub type Error = BoxError;
@@ -163,6 +164,15 @@ pub enum Kind {
     #[error("negative power")]
     NegativePower,
 
+    /// Mismatch between raw voting power and computed one in validator set
+    #[error("mismatch between raw voting power ({raw}) and computed one ({computed})")]
+    RawVotingPowerMismatch {
+        /// raw voting power
+        raw: vote::Power,
+        /// computed voting power
+        computed: vote::Power,
+    },
+
     /// Missing Public Key
     #[error("missing public key")]
     MissingPublicKey,

tendermint/src/validator.rs

@@ -25,16 +25,26 @@ impl TryFrom<RawValidatorSet> for Set {
     type Error = Error;
 
     fn try_from(value: RawValidatorSet) -> Result<Self, Self::Error> {
-        let unsorted_validators_result: Result<Vec<Info>, Error> = value
+        let validators = value
             .validators
             .into_iter()
             .map(TryInto::try_into)
-            .collect();
-        Ok(Self::new(
-            unsorted_validators_result?,
-            value.proposer.map(TryInto::try_into).transpose()?,
-            Some(value.total_voting_power.try_into()?),
-        ))
+            .collect::<Result<Vec<_>, _>>()?;
+
+        let proposer = value.proposer.map(TryInto::try_into).transpose()?;
+        let validator_set = Self::new(validators, proposer);
+
+        // Ensure that the raw voting power matches the computed one
+        let raw_voting_power = value.total_voting_power.try_into()?;
+        if raw_voting_power != validator_set.total_voting_power() {
+            return Err(Kind::RawVotingPowerMismatch {
+                raw: raw_voting_power,
+                computed: validator_set.total_voting_power(),
+            }
+            .into());
+        }
+
+        Ok(validator_set)
     }
 }
 
@@ -50,23 +60,16 @@ impl From<Set> for RawValidatorSet {
 
 impl Set {
     /// Constructor
-    pub fn new(
-        validators: Vec<Info>,
-        proposer: Option<Info>,
-        total_voting_power: Option<vote::Power>,
-    ) -> Set {
-        let mut validators = validators;
+    pub fn new(mut validators: Vec<Info>, proposer: Option<Info>) -> Set {
         Self::sort_validators(&mut validators);
 
         // Compute the total voting power
-        let total_voting_power = total_voting_power.unwrap_or_else(|| {
-            validators
-                .iter()
-                .map(|v| v.voting_power.value())
-                .sum::<u64>()
-                .try_into()
-                .unwrap()
-        });
+        let total_voting_power = validators
+            .iter()
+            .map(|v| v.voting_power.value())
+            .sum::<u64>()
+            .try_into()
+            .unwrap();
 
         Set {
             validators,
@@ -77,7 +80,7 @@ impl Set {
 
     /// Convenience constructor for cases where there is no proposer
     pub fn without_proposer(validators: Vec<Info>) -> Set {
-        Self::new(validators, None, None)
+        Self::new(validators, None)
     }
 
     /// Convenience constructor for cases where there is a proposer
@@ -94,7 +97,7 @@ impl Set {
 
         // Create the validator set with the given proposer.
         // This is required by IBC on-chain validation.
-        Ok(Self::new(validators, Some(proposer), None))
+        Ok(Self::new(validators, Some(proposer)))
     }
 
     /// Get Info of the underlying validators.

tendermint/src/vote/power.rs

@@ -1,14 +1,22 @@
 //! Voting power
 
+use std::convert::{TryFrom, TryInto};
+use std::fmt;
+
 use serde::{de::Error as _, Deserialize, Deserializer, Serialize, Serializer};
 
 use crate::{Error, Kind};
-use std::convert::{TryFrom, TryInto};
 
 /// Voting power
 #[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Default)]
 pub struct Power(u64);
 
+impl fmt::Display for Power {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.value())
+    }
+}
+
 impl TryFrom<i64> for Power {
     type Error = Error;