Files
pezkuwi-subxt/substrate/primitives/phragmen/src/helpers.rs
T
Stanislav Tkach d870eb23e1 Remove sp-runtime dependency from sp-phragmen (#5786)
* Remove sp-runtime dependency from sp-phragmen

* Use regular derive(Debug) instead of RuntimeDebug
2020-04-28 17:21:10 +02:00

99 lines
2.7 KiB
Rust

// Copyright 2020 Parity Technologies (UK) Ltd.
// This file is part of Substrate.
// Substrate is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Substrate is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Substrate. If not, see <http://www.gnu.org/licenses/>.
//! Helper methods for phragmen.
use crate::{Assignment, ExtendedBalance, VoteWeight, IdentifierT, StakedAssignment, WithApprovalOf};
use sp_arithmetic::PerThing;
use sp_std::prelude::*;
/// Converts a vector of ratio assignments into ones with absolute budget value.
pub fn assignment_ratio_to_staked<A: IdentifierT, T: PerThing, FS>(
ratio: Vec<Assignment<A, T>>,
stake_of: FS,
) -> Vec<StakedAssignment<A>>
where
for<'r> FS: Fn(&'r A) -> VoteWeight,
T: sp_std::ops::Mul<ExtendedBalance, Output = ExtendedBalance>,
ExtendedBalance: From<<T as PerThing>::Inner>,
{
ratio
.into_iter()
.map(|a| {
let stake = stake_of(&a.who);
a.into_staked(stake.into(), true)
})
.collect()
}
/// Converts a vector of staked assignments into ones with ratio values.
pub fn assignment_staked_to_ratio<A: IdentifierT, T: PerThing>(
staked: Vec<StakedAssignment<A>>,
) -> Vec<Assignment<A, T>>
where
ExtendedBalance: From<<T as PerThing>::Inner>,
{
staked.into_iter().map(|a| a.into_assignment(true)).collect()
}
/// consumes a vector of winners with backing stake to just winners.
pub fn to_without_backing<A: IdentifierT>(winners: Vec<WithApprovalOf<A>>) -> Vec<A> {
winners.into_iter().map(|(who, _)| who).collect::<Vec<A>>()
}
#[cfg(test)]
mod tests {
use super::*;
use sp_arithmetic::Perbill;
#[test]
fn into_staked_works() {
let assignments = vec![
Assignment {
who: 1u32,
distribution: vec![
(10u32, Perbill::from_fraction(0.5)),
(20, Perbill::from_fraction(0.5)),
],
},
Assignment {
who: 2u32,
distribution: vec![
(10, Perbill::from_fraction(0.33)),
(20, Perbill::from_fraction(0.67)),
],
},
];
let stake_of = |_: &u32| -> VoteWeight { 100 };
let staked = assignment_ratio_to_staked(assignments, stake_of);
assert_eq!(
staked,
vec![
StakedAssignment {
who: 1u32,
distribution: vec![(10u32, 50), (20, 50),]
},
StakedAssignment {
who: 2u32,
distribution: vec![(10u32, 33), (20, 67),]
}
]
);
}
}