Move certain slashed funds and fees/tips to treasury (#814)

* Add `Slash` config value * Use `CurrencyOf<T>` to call `slash` * Add `Slash::on_unbalanced` calls where appropriate * Add test for `reject_market` slashes * Add test for dispute slashing * Add `Slash` parameter to runtime * Simplify treasury mock parameters * Add `DealWithFees` * Add test for `DealWithFees` * Add missing copyright notice * Fix test * Fix test formatting * Move 20% of transaction fees to the treasury * Parametrize burn & treasury percentage * Change burn parameters according to discussion * Change treasury burn to 10% for build-up period * Fix formatting * Apply suggestions from code review Co-authored-by: Chralt <chralt.developer@gmail.com> * Apply suggestions from code review Co-authored-by: Chralt <chralt.developer@gmail.com> * Add `is_zero` checks * Apply suggestions from code review Co-authored-by: Chralt <chralt.developer@gmail.com> * Fix formatting Co-authored-by: Chralt <chralt.developer@gmail.com>
zeitgeistpm · Oct 6, 2022 · d058a9e · d058a9e
1 parent cadca83
commit d058a9e
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Showing 10 changed files with 167 additions and 65 deletions.
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/primitives/src/constants/mock.rs b/primitives/src/constants/mock.rs
@@ -78,6 +78,12 @@ parameter_types! {
     pub const MaxReserves: u32 = 50;
 }
 
+// Treasury
+parameter_types! {
+    pub const MaxApprovals: u32 = 1;
+    pub const TreasuryPalletId: PalletId = PalletId(*b"zge/tsry");
+}
+
 // ORML
 parameter_types! {
     // ORML

diff --git a/runtime/battery-station/src/parameters.rs b/runtime/battery-station/src/parameters.rs
@@ -42,6 +42,8 @@ use zeitgeist_primitives::{constants::*, types::*};
 pub(crate) const AVERAGE_ON_INITIALIZE_RATIO: Perbill = Perbill::from_percent(10);
 pub(crate) const MAXIMUM_BLOCK_WEIGHT: Weight = WEIGHT_PER_SECOND / 2;
 pub(crate) const NORMAL_DISPATCH_RATIO: Perbill = Perbill::from_percent(75);
+pub(crate) const FEES_AND_TIPS_TREASURY_PERCENTAGE: u32 = 100;
+pub(crate) const FEES_AND_TIPS_BURN_PERCENTAGE: u32 = 0;
 
 parameter_types! {
     // Authorized
@@ -288,7 +290,7 @@ parameter_types! {
 
     // Treasury
     /// Percentage of spare funds (if any) that are burnt per spend period.
-    pub const Burn: Permill = Permill::from_percent(50);
+    pub const Burn: Permill = Permill::from_percent(10);
     /// The maximum number of approvals that can wait in the spending queue.
     pub const MaxApprovals: u32 = 100;
     /// Fraction of a proposal's value that should be bonded in order to place the proposal.

diff --git a/runtime/common/src/lib.rs b/runtime/common/src/lib.rs
@@ -1,4 +1,5 @@
 // Copyright 2021-2022 Zeitgeist PM LLC.
+// Copyright 2019-2020 Parity Technologies (UK) Ltd.
 //
 // This file is part of Zeitgeist.
 //
@@ -14,6 +15,25 @@
 //
 // You should have received a copy of the GNU General Public License
 // along with Zeitgeist. If not, see <https://www.gnu.org/licenses/>.
+//
+// This file incorporates work covered by the following copyright and
+// permission notice:
+//
+//     Copyright (C) 2020-2022 Acala Foundation.
+//     SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+//
+//     This program 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.
+//
+//     This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
 
 #![cfg_attr(not(feature = "std"), no_std)]
 #![recursion_limit = "256"]
@@ -25,6 +45,7 @@ pub mod weights;
 macro_rules! decl_common_types {
     {} => {
         use sp_runtime::generic;
+        use frame_support::traits::{Currency, Imbalance, OnUnbalanced};
 
         pub type Block = generic::Block<Header, UncheckedExtrinsic>;
 
@@ -161,6 +182,25 @@ macro_rules! decl_common_types {
             }
         }
 
+        pub struct DealWithFees;
+
+        type NegativeImbalance = <Balances as Currency<AccountId>>::NegativeImbalance;
+        impl OnUnbalanced<NegativeImbalance> for DealWithFees
+        {
+            fn on_unbalanceds<B>(mut fees_then_tips: impl Iterator<Item = NegativeImbalance>) {
+                if let Some(mut fees) = fees_then_tips.next() {
+                    if let Some(tips) = fees_then_tips.next() {
+                        tips.merge_into(&mut fees);
+                    }
+                    let mut split = fees.ration(
+                        FEES_AND_TIPS_TREASURY_PERCENTAGE,
+                        FEES_AND_TIPS_BURN_PERCENTAGE,
+                    );
+                    Treasury::on_unbalanced(split.0);
+                }
+            }
+        }
+
         pub mod opaque {
             //! Opaque types. These are used by the CLI to instantiate machinery that don't need to know
             //! the specifics of the runtime. They can then be made to be agnostic over specific formats
@@ -750,7 +790,8 @@ macro_rules! impl_config_traits {
         impl pallet_transaction_payment::Config for Runtime {
             type FeeMultiplierUpdate = SlowAdjustingFeeUpdate<Runtime>;
             type LengthToFee = ConstantMultiplier<Balance, TransactionByteFee>;
-            type OnChargeTransaction = pallet_transaction_payment::CurrencyAdapter<Balances, ()>;
+            type OnChargeTransaction =
+                pallet_transaction_payment::CurrencyAdapter<Balances, DealWithFees>;
             type OperationalFeeMultiplier = OperationalFeeMultiplier;
             type WeightToFee = IdentityFee<Balance>;
         }
@@ -886,6 +927,7 @@ macro_rules! impl_config_traits {
             type ResolveOrigin = EnsureRoot<AccountId>;
             type AssetManager = AssetManager;
             type SimpleDisputes = SimpleDisputes;
+            type Slash = Treasury;
             type Swaps = Swaps;
             type ValidityBond = ValidityBond;
             type WeightInfo = zrml_prediction_markets::weights::WeightInfo<Runtime>;
@@ -1684,6 +1726,29 @@ macro_rules! create_common_tests {
                     })
                 }
             }
+
+            mod deal_with_fees {
+                use crate::*;
+
+                #[test]
+                fn treasury_receives_correct_amount_of_fees_and_tips() {
+                    let mut t: sp_io::TestExternalities =
+                        frame_system::GenesisConfig::default().build_storage::<Runtime>().unwrap().into();
+                    t.execute_with(|| {
+                        let fee_balance = 3 * ExistentialDeposit::get();
+                        let fee_imbalance = Balances::issue(fee_balance);
+                        let tip_balance = 7 * ExistentialDeposit::get();
+                        let tip_imbalance = Balances::issue(tip_balance);
+                        assert_eq!(Balances::free_balance(Treasury::account_id()), 0);
+                        DealWithFees::on_unbalanceds(vec![fee_imbalance, tip_imbalance].into_iter());
+                        assert_eq!(
+                            Balances::free_balance(Treasury::account_id()),
+                            fee_balance + tip_balance,
+                        );
+                    });
+                }
+            }
         }
+
     }
 }
diff --git a/runtime/zeitgeist/src/parameters.rs b/runtime/zeitgeist/src/parameters.rs
@@ -42,6 +42,8 @@ use zeitgeist_primitives::{constants::*, types::*};
 pub(crate) const AVERAGE_ON_INITIALIZE_RATIO: Perbill = Perbill::from_percent(10);
 pub(crate) const MAXIMUM_BLOCK_WEIGHT: Weight = WEIGHT_PER_SECOND / 2;
 pub(crate) const NORMAL_DISPATCH_RATIO: Perbill = Perbill::from_percent(75);
+pub(crate) const FEES_AND_TIPS_TREASURY_PERCENTAGE: u32 = 100;
+pub(crate) const FEES_AND_TIPS_BURN_PERCENTAGE: u32 = 0;
 
 parameter_types! {
     // Authorized
@@ -288,7 +290,7 @@ parameter_types! {
 
     // Treasury
     /// Percentage of spare funds (if any) that are burnt per spend period.
-    pub const Burn: Permill = Permill::from_percent(50);
+    pub const Burn: Permill = Permill::from_percent(10);
     /// The maximum number of approvals that can wait in the spending queue.
     pub const MaxApprovals: u32 = 100;
     /// Fraction of a proposal's value that should be bonded in order to place the proposal.

diff --git a/zrml/prediction-markets/Cargo.toml b/zrml/prediction-markets/Cargo.toml
@@ -21,6 +21,7 @@ orml-tokens = { branch = "2022-06-v0.9.19", git = "https://github.com/zeitgeistp
 pallet-balances = { branch = "moonbeam-polkadot-v0.9.19", git = "https://github.com/purestake/substrate", optional = true }
 pallet-randomness-collective-flip = { branch = "moonbeam-polkadot-v0.9.19", git = "https://github.com/purestake/substrate", optional = true }
 pallet-timestamp = { branch = "moonbeam-polkadot-v0.9.19", default-features = false, git = "https://github.com/purestake/substrate", optional = true }
+pallet-treasury = { branch = "moonbeam-polkadot-v0.9.19", git = "https://github.com/purestake/substrate", optional = true }
 sp-api = { branch = "moonbeam-polkadot-v0.9.19", git = "https://github.com/purestake/substrate", optional = true }
 sp-io = { branch = "moonbeam-polkadot-v0.9.19", git = "https://github.com/purestake/substrate", optional = true }
 substrate-fixed = { optional = true, git = "https://github.com/encointer/substrate-fixed" }
@@ -40,14 +41,15 @@ mock = [
     "orml-tokens",
     "pallet-balances",
     "pallet-randomness-collective-flip",
+    "pallet-timestamp/std",
+    "pallet-treasury",
     "sp-api",
     "sp-io",
     "substrate-fixed",
     "zeitgeist-primitives/mock",
     "zrml-prediction-markets-runtime-api",
     "zrml-rikiddo",
     "zrml-swaps",
-    "pallet-timestamp/std",
 ]
 runtime-benchmarks = [
     "frame-benchmarking/runtime-benchmarks",

diff --git a/zrml/prediction-markets/src/lib.rs b/zrml/prediction-markets/src/lib.rs
@@ -39,7 +39,10 @@ mod pallet {
         ensure, log,
         pallet_prelude::{ConstU32, StorageMap, StorageValue, ValueQuery},
         storage::{with_transaction, TransactionOutcome},
-        traits::{EnsureOrigin, Get, Hooks, IsType, StorageVersion},
+        traits::{
+            Currency, EnsureOrigin, Get, Hooks, Imbalance, IsType, NamedReservableCurrency,
+            OnUnbalanced, StorageVersion,
+        },
         transactional,
         weights::Pays,
         Blake2_128Concat, BoundedVec, PalletId, Twox64Concat,
@@ -69,6 +72,10 @@ mod pallet {
     pub(crate) type BalanceOf<T> = <<T as Config>::AssetManager as MultiCurrency<
         <T as frame_system::Config>::AccountId,
     >>::Balance;
+    pub(crate) type CurrencyOf<T> =
+        <<T as Config>::MarketCommons as MarketCommonsPalletApi>::Currency;
+    pub(crate) type NegativeImbalanceOf<T> =
+        <CurrencyOf<T> as Currency<<T as frame_system::Config>::AccountId>>::NegativeImbalance;
     pub(crate) type TimeFrame = u64;
     pub(crate) type MarketIdOf<T> =
         <<T as Config>::MarketCommons as MarketCommonsPalletApi>::MarketId;
@@ -1216,6 +1223,9 @@ mod pallet {
             Origin = Self::Origin,
         >;
 
+        /// Handler for slashed funds.
+        type Slash: OnUnbalanced<NegativeImbalanceOf<Self>>;
+
         /// Swaps pallet API
         type Swaps: Swaps<Self::AccountId, Balance = BalanceOf<Self>, MarketId = MarketIdOf<Self>>;
 
@@ -1671,12 +1681,12 @@ mod pallet {
                 T::AdvisoryBondSlashPercentage::get().mul_floor(T::AdvisoryBond::get());
             let advisory_bond_unreserve_amount =
                 T::AdvisoryBond::get().saturating_sub(advisory_bond_slash_amount);
-            T::AssetManager::slash_reserved_named(
+            let (imbalance, _) = CurrencyOf::<T>::slash_reserved_named(
                 &Self::reserve_id(),
-                Asset::Ztg,
                 creator,
-                advisory_bond_slash_amount,
+                advisory_bond_slash_amount.saturated_into::<u128>().saturated_into(),
             );
+            T::Slash::on_unbalanced(imbalance);
             T::AssetManager::unreserve_named(
                 &Self::reserve_id(),
                 Asset::Ztg,
@@ -1935,10 +1945,9 @@ mod pallet {
 
                     let mut correct_reporters: Vec<T::AccountId> = Vec::new();
 
-                    let mut overall_imbalance = BalanceOf::<T>::zero();
-
                     // If the oracle reported right, return the OracleBond, otherwise slash it to
                     // pay the correct reporters.
+                    let mut overall_imbalance = NegativeImbalanceOf::<T>::zero();
                     if report.outcome == resolved_outcome {
                         T::AssetManager::unreserve_named(
                             &Self::reserve_id(),
@@ -1947,16 +1956,12 @@ mod pallet {
                             T::OracleBond::get(),
                         );
                     } else {
-                        let excess = T::AssetManager::slash_reserved_named(
+                        let (imbalance, _) = CurrencyOf::<T>::slash_reserved_named(
                             &Self::reserve_id(),
-                            Asset::Ztg,
                             &market.creator,
-                            T::OracleBond::get(),
+                            T::OracleBond::get().saturated_into::<u128>().saturated_into(),
                         );
-
-                        // negative_imbalance is the actual slash value (excess should be zero)
-                        let negative_imbalance = T::OracleBond::get().saturating_sub(excess);
-                        overall_imbalance = overall_imbalance.saturating_add(negative_imbalance);
+                        overall_imbalance.subsume(imbalance);
                     }
 
                     for (i, dispute) in disputes.iter().enumerate() {
@@ -1971,42 +1976,30 @@ mod pallet {
 
                             correct_reporters.push(dispute.by.clone());
                         } else {
-                            let excess = T::AssetManager::slash_reserved_named(
+                            let (imbalance, _) = CurrencyOf::<T>::slash_reserved_named(
                                 &Self::reserve_id(),
-                                Asset::Ztg,
                                 &dispute.by,
-                                actual_bond,
+                                actual_bond.saturated_into::<u128>().saturated_into(),
                             );
-
-                            // negative_imbalance is the actual slash value (excess should be zero)
-                            let negative_imbalance = actual_bond.saturating_sub(excess);
-                            overall_imbalance =
-                                overall_imbalance.saturating_add(negative_imbalance);
+                            overall_imbalance.subsume(imbalance);
                         }
                     }
 
                     // Fold all the imbalances into one and reward the correct reporters. The
                     // number of correct reporters might be zero if the market defaults to the
                     // report after abandoned dispute. In that case, the rewards remain slashed.
-                    if let Some(reward_per_each) =
-                        overall_imbalance.checked_div(&correct_reporters.len().saturated_into())
+                    if let Some(reward_per_each) = overall_imbalance
+                        .peek()
+                        .checked_div(&correct_reporters.len().saturated_into())
                     {
                         for correct_reporter in &correct_reporters {
-                            // *Should* always be equal to `reward_per_each`
-                            let reward = overall_imbalance.min(reward_per_each);
-                            overall_imbalance = overall_imbalance.saturating_sub(reward);
-
-                            if let Err(err) =
-                                T::AssetManager::deposit(Asset::Ztg, correct_reporter, reward)
-                            {
-                                log::warn!(
-                                    "[PredictionMarkets] Cannot deposit to the correct reporter. \
-                                     error: {:?}",
-                                    err
-                                );
-                            }
+                            let (actual_reward, leftover) =
+                                overall_imbalance.split(reward_per_each);
+                            overall_imbalance = leftover;
+                            CurrencyOf::<T>::resolve_creating(correct_reporter, actual_reward);
                         }
                     }
+                    T::Slash::on_unbalanced(overall_imbalance);
 
                     resolved_outcome
                 }

diff --git a/zrml/prediction-markets/src/migrations.rs b/zrml/prediction-markets/src/migrations.rs
@@ -15,9 +15,11 @@
 // You should have received a copy of the GNU General Public License
 // along with Zeitgeist. If not, see <https://www.gnu.org/licenses/>.
 
+#[cfg(feature = "try-runtime")]
+use crate::Disputes;
 use crate::{
-    CacheSize, Config, Disputes, MarketIdOf, MarketIdsPerDisputeBlock, MarketIdsPerReportBlock,
-    MomentOf, Pallet,
+    CacheSize, Config, MarketIdOf, MarketIdsPerDisputeBlock, MarketIdsPerReportBlock, MomentOf,
+    Pallet,
 };
 use frame_support::{
     dispatch::Weight,
@@ -36,6 +38,7 @@ use zeitgeist_primitives::types::{
     Deadlines, Market, MarketCreation, MarketDisputeMechanism, MarketPeriod, MarketStatus,
     MarketType, OutcomeReport, Report, ScoringRule,
 };
+#[cfg(feature = "try-runtime")]
 use zrml_market_commons::MarketCommonsPalletApi;
 
 const PREDICTION_MARKETS_REQUIRED_STORAGE_VERSION_FOR_MIGRATE_MARKET_IDS_STORAGE: u16 = 4;