Fixed GA test (#147)

Author: KarishmaBothara

prml/generic-asset/src/imbalances.rs

@@ -36,6 +36,7 @@ use sp_std::{mem, result};
 /// denoting that funds have been created without any equal and opposite
 /// accounting.
 #[must_use]
+#[derive(Debug)]
 pub struct PositiveImbalance<T: Trait> {
 	amount: T::Balance,
 	asset_id: T::AssetId,
@@ -52,6 +53,7 @@ impl<T: Trait> PositiveImbalance<T> {
 /// denoting that funds have been destroyed without any equal and opposite
 /// accounting.
 #[must_use]
+#[derive(Debug)]
 pub struct NegativeImbalance<T: Trait> {
 	amount: T::Balance,
 	asset_id: T::AssetId,
@@ -77,7 +79,7 @@ impl<T: Trait> Imbalance<T::Balance> for PositiveImbalance<T> {
 		Self::new(Zero::zero(), Zero::zero())
 	}
 	fn drop_zero(self) -> result::Result<(), Self> {
-		if self.amount.is_zero() {
+		if self.amount.is_zero() || self.asset_id.is_zero() {
 			Ok(())
 		} else {
 			Err(self)
@@ -130,7 +132,7 @@ impl<T: Trait> Imbalance<T::Balance> for NegativeImbalance<T> {
 		Self::new(Zero::zero(), Zero::zero())
 	}
 	fn drop_zero(self) -> result::Result<(), Self> {
-		if self.amount.is_zero() {
+		if self.amount.is_zero() || self.asset_id.is_zero() {
 			Ok(())
 		} else {
 			Err(self)
@@ -185,41 +187,78 @@ impl<T: Trait> Drop for NegativeImbalance<T> {
 }
 
 /// The result of an offset operation
+#[derive(Debug)]
 pub enum OffsetResult<T: Trait, I: Imbalance<T::Balance>> {
 	Imbalance(I),
 	Opposite(I::Opposite),
 }
 
+#[derive(Debug, PartialEq, Eq)]
+pub enum Error {
+	/// The operation cannot occur on imbalances with different asset IDs
+	DifferentAssetIds,
+	/// The operation cannot occur when asset id is 0 and amount is not 0
+	ZeroIdWithNonZeroAmount,
+}
+
 /// Provides a safe API around imbalances with asset ID awareness
 pub trait CheckedImbalance<T: Trait>: Imbalance<T::Balance> {
 	/// Get the imbalance asset ID
 	fn asset_id(&self) -> T::AssetId;
 	/// Get the imbalance amount
 	fn amount(&self) -> T::Balance;
+	/// Set the imbalance asset ID
+	fn set_asset_id(&mut self, new_asset_id: T::AssetId);
 	/// Offset with asset ID safety checks
-	fn checked_offset(self, other: Self::Opposite) -> result::Result<OffsetResult<T, Self>, ()>
+	fn checked_offset(self, other: Self::Opposite) -> result::Result<OffsetResult<T, Self>, Error>
 	where
 		Self::Opposite: CheckedImbalance<T>,
 	{
+		if other.asset_id().is_zero() {
+			return Ok(OffsetResult::Imbalance(self))
+		}
+		if self.asset_id().is_zero() && !self.amount().is_zero() {
+			return Err(Error::ZeroIdWithNonZeroAmount);
+		}
 		if self.asset_id() != other.asset_id() {
-			return Err(());
+			return Err(Error::DifferentAssetIds);
 		}
 		match self.offset(other) {
 			Ok(i) => Ok(OffsetResult::Imbalance(i)),
 			Err(i) => Ok(OffsetResult::Opposite(i)),
 		}
 	}
 	/// Subsume with asset ID safety checks
-	fn checked_subsume(&mut self, other: Self) -> result::Result<(), ()> {
+	fn checked_subsume(&mut self, other: Self) -> result::Result<(), Error> {
+		if other.asset_id().is_zero() {
+			// noop, rhs is 0
+			return Ok(());
+		}
+		if self.asset_id().is_zero() && !self.amount().is_zero() {
+			return Err(Error::ZeroIdWithNonZeroAmount);
+		}
+		if self.asset_id().is_zero() {
+			self.set_asset_id(other.asset_id());
+		}
 		if self.asset_id() != other.asset_id() {
-			return Err(());
+			return Err(Error::DifferentAssetIds);
 		}
 		Ok(self.subsume(other))
 	}
 	/// Merge with asset ID safety checks
-	fn checked_merge(self, other: Self) -> result::Result<Self, ()> {
+	fn checked_merge(mut self, other: Self) -> result::Result<Self, Error> {
+		if other.asset_id().is_zero() {
+			// noop, rhs is 0
+			return Ok(self);
+		}
+		if self.asset_id().is_zero() && !self.amount().is_zero() {
+			return Err(Error::ZeroIdWithNonZeroAmount);
+		}
+		if self.asset_id().is_zero() {
+			self.set_asset_id(other.asset_id());
+		}
 		if self.asset_id() != other.asset_id() {
-			return Err(());
+			return Err(Error::DifferentAssetIds);
 		}
 		Ok(self.merge(other))
 	}
@@ -232,6 +271,10 @@ impl<T: Trait> CheckedImbalance<T> for PositiveImbalance<T> {
 	fn amount(&self) -> T::Balance {
 		self.amount
 	}
+	/// Set the imbalance asset ID
+	fn set_asset_id(&mut self, new_asset_id: T::AssetId) {
+		self.asset_id = new_asset_id;
+	}
 }
 
 impl<T: Trait> CheckedImbalance<T> for NegativeImbalance<T> {
@@ -241,4 +284,8 @@ impl<T: Trait> CheckedImbalance<T> for NegativeImbalance<T> {
 	fn amount(&self) -> T::Balance {
 		self.amount
 	}
+	/// Set the imbalance asset ID
+	fn set_asset_id(&mut self, new_asset_id: T::AssetId) {
+		self.asset_id = new_asset_id;
+	}
 }

prml/generic-asset/src/lib.rs

@@ -163,12 +163,12 @@ use frame_support::{
 	decl_error, decl_event, decl_module, decl_storage, ensure,
 	traits::{
 		BalanceStatus, Currency, ExistenceRequirement, Imbalance, LockIdentifier, LockableCurrency, ReservableCurrency,
-		SignedImbalance, TryDrop, WithdrawReason, WithdrawReasons,
+		SignedImbalance, WithdrawReason, WithdrawReasons,
 	},
 	weights::Weight,
 	Parameter, StorageMap,
 };
-use frame_system::{self as system, ensure_root, ensure_signed};
+use frame_system::{ensure_root, ensure_signed};
 use sp_std::prelude::*;
 use sp_std::{cmp, fmt::Debug, result};
 
@@ -699,36 +699,20 @@ impl<T: Trait> Module<T> {
 	/// - the `slashed` id equal to `beneficiary` and the `status` is `Reserved`.
 	pub fn repatriate_reserved(
 		asset_id: T::AssetId,
-		slashed: &T::AccountId,
+		who: &T::AccountId,
 		beneficiary: &T::AccountId,
-		value: T::Balance,
-		status: BalanceStatus,
+		amount: T::Balance,
 	) -> Result<T::Balance, DispatchError> {
-		Ok(Zero::zero())
-		// TODO:
-		// if value.is_zero() { return Ok(Zero::zero()) }
-
-		// if slashed == beneficiary {
-		// 	return match status {
-		// 		BalanceStatus::Free => Ok(Self::unreserve(asset_id, slashed, value)),
-		// 		BalanceStatus::Reserved => Ok(value.saturating_sub(Self::reserved_balance(asset_id, slashed))),
-		// 	};
-		// }
-
-		// let actual = Self::try_mutate_account(beneficiary, |to_account, is_new|-> Result<T::Balance, DispatchError> {
-		// 	ensure!(!is_new, Error::<T, I>::DeadAccount);
-		// 	Self::try_mutate_account(slashed, |from_account, _| -> Result<T::Balance, DispatchError> {
-		// 		let actual = cmp::min(from_account.reserved, value);
-		// 		match status {
-		// 			BalanceStatus::Free => to_account.free = to_account.free.checked_add(&actual).ok_or(Error::<T, I>::Overflow)?,
-		// 			BalanceStatus::Reserved => to_account.reserved = to_account.reserved.checked_add(&actual).ok_or(Error::<T, I>::Overflow)?,
-		// 		}
-		// 		from_account.reserved -= actual;
-		// 		Ok(actual)
-		// 	})
-		// })?;
-
-		// Ok(value - actual)
+		let b = Self::reserved_balance(asset_id, who);
+		let slash = sp_std::cmp::min(b, amount);
+
+		let original_free_balance = Self::free_balance(asset_id, beneficiary);
+		let new_free_balance = original_free_balance + slash;
+		Self::set_free_balance(asset_id, beneficiary, new_free_balance);
+
+		let new_reserve_balance = b - slash;
+		Self::set_reserved_balance(asset_id, who, new_reserve_balance);
+		Ok(amount - slash)
 	}
 
 	/// Check permission to perform burn, mint or update.
@@ -1018,9 +1002,9 @@ where
 		slashed: &T::AccountId,
 		beneficiary: &T::AccountId,
 		value: Self::Balance,
-		status: BalanceStatus,
+		_status: BalanceStatus,
 	) -> result::Result<Self::Balance, DispatchError> {
-		<Module<T>>::repatriate_reserved(U::asset_id(), slashed, beneficiary, value, status)
+		<Module<T>>::repatriate_reserved(U::asset_id(), slashed, beneficiary, value)
 	}
 }
 

prml/generic-asset/src/mock.rs

@@ -71,30 +71,38 @@ parameter_types! {
 	pub const AvailableBlockRatio: Perbill = Perbill::one();
 }
 impl frame_system::Trait for Test {
+	type BaseCallFilter = ();
 	type Origin = Origin;
 	type Index = u64;
 	type BlockNumber = u64;
 	type Call = ();
 	type Hash = H256;
 	type Hashing = BlakeTwo256;
 	type AccountId = u64;
-	type Lookup = IdentityLookup<u64>;
+	type Lookup = IdentityLookup<Self::AccountId>;
 	type Header = Header;
+	type BlockHashCount = BlockHashCount;
 	type Event = TestEvent;
+	type DbWeight = ();
+	type BlockExecutionWeight = ();
+	type ExtrinsicBaseWeight = ();
+	type MaximumExtrinsicWeight = MaximumBlockWeight;
 	type MaximumBlockWeight = MaximumBlockWeight;
 	type MaximumBlockLength = MaximumBlockLength;
 	type AvailableBlockRatio = AvailableBlockRatio;
-	type BlockHashCount = BlockHashCount;
 	type Version = ();
-	type ModuleToIndex = ();
-	type Doughnut = ();
-	type DelegatedDispatchVerifier = ();
+	type PalletInfo = ();
+	type AccountData = ();
+	type OnNewAccount = ();
+	type OnKilledAccount = ();
+	type SystemWeightInfo = ();
 }
 
 impl Trait for Test {
 	type Balance = u64;
 	type AssetId = u32;
 	type Event = TestEvent;
+	type WeightInfo = ();
 }
 
 mod generic_asset {
@@ -104,7 +112,7 @@ mod generic_asset {
 use frame_system as system;
 impl_outer_event! {
 	pub enum TestEvent for Test {
-		system,
+		system<T>,
 		generic_asset<T>,
 	}
 }