introduce IERC20Metadata to pallet-assets-precompiles

Author: seunlanlege

substrate/frame/assets/precompiles/src/lib.rs

@@ -118,6 +118,9 @@ where
 			IERC20Calls::allowance(call) => Self::allowance(asset_id, call, env),
 			IERC20Calls::approve(call) => Self::approve(asset_id, call, env),
 			IERC20Calls::transferFrom(call) => Self::transfer_from(asset_id, call, env),
+			IERC20Calls::name(_) => Self::name(asset_id, env),
+			IERC20Calls::symbol(_) => Self::symbol(asset_id, env),
+			IERC20Calls::decimals(_) => Self::decimals(asset_id, env),
 		}
 	}
 }
@@ -322,4 +325,49 @@ where
 
 		return Ok(IERC20::transferFromCall::abi_encode_returns(&true));
 	}
+
+	/// Execute the name call.
+	fn name(
+		asset_id: <Runtime as Config<Instance>>::AssetId,
+		env: &mut impl Ext<T = Runtime>,
+	) -> Result<Vec<u8>, Error> {
+		env.charge(<Runtime as Config<Instance>>::WeightInfo::get_name())?;
+
+		let metadata = pallet_assets::Pallet::<Runtime, Instance>::get_metadata(asset_id)
+			.ok_or(Error::Revert(Revert { reason: "Metadata not found".into() }))?;
+
+		let name = alloc::string::String::from_utf8(metadata.name.to_vec())
+			.map_err(|_| Error::Revert(Revert { reason: "Invalid UTF-8 in name".into() }))?;
+
+		return Ok(IERC20::nameCall::abi_encode_returns(&name));
+	}
+
+	/// Execute the symbol call.
+	fn symbol(
+		asset_id: <Runtime as Config<Instance>>::AssetId,
+		env: &mut impl Ext<T = Runtime>,
+	) -> Result<Vec<u8>, Error> {
+		env.charge(<Runtime as Config<Instance>>::WeightInfo::get_symbol())?;
+
+		let metadata = pallet_assets::Pallet::<Runtime, Instance>::get_metadata(asset_id)
+			.ok_or(Error::Revert(Revert { reason: "Metadata not found".into() }))?;
+
+		let symbol = alloc::string::String::from_utf8(metadata.symbol.to_vec())
+			.map_err(|_| Error::Revert(Revert { reason: "Invalid UTF-8 in symbol".into() }))?;
+
+		return Ok(IERC20::symbolCall::abi_encode_returns(&symbol));
+	}
+
+	/// Execute the decimals call.
+	fn decimals(
+		asset_id: <Runtime as Config<Instance>>::AssetId,
+		env: &mut impl Ext<T = Runtime>,
+	) -> Result<Vec<u8>, Error> {
+		env.charge(<Runtime as Config<Instance>>::WeightInfo::get_decimals())?;
+
+		let metadata = pallet_assets::Pallet::<Runtime, Instance>::get_metadata(asset_id)
+			.ok_or(Error::Revert(Revert { reason: "Metadata not found".into() }))?;
+
+		return Ok(IERC20::decimalsCall::abi_encode_returns(&metadata.decimals));
+	}
 }

substrate/frame/assets/src/benchmarking.rs

@@ -641,5 +641,50 @@ benchmarks_instance_pallet! {
 		assert_eq!(Reserves::<T, I>::get(id)[0], reserve);
 	}
 
+	get_name {
+		let (asset_id, caller, _) = create_default_asset::<T, I>(true);
+		T::Currency::make_free_balance_be(&caller, DepositBalanceOf::<T, I>::max_value());
+		let name_bytes = vec![0u8; T::StringLimit::get() as usize];
+		let symbol_bytes = vec![0u8; T::StringLimit::get() as usize];
+		let origin = SystemOrigin::Signed(caller).into();
+		Assets::<T, I>::set_metadata(origin, asset_id.clone(), name_bytes.clone(), symbol_bytes, 12)?;
+	}: {
+		let _ = Pallet::<T, I>::get_metadata(asset_id.clone().into());
+	} verify {
+		let metadata = Pallet::<T, I>::get_metadata(asset_id.into());
+		assert!(metadata.is_some());
+		assert_eq!(metadata.unwrap().name.to_vec(), name_bytes);
+	}
+
+	get_symbol {
+		let (asset_id, caller, _) = create_default_asset::<T, I>(true);
+		T::Currency::make_free_balance_be(&caller, DepositBalanceOf::<T, I>::max_value());
+		let name_bytes = vec![0u8; T::StringLimit::get() as usize];
+		let symbol_bytes = vec![0u8; T::StringLimit::get() as usize];
+		let origin = SystemOrigin::Signed(caller).into();
+		Assets::<T, I>::set_metadata(origin, asset_id.clone(), name_bytes, symbol_bytes.clone(), 12)?;
+	}: {
+		let _ = Pallet::<T, I>::get_metadata(asset_id.clone().into());
+	} verify {
+		let metadata = Pallet::<T, I>::get_metadata(asset_id.into());
+		assert!(metadata.is_some());
+		assert_eq!(metadata.unwrap().symbol.to_vec(), symbol_bytes);
+	}
+
+	get_decimals {
+		let (asset_id, caller, _) = create_default_asset::<T, I>(true);
+		T::Currency::make_free_balance_be(&caller, DepositBalanceOf::<T, I>::max_value());
+		let name_bytes = vec![0u8; T::StringLimit::get() as usize];
+		let symbol_bytes = vec![0u8; T::StringLimit::get() as usize];
+		let origin = SystemOrigin::Signed(caller).into();
+		Assets::<T, I>::set_metadata(origin, asset_id.clone(), name_bytes, symbol_bytes, 12)?;
+	}: {
+		let _ = Pallet::<T, I>::get_metadata(asset_id.clone().into());
+	} verify {
+		let metadata = Pallet::<T, I>::get_metadata(asset_id.into());
+		assert!(metadata.is_some());
+		assert_eq!(metadata.unwrap().decimals, 12);
+	}
+
 	impl_benchmark_test_suite!(Assets, crate::mock::new_test_ext(), crate::mock::Test)
 }

substrate/frame/assets/src/weights.rs

@@ -7,57 +7,66 @@ pragma solidity ^0.8.20;
 /// @dev Interface of the ERC-20 standard as defined in the ERC.
 ///
 interface IERC20 {
-     /// @dev Emitted when `value` tokens are moved from one account (`from`) to
-     /// another (`to`).
-     ///
-     /// Note that `value` may be zero.
+    /// @dev Emitted when `value` tokens are moved from one account (`from`) to
+    /// another (`to`).
+    ///
+    /// Note that `value` may be zero.
     event Transfer(address indexed from, address indexed to, uint256 value);
 
-     /// @dev Emitted when the allowance of a `spender` for an `owner` is set by
-     /// a call to {approve}. `value` is the new allowance.
+    /// @dev Emitted when the allowance of a `spender` for an `owner` is set by
+    /// a call to {approve}. `value` is the new allowance.
     event Approval(address indexed owner, address indexed spender, uint256 value);
 
-     /// @dev Returns the value of tokens in existence.
+    /// @dev Returns the name of the token.
+    function name() external view returns (string memory);
+
+    /// @dev Returns the symbol of the token.
+    function symbol() external view returns (string memory);
+
+    /// @dev Returns the decimals places of the token.
+    function decimals() external view returns (uint8);
+
+    /// @dev Returns the value of tokens in existence.
     function totalSupply() external view returns (uint256);
 
-     /// @dev Returns the value of tokens owned by `account`.
+    /// @dev Returns the value of tokens owned by `account`.
     function balanceOf(address account) external view returns (uint256);
 
-     /// @dev Moves a `value` amount of tokens from the caller's account to `to`.
-     ///
-     /// Returns a boolean value indicating whether the operation succeeded.
-     ///
-     /// Emits a {Transfer} event.
+    /// @dev Moves a `value` amount of tokens from the caller's account to `to`.
+    ///
+    /// Returns a boolean value indicating whether the operation succeeded.
+    ///
+    /// Emits a {Transfer} event.
     function transfer(address to, uint256 value) external returns (bool);
 
-     /// @dev Returns the remaining number of tokens that `spender` will be
-     /// allowed to spend on behalf of `owner` through {transferFrom}. This is
-     /// zero by default.
-     ///
-     /// This value changes when {approve} or {transferFrom} are called.
+    /// @dev Returns the remaining number of tokens that `spender` will be
+    /// allowed to spend on behalf of `owner` through {transferFrom}. This is
+    /// zero by default.
+    ///
+    /// This value changes when {approve} or {transferFrom} are called.
     function allowance(address owner, address spender) external view returns (uint256);
 
-     /// @dev Sets a `value` amount of tokens as the allowance of `spender` over the
-     /// caller's tokens.
-     ///
-     /// Returns a boolean value indicating whether the operation succeeded.
-     ///
-     /// IMPORTANT: Beware that changing an allowance with this method brings the risk
-     /// that someone may use both the old and the new allowance by unfortunate
-     /// transaction ordering. One possible solution to mitigate this race
-     /// condition is to first reduce the spender's allowance to 0 and set the
-     /// desired value afterwards:
-     /// https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
-     ///
-     /// Emits an {Approval} event.
+    /// @dev Sets a `value` amount of tokens as the allowance of `spender` over the
+    /// caller's tokens.
+    ///
+    /// Returns a boolean value indicating whether the operation succeeded.
+    ///
+    /// IMPORTANT: Beware that changing an allowance with this method brings the risk
+    /// that someone may use both the old and the new allowance by unfortunate
+    /// transaction ordering. One possible solution to mitigate this race
+    /// condition is to first reduce the spender's allowance to 0 and set the
+    /// desired value afterwards:
+    /// https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
+    ///
+    /// Emits an {Approval} event.
     function approve(address spender, uint256 value) external returns (bool);
 
-     /// @dev Moves a `value` amount of tokens from `from` to `to` using the
-     /// allowance mechanism. `value` is then deducted from the caller's
-     /// allowance.
-     ///
-     /// Returns a boolean value indicating whether the operation succeeded.
-     ///
-     /// Emits a {Transfer} event.
+    /// @dev Moves a `value` amount of tokens from `from` to `to` using the
+    /// allowance mechanism. `value` is then deducted from the caller's
+    /// allowance.
+    ///
+    /// Returns a boolean value indicating whether the operation succeeded.
+    ///
+    /// Emits a {Transfer} event.
     function transferFrom(address from, address to, uint256 value) external returns (bool);
 }