From 902fcbf4551db7999022d441965fb1c8ef48215f Mon Sep 17 00:00:00 2001
From: Aleksandr Krupenkin <mail@akru.me>
Date: Fri, 21 Oct 2022 17:35:22 +0900
Subject: [PATCH] Remove chain-extension-trait package (#109)

* Remove chain-extension-trait package

* Dapps Staking CE optimizations

* Dapps Staking CE optimizations

* Rename dapps-staking CE in general way

* Derive Default for chain extension structs

* Implement Default trait for CEs

* Fix typo
---
 Cargo.toml                                    |  1 -
 chain-extensions/dapps-staking/Cargo.toml     |  7 +-
 chain-extensions/dapps-staking/src/lib.rs     | 91 +++++++------------
 chain-extensions/rmrk/Cargo.toml              |  2 -
 chain-extensions/rmrk/src/lib.rs              | 31 ++++---
 chain-extensions/trait/Cargo.toml             | 20 ----
 chain-extensions/trait/src/lib.rs             | 21 -----
 .../types/dapps-staking/Cargo.toml            |  2 +-
 .../types/dapps-staking/src/lib.rs            | 10 --
 chain-extensions/types/rmrk/src/lib.rs        |  4 +-
 chain-extensions/xvm/Cargo.toml               |  3 +-
 chain-extensions/xvm/src/lib.rs               | 26 +++---
 12 files changed, 74 insertions(+), 144 deletions(-)
 delete mode 100644 chain-extensions/trait/Cargo.toml
 delete mode 100644 chain-extensions/trait/src/lib.rs

diff --git a/Cargo.toml b/Cargo.toml
index ddb529f6..1cb716d7 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,7 +3,6 @@ members = [
 	"chain-extensions/dapps-staking",
 	"chain-extensions/rmrk",
 	"chain-extensions/xvm",
-	"chain-extensions/trait",
 	"chain-extensions/types/*",
 	"frame/block-reward",
 	"frame/collator-selection",
diff --git a/chain-extensions/dapps-staking/Cargo.toml b/chain-extensions/dapps-staking/Cargo.toml
index 1263c608..4a6bd739 100644
--- a/chain-extensions/dapps-staking/Cargo.toml
+++ b/chain-extensions/dapps-staking/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
-name = "dapps-staking-chain-extension"
-version = "1.0.4"
+name = "pallet-chain-extension-dapps-staking"
+version = "1.1.0"
 authors = ["Stake Technologies <devops@stake.co.jp>"]
 edition = "2021"
 license = "Apache-2.0"
@@ -23,9 +23,8 @@ sp-runtime = { git = "https://github.com/paritytech/substrate", branch = "polkad
 sp-std = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.29", default-features = false }
 
 # Astar
-chain-extension-trait = { path = "../trait", default-features = false }
 dapps-staking-chain-extension-types = { path = "../types/dapps-staking", default-features = false }
-pallet-dapps-staking = { path = "../../frame/dapps-staking", default-features = false }
+pallet-dapps-staking = { git = "https://github.com/AstarNetwork/astar-frame", branch = "polkadot-v0.9.29", default-features = false }
 
 [features]
 default = ["std"]
diff --git a/chain-extensions/dapps-staking/src/lib.rs b/chain-extensions/dapps-staking/src/lib.rs
index 863db5c8..5e746300 100644
--- a/chain-extensions/dapps-staking/src/lib.rs
+++ b/chain-extensions/dapps-staking/src/lib.rs
@@ -4,16 +4,15 @@ use sp_runtime::{
     DispatchError,
 };
 
-use chain_extension_trait::ChainExtensionExec;
-use codec::{Decode, Encode};
+use codec::Encode;
 use dapps_staking_chain_extension_types::{
-    Contract, DSError, DappsStakingAccountInput, DappsStakingEraInput, DappsStakingNominationInput,
+    DSError, DappsStakingAccountInput, DappsStakingEraInput, DappsStakingNominationInput,
     DappsStakingValueInput,
 };
 use frame_support::traits::{Currency, Get};
 use frame_system::RawOrigin;
 use pallet_contracts::chain_extension::{
-    Environment, Ext, InitState, RetVal, SysConfig, UncheckedFrom,
+    ChainExtension, Environment, Ext, InitState, RetVal, SysConfig, UncheckedFrom,
 };
 use pallet_dapps_staking::{RewardDestination, WeightInfo};
 use sp_std::marker::PhantomData;
@@ -39,10 +38,10 @@ enum DappsStakingFunc {
     NominationTransfer,
 }
 
-impl TryFrom<u32> for DappsStakingFunc {
+impl TryFrom<u16> for DappsStakingFunc {
     type Error = DispatchError;
 
-    fn try_from(value: u32) -> Result<Self, Self::Error> {
+    fn try_from(value: u16) -> Result<Self, Self::Error> {
         match value {
             1 => Ok(DappsStakingFunc::CurrentEra),
             2 => Ok(DappsStakingFunc::UnbondingPeriod),
@@ -65,19 +64,27 @@ impl TryFrom<u32> for DappsStakingFunc {
     }
 }
 
-pub struct DappsStakingExtension<R>(PhantomData<R>);
+/// Dapps Staking chain extension.
+pub struct DappsStakingExtension<T>(PhantomData<T>);
 
-impl<T: pallet_dapps_staking::Config> ChainExtensionExec<T> for DappsStakingExtension<T> {
-    fn execute_func<E>(
-        func_id: u32,
-        env: Environment<E, InitState>,
-    ) -> Result<RetVal, DispatchError>
+impl<T> Default for DappsStakingExtension<T> {
+    fn default() -> Self {
+        DappsStakingExtension(PhantomData)
+    }
+}
+
+impl<T> ChainExtension<T> for DappsStakingExtension<T>
+where
+    T: pallet_dapps_staking::Config + pallet_contracts::Config,
+    <T as pallet_dapps_staking::Config>::SmartContract: From<[u8; 32]>,
+    <T as SysConfig>::AccountId: From<[u8; 32]>,
+{
+    fn call<E: Ext>(&mut self, env: Environment<E, InitState>) -> Result<RetVal, DispatchError>
     where
         E: Ext<T = T>,
-        <E::T as SysConfig>::AccountId:
-            UncheckedFrom<<E::T as SysConfig>::Hash> + AsRef<[u8]> + From<[u8; 32]>,
+        <E::T as SysConfig>::AccountId: UncheckedFrom<<E::T as SysConfig>::Hash> + AsRef<[u8]>,
     {
-        let func_id = DappsStakingFunc::try_from(func_id)?;
+        let func_id = env.func_id().try_into()?;
         let mut env = env.buf_in_buf_out();
 
         match func_id {
@@ -133,8 +140,9 @@ impl<T: pallet_dapps_staking::Config> ChainExtensionExec<T> for DappsStakingExte
 
             DappsStakingFunc::StakedAmountOnContract => {
                 let args: DappsStakingAccountInput = env.read_as()?;
-                let staker = T::AccountId::decode(&mut args.staker.as_ref()).unwrap();
-                let contract = Self::decode_smart_contract(args.contract)?;
+                let staker: T::AccountId = args.staker.into();
+                let contract: <T as pallet_dapps_staking::Config>::SmartContract =
+                    args.contract.into();
 
                 let base_weight = <T as frame_system::Config>::DbWeight::get().reads(1);
                 env.charge_weight(base_weight)?;
@@ -147,7 +155,8 @@ impl<T: pallet_dapps_staking::Config> ChainExtensionExec<T> for DappsStakingExte
 
             DappsStakingFunc::ReadContractStake => {
                 let contract_bytes: [u8; 32] = env.read_as()?;
-                let contract = Self::decode_smart_contract(contract_bytes)?;
+                let contract: <T as pallet_dapps_staking::Config>::SmartContract =
+                    contract_bytes.into();
 
                 let base_weight = <T as frame_system::Config>::DbWeight::get().reads(1);
                 env.charge_weight(base_weight.saturating_add(base_weight))?;
@@ -162,7 +171,7 @@ impl<T: pallet_dapps_staking::Config> ChainExtensionExec<T> for DappsStakingExte
 
             DappsStakingFunc::BondAndStake => {
                 let args: DappsStakingValueInput<BalanceOf<T>> = env.read_as()?;
-                let contract = Self::decode_smart_contract(args.contract)?;
+                let contract = args.contract.into();
                 let value: BalanceOf<T> = args.value;
 
                 let base_weight = <T as pallet_dapps_staking::Config>::WeightInfo::bond_and_stake();
@@ -185,7 +194,7 @@ impl<T: pallet_dapps_staking::Config> ChainExtensionExec<T> for DappsStakingExte
 
             DappsStakingFunc::UnbondAndUnstake => {
                 let args: DappsStakingValueInput<BalanceOf<T>> = env.read_as()?;
-                let contract = Self::decode_smart_contract(args.contract)?;
+                let contract = args.contract.into();
                 let value: BalanceOf<T> = args.value;
 
                 let base_weight =
@@ -228,10 +237,10 @@ impl<T: pallet_dapps_staking::Config> ChainExtensionExec<T> for DappsStakingExte
 
             DappsStakingFunc::ClaimStaker => {
                 let contract_bytes: [u8; 32] = env.read_as()?;
-                let contract = Self::decode_smart_contract(contract_bytes)?;
+                let contract = contract_bytes.into();
 
-                let base_weight = T::WeightInfo::claim_staker_with_restake()
-                    .max(T::WeightInfo::claim_staker_without_restake());
+                let base_weight = <T as pallet_dapps_staking::Config>::WeightInfo::claim_staker_with_restake()
+                    .max(<T as pallet_dapps_staking::Config>::WeightInfo::claim_staker_without_restake());
                 let charged_weight = env.charge_weight(base_weight)?;
 
                 let caller = env.ext().address().clone();
@@ -259,7 +268,7 @@ impl<T: pallet_dapps_staking::Config> ChainExtensionExec<T> for DappsStakingExte
 
             DappsStakingFunc::ClaimDapp => {
                 let args: DappsStakingEraInput = env.read_as()?;
-                let contract = Self::decode_smart_contract(args.contract)?;
+                let contract = args.contract.into();
                 let era: u32 = args.era;
 
                 let base_weight = <T as pallet_dapps_staking::Config>::WeightInfo::claim_dapp();
@@ -313,8 +322,8 @@ impl<T: pallet_dapps_staking::Config> ChainExtensionExec<T> for DappsStakingExte
 
             DappsStakingFunc::NominationTransfer => {
                 let args: DappsStakingNominationInput<BalanceOf<T>> = env.read_as()?;
-                let origin_smart_contract = Self::decode_smart_contract(args.origin_contract)?;
-                let target_smart_contract = Self::decode_smart_contract(args.target_contract)?;
+                let origin_smart_contract = args.origin_contract.into();
+                let target_smart_contract = args.target_contract.into();
                 let value: BalanceOf<T> = args.value;
 
                 let base_weight =
@@ -341,33 +350,3 @@ impl<T: pallet_dapps_staking::Config> ChainExtensionExec<T> for DappsStakingExte
         Ok(RetVal::Converging(DSError::Success as u32))
     }
 }
-
-impl<R> DappsStakingExtension<R> {
-    /// Helper method to decode type SmartContract enum
-    pub fn decode_smart_contract(
-        contract_bytes: [u8; 32],
-    ) -> Result<<R as pallet_dapps_staking::Config>::SmartContract, DispatchError>
-    where
-        R: pallet_dapps_staking::Config,
-        R::AccountId: From<[u8; 32]>,
-    {
-        let account: R::AccountId = contract_bytes.into();
-        // Encode contract address to fit SmartContract enum.
-        // Since the SmartContract enum type can't be accessed from this chain extension,
-        // use locally defined enum clone (see Contract enum)
-        let contract_enum_encoded = Contract::<R::AccountId>::Wasm(account).encode();
-
-        // encoded enum will add one byte before the contract's address
-        // therefore we need to decode len(u32) + 1 byte = 33
-        let smart_contract = <R as pallet_dapps_staking::Config>::SmartContract::decode(
-            &mut &contract_enum_encoded[..33],
-        )
-        .map_err(|_| {
-            DispatchError::Other(
-                "[ChainExtension] Error while decoding SmartContract in ChainExtension",
-            )
-        })?;
-
-        Ok(smart_contract)
-    }
-}
diff --git a/chain-extensions/rmrk/Cargo.toml b/chain-extensions/rmrk/Cargo.toml
index 7798919b..0d2b6c6a 100644
--- a/chain-extensions/rmrk/Cargo.toml
+++ b/chain-extensions/rmrk/Cargo.toml
@@ -24,7 +24,6 @@ sp-runtime = { git = "https://github.com/paritytech/substrate", branch = "polkad
 sp-std = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.29", default-features = false }
 
 # RMRK
-chain-extension-trait = { path = "../trait", default-features = false }
 pallet-rmrk-core = { git = "https://github.com/AstarNetwork/rmrk-substrate", branch = "polkadot-v0.9.29", default-features = false }
 rmrk-chain-extension-types = { path = "../types/rmrk", default-features = false }
 rmrk-traits = { git = "https://github.com/AstarNetwork/rmrk-substrate", branch = "polkadot-v0.9.29", default-features = false }
@@ -33,7 +32,6 @@ rmrk-traits = { git = "https://github.com/AstarNetwork/rmrk-substrate", branch =
 default = ["std"]
 std = [
 	"codec/std",
-	"chain-extension-trait/std",
 	"frame-support/std",
 	"frame-system/std",
 	"num-traits/std",
diff --git a/chain-extensions/rmrk/src/lib.rs b/chain-extensions/rmrk/src/lib.rs
index 71f2e5a6..6ccabb21 100644
--- a/chain-extensions/rmrk/src/lib.rs
+++ b/chain-extensions/rmrk/src/lib.rs
@@ -2,13 +2,12 @@
 
 use sp_runtime::{traits::StaticLookup, DispatchError, Permill};
 
-use chain_extension_trait::ChainExtensionExec;
-
 use codec::Encode;
 use frame_support::{log, weights::Weight, BoundedVec};
 use frame_system::RawOrigin;
 use pallet_contracts::chain_extension::{
-    Environment, Ext, InitState, RetVal, RetVal::Converging, SysConfig, UncheckedFrom,
+    ChainExtension, Environment, Ext, InitState, RetVal, RetVal::Converging, SysConfig,
+    UncheckedFrom,
 };
 use pallet_rmrk_core::{BoundedResourceInfoTypeOf, StringLimitOf};
 use rmrk_chain_extension_types::{RmrkError, RmrkFunc};
@@ -18,23 +17,27 @@ use rmrk_traits::{
 };
 use sp_std::{marker::PhantomData, vec::Vec};
 
-pub struct RmrkExtension<R>(PhantomData<R>);
+/// RMRK chain extension.
+pub struct RmrkExtension<T>(PhantomData<T>);
 
-impl<
-        T: pallet_rmrk_core::Config
-            + pallet_uniques::Config<CollectionId = CollectionId, ItemId = NftId>,
-    > ChainExtensionExec<T> for RmrkExtension<T>
+impl<T> Default for RmrkExtension<T> {
+    fn default() -> Self {
+        RmrkExtension(PhantomData)
+    }
+}
+
+impl<T> ChainExtension<T> for RmrkExtension<T>
+where
+    T: pallet_contracts::Config
+        + pallet_rmrk_core::Config
+        + pallet_uniques::Config<CollectionId = CollectionId, ItemId = NftId>,
 {
-    fn execute_func<E>(
-        func_id: u32,
-        env: Environment<E, InitState>,
-    ) -> Result<RetVal, DispatchError>
+    fn call<E: Ext>(&mut self, env: Environment<E, InitState>) -> Result<RetVal, DispatchError>
     where
         E: Ext<T = T>,
         <E::T as SysConfig>::AccountId: UncheckedFrom<<E::T as SysConfig>::Hash> + AsRef<[u8]>,
     {
-        let func_id = RmrkFunc::try_from(func_id)?;
-
+        let func_id = env.func_id().try_into()?;
         match func_id {
             // READ functions
             RmrkFunc::CollectionIndex => {
diff --git a/chain-extensions/trait/Cargo.toml b/chain-extensions/trait/Cargo.toml
deleted file mode 100644
index 95d42b98..00000000
--- a/chain-extensions/trait/Cargo.toml
+++ /dev/null
@@ -1,20 +0,0 @@
-[package]
-name = "chain-extension-trait"
-version = "1.0.3"
-authors = ["Stake Technologies <devops@stake.co.jp>"]
-edition = "2021"
-license = "Apache-2.0"
-homepage = "https://astar.network"
-repository = "https://github.com/AstarNetwork/astar-frame"
-description = "Trait definition for chain extension for WASM contracts"
-
-[dependencies]
-pallet-contracts = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.29", default-features = false, features = ["unstable-interface"] }
-sp-runtime = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.29", default-features = false }
-
-[features]
-default = ["std"]
-std = [
-	"pallet-contracts/std",
-	"sp-runtime/std",
-]
diff --git a/chain-extensions/trait/src/lib.rs b/chain-extensions/trait/src/lib.rs
deleted file mode 100644
index c3ced39f..00000000
--- a/chain-extensions/trait/src/lib.rs
+++ /dev/null
@@ -1,21 +0,0 @@
-#![cfg_attr(not(feature = "std"), no_std)]
-use pallet_contracts::chain_extension::{
-    Environment, Ext, InitState, RetVal, SysConfig, UncheckedFrom,
-};
-use sp_runtime::DispatchError;
-
-/// A Trait used to implement a chain-extension for a pallet
-///
-/// To create a chain-extension for a pallet this trait must be implemented
-///
-/// T is the Config trait of the pallet
-pub trait ChainExtensionExec<T: SysConfig> {
-    fn execute_func<E>(
-        func_id: u32,
-        env: Environment<E, InitState>,
-    ) -> Result<RetVal, DispatchError>
-    where
-        E: Ext<T = T>,
-        <E::T as SysConfig>::AccountId:
-            UncheckedFrom<<E::T as SysConfig>::Hash> + AsRef<[u8]> + From<[u8; 32]>;
-}
diff --git a/chain-extensions/types/dapps-staking/Cargo.toml b/chain-extensions/types/dapps-staking/Cargo.toml
index 400df664..ebb8befb 100644
--- a/chain-extensions/types/dapps-staking/Cargo.toml
+++ b/chain-extensions/types/dapps-staking/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "dapps-staking-chain-extension-types"
-version = "1.0.2"
+version = "1.1.0"
 authors = ["Stake Technologies <devops@stake.co.jp>"]
 edition = "2021"
 license = "Apache-2.0"
diff --git a/chain-extensions/types/dapps-staking/src/lib.rs b/chain-extensions/types/dapps-staking/src/lib.rs
index 4123e896..3bfc6328 100644
--- a/chain-extensions/types/dapps-staking/src/lib.rs
+++ b/chain-extensions/types/dapps-staking/src/lib.rs
@@ -1,7 +1,6 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 use codec::{Decode, Encode};
 use frame_support::pallet_prelude::MaxEncodedLen;
-use sp_core::H160;
 use sp_runtime::{DispatchError, ModuleError};
 
 #[cfg_attr(feature = "std", derive(scale_info::TypeInfo))]
@@ -111,15 +110,6 @@ impl TryFrom<DispatchError> for DSError {
     }
 }
 
-/// This is only used to encode SmartContract enum
-#[derive(PartialEq, Eq, Copy, Clone, Encode, Decode, Debug)]
-pub enum Contract<Account> {
-    // EVM smart contract instance.
-    Evm(H160),
-    // Wasm smart contract instance. Not used in this precompile
-    Wasm(Account),
-}
-
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Encode, Decode, MaxEncodedLen)]
 pub struct DappsStakingValueInput<Balance> {
     pub contract: [u8; 32],
diff --git a/chain-extensions/types/rmrk/src/lib.rs b/chain-extensions/types/rmrk/src/lib.rs
index 58cccbce..86129a45 100644
--- a/chain-extensions/types/rmrk/src/lib.rs
+++ b/chain-extensions/types/rmrk/src/lib.rs
@@ -38,10 +38,10 @@ pub enum RmrkFunc {
     SetPriority,
 }
 
-impl TryFrom<u32> for RmrkFunc {
+impl TryFrom<u16> for RmrkFunc {
     type Error = DispatchError;
 
-    fn try_from(value: u32) -> Result<Self, Self::Error> {
+    fn try_from(value: u16) -> Result<Self, Self::Error> {
         return match value {
             // getters
             // 0x0001 => Ok(RmrkFunc::NextNftId),
diff --git a/chain-extensions/xvm/Cargo.toml b/chain-extensions/xvm/Cargo.toml
index 291f52e1..a06ac9b8 100644
--- a/chain-extensions/xvm/Cargo.toml
+++ b/chain-extensions/xvm/Cargo.toml
@@ -1,5 +1,5 @@
 [package]
-name = "xvm-chain-extension"
+name = "pallet-chain-extension-xvm"
 version = "0.1.0"
 authors = ["Stake Technologies <devops@stake.co.jp>"]
 edition = "2021"
@@ -23,7 +23,6 @@ sp-runtime = { git = "https://github.com/paritytech/substrate", branch = "polkad
 sp-std = { git = "https://github.com/paritytech/substrate", branch = "polkadot-v0.9.29", default-features = false }
 
 # Astar
-chain-extension-trait = { path = "../trait", default-features = false }
 pallet-xvm = { path = "../../frame/pallet-xvm", default-features = false }
 xvm-chain-extension-types = { path = "../types/xvm", default-features = false }
 
diff --git a/chain-extensions/xvm/src/lib.rs b/chain-extensions/xvm/src/lib.rs
index c20cd470..5aac13cf 100644
--- a/chain-extensions/xvm/src/lib.rs
+++ b/chain-extensions/xvm/src/lib.rs
@@ -3,12 +3,12 @@
 use frame_support::weights::Weight;
 use frame_system::RawOrigin;
 use pallet_contracts::chain_extension::{
-    Environment, Ext, InitState, RetVal, SysConfig, UncheckedFrom,
+    ChainExtension, Environment, Ext, InitState, RetVal, SysConfig, UncheckedFrom,
 };
 use pallet_xvm::XvmContext;
 use sp_runtime::DispatchError;
+use sp_std::marker::PhantomData;
 
-use chain_extension_trait::ChainExtensionExec;
 use xvm_chain_extension_types::{XvmCallArgs, XvmExecutionResult};
 
 enum XvmFuncId {
@@ -16,10 +16,10 @@ enum XvmFuncId {
     // TODO: expand with other calls too
 }
 
-impl TryFrom<u32> for XvmFuncId {
+impl TryFrom<u16> for XvmFuncId {
     type Error = DispatchError;
 
-    fn try_from(value: u32) -> Result<Self, Self::Error> {
+    fn try_from(value: u16) -> Result<Self, Self::Error> {
         match value {
             1 => Ok(XvmFuncId::XvmCall),
             _ => Err(DispatchError::Other(
@@ -29,21 +29,25 @@ impl TryFrom<u32> for XvmFuncId {
     }
 }
 
-pub struct XvmExtension;
+/// XVM chain extension.
+pub struct XvmExtension<T>(PhantomData<T>);
 
-impl<T> ChainExtensionExec<T> for XvmExtension
+impl<T> Default for XvmExtension<T> {
+    fn default() -> Self {
+        XvmExtension(PhantomData)
+    }
+}
+
+impl<T> ChainExtension<T> for XvmExtension<T>
 where
     T: pallet_contracts::Config + pallet_xvm::Config,
 {
-    fn execute_func<E>(
-        func_id: u32,
-        env: Environment<'_, '_, E, InitState>,
-    ) -> Result<RetVal, DispatchError>
+    fn call<E: Ext>(&mut self, env: Environment<E, InitState>) -> Result<RetVal, DispatchError>
     where
         E: Ext<T = T>,
         <E::T as SysConfig>::AccountId: UncheckedFrom<<E::T as SysConfig>::Hash> + AsRef<[u8]>,
     {
-        let func_id: XvmFuncId = func_id.try_into()?;
+        let func_id = env.func_id().try_into()?;
         let mut env = env.buf_in_buf_out();
 
         match func_id {