One node two runtimes (#191)

* One node two runtimes This enables the rococo-collator to run the normal and the contracts runtime. * Fix tests
2026-05-30 09:21:04 +00:00 · 2020-08-11 11:35:54 +02:00
parent 3ed6030110
commit 3b71c2a6e2
33 changed files with 1958 additions and 1466 deletions
@@ -976,6 +976,7 @@ dependencies = [
 "parachain-info",
 "parity-scale-codec",
 "polkadot-parachain",
+ "rococo-parachain-primitives",
 "serde",
 "sp-api",
 "sp-block-builder",
@@ -1213,6 +1214,7 @@ dependencies = [
 "parachain-info",
 "parity-scale-codec",
 "polkadot-parachain",
+ "rococo-parachain-primitives",
 "serde",
 "sp-api",
 "sp-block-builder",
@@ -5831,6 +5833,7 @@ dependencies = [
 "polkadot-test-runtime-client",
 "polkadot-test-service",
 "rand 0.7.3",
+ "rococo-parachain-primitives",
 "sc-basic-authorship",
 "sc-chain-spec",
 "sc-cli",
@@ -5840,15 +5843,20 @@ dependencies = [
 "sc-finality-grandpa",
 "sc-informant",
 "sc-network",
+ "sc-rpc",
 "sc-service",
 "sc-transaction-pool",
 "serde",
 "sp-api",
+ "sp-block-builder",
+ "sp-blockchain",
 "sp-consensus",
 "sp-core",
 "sp-inherents",
 "sp-io",
+ "sp-offchain",
 "sp-runtime",
+ "sp-session",
 "sp-timestamp",
 "sp-transaction-pool",
 "sp-trie",
@@ -5860,6 +5868,14 @@ dependencies = [
 "trie-root 0.15.2",
 ]

+[[package]]
+name = "rococo-parachain-primitives"
+version = "0.1.0"
+dependencies = [
+ "sp-core",
+ "sp-runtime",
+]
+
 [[package]]
 name = "rococo-runtime"
 version = "0.8.22"
@@ -9,6 +9,7 @@ members = [
 	"rococo-parachains/contracts-runtime",
 	"rococo-parachains/pallets/parachain-info",
 	"rococo-parachains/pallets/token-dealer",
+	"rococo-parachains/primitives",
 	"rococo-parachains/runtime",
 	"runtime",
 	"service",
@@ -518,8 +518,7 @@ where
 				Box::new(self.polkadot_network.clone()),
 			)));

-		let follow =
-			match cumulus_consensus::follow_polkadot(
+		let follow = match cumulus_consensus::follow_polkadot(
 			self.para_id,
 			self.client,
 			polkadot_client,
@@ -23,7 +23,10 @@ mod tests;

 use sp_api::ProvideRuntimeApi;
 use sp_blockchain::{Error as ClientError, HeaderBackend};
-use sp_consensus::{block_validation::{BlockAnnounceValidator, Validation}, SyncOracle};
+use sp_consensus::{
+	block_validation::{BlockAnnounceValidator, Validation},
+	SyncOracle,
+};
 use sp_core::traits::SpawnNamed;
 use sp_runtime::{
 	generic::BlockId,
@@ -17,9 +17,9 @@
 use super::*;
 use cumulus_test_runtime::{Block, Header};
 use polkadot_primitives::v0::{
-	AbridgedCandidateReceipt, Chain, CollatorId, DutyRoster, GlobalValidationData,
-	Id as ParaId, LocalValidationData, ParachainHost, Retriable, SigningContext,
-	ValidationCode, ValidatorId, Block as PBlock, Hash as PHash, Header as PHeader,
+	AbridgedCandidateReceipt, Block as PBlock, Chain, CollatorId, DutyRoster, GlobalValidationData,
+	Hash as PHash, Header as PHeader, Id as ParaId, LocalValidationData, ParachainHost, Retriable,
+	SigningContext, ValidationCode, ValidatorId,
 };
 use polkadot_test_runtime_client::{
 	DefaultTestClientBuilderExt, TestClient, TestClientBuilder, TestClientBuilderExt,
@@ -25,6 +25,7 @@ hex-literal = "0.2.1"
 # Parachain dependencies
 parachain-runtime = { package = "cumulus-test-parachain-runtime", path = "runtime" }
 parachain-contracts-runtime = { package = "cumulus-contracts-parachain-runtime", path = "contracts-runtime" }
+rococo-parachain-primitives = { path = "primitives" }

 # Substrate dependencies
 sp-runtime = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "rococo-branch" }
@@ -32,6 +33,7 @@ sp-io = { git = "https://github.com/paritytech/substrate", branch = "rococo-bran
 sp-core = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sp-inherents = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sp-consensus = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
+sp-session = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sc-consensus = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sc-cli = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sc-client-api = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
@@ -42,11 +44,15 @@ sp-transaction-pool = { git = "https://github.com/paritytech/substrate", branch
 sc-network = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sc-basic-authorship = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch", version = "0.8.0-rc5" }
 sp-timestamp = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
+sp-blockchain = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
+sp-block-builder = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sp-trie = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sp-api = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sc-finality-grandpa = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sc-informant = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
 sc-chain-spec = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
+sc-rpc = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }
+sp-offchain = { git = "https://github.com/paritytech/substrate", branch = "rococo-branch" }

 # RPC related dependencies
 cumulus-pallet-contracts-rpc = { path = "./pallets/contracts/rpc" }
@@ -10,6 +10,7 @@ codec = { package = "parity-scale-codec", version = "1.3.0", default-features =

 cumulus-token-dealer = { path = "../pallets/token-dealer", default-features = false}
 parachain-info = { path = "../pallets/parachain-info", default-features = false}
+rococo-parachain-primitives = { path = "../primitives", default-features = false}

 # Substrate dependencies
 sp-std = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "rococo-branch" }
@@ -79,6 +80,7 @@ std = [
 	"pallet-sudo/std",
 	"pallet-transaction-payment/std",
 	"parachain-info/std",
+	"rococo-parachain-primitives/std",
 	"cumulus-runtime/std",
 	"cumulus-parachain-upgrade/std",
 	"cumulus-message-broker/std",
@@ -23,13 +23,14 @@
 include!(concat!(env!("OUT_DIR"), "/wasm_binary.rs"));

 use cumulus_pallet_contracts_rpc_runtime_api::ContractExecResult;
+use rococo_parachain_primitives::*;
 use sp_api::impl_runtime_apis;
 use sp_core::OpaqueMetadata;
 use sp_runtime::{
 	create_runtime_str, generic, impl_opaque_keys,
-	traits::{BlakeTwo256, Block as BlockT, IdentifyAccount, IdentityLookup, Saturating, Verify},
+	traits::{BlakeTwo256, Block as BlockT, IdentityLookup, Saturating},
 	transaction_validity::{TransactionSource, TransactionValidity},
-	ApplyExtrinsicResult, MultiSignature,
+	ApplyExtrinsicResult,
 };
 use sp_std::prelude::*;
 #[cfg(feature = "std")]
@@ -49,61 +50,18 @@ pub use pallet_timestamp::Call as TimestampCall;
 pub use sp_runtime::BuildStorage;
 pub use sp_runtime::{Perbill, Permill};

-/// An index to a block.
-pub type BlockNumber = u32;
-
-/// Alias to 512-bit hash when used in the context of a transaction signature on the chain.
-pub type Signature = MultiSignature;
-
-/// Some way of identifying an account on the chain. We intentionally make it equivalent
-/// to the public key of our transaction signing scheme.
-pub type AccountId = <<Signature as Verify>::Signer as IdentifyAccount>::AccountId;
-
-/// The type for looking up accounts. We don't expect more than 4 billion of them, but you
-/// never know...
-pub type AccountIndex = u32;
-
-/// Balance of an account.
-pub type Balance = u128;
-
-/// Index of a transaction in the chain.
-pub type Index = u32;
-
-/// A hash of some data used by the chain.
-pub type Hash = sp_core::H256;
-
-/// Digest item type.
-pub type DigestItem = generic::DigestItem<Hash>;
-
-/// 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
-/// of data like extrinsics, allowing for them to continue syncing the network through upgrades
-/// to even the core datastructures.
-pub mod opaque {
-	use super::*;
-
-	pub use sp_runtime::OpaqueExtrinsic as UncheckedExtrinsic;
-
-	/// Opaque block header type.
-	pub type Header = generic::Header<BlockNumber, BlakeTwo256>;
-	/// Opaque block type.
-	pub type Block = generic::Block<Header, UncheckedExtrinsic>;
-	/// Opaque block identifier type.
-	pub type BlockId = generic::BlockId<Block>;
-
 pub type SessionHandlers = ();

 impl_opaque_keys! {
 	pub struct SessionKeys {}
 }
-}

 /// This runtime version.
 pub const VERSION: RuntimeVersion = RuntimeVersion {
 	spec_name: create_runtime_str!("cumulus-contracts-parachain"),
 	impl_name: create_runtime_str!("cumulus-contracts-parachain"),
 	authoring_version: 1,
-	spec_version: 1,
+	spec_version: 2,
 	impl_version: 1,
 	apis: RUNTIME_API_VERSIONS,
 	transaction_version: 1,
@@ -292,7 +250,7 @@ impl cumulus_pallet_contracts::Trait for Runtime {
 construct_runtime! {
 	pub enum Runtime where
 		Block = Block,
-		NodeBlock = opaque::Block,
+		NodeBlock = rococo_parachain_primitives::Block,
 		UncheckedExtrinsic = UncheckedExtrinsic
 	{
 		System: frame_system::{Module, Call, Storage, Config, Event<T>},
@@ -405,11 +363,11 @@ impl_runtime_apis! {
 		fn decode_session_keys(
 			encoded: Vec<u8>,
 		) -> Option<Vec<(Vec<u8>, sp_core::crypto::KeyTypeId)>> {
-			opaque::SessionKeys::decode_into_raw_public_keys(&encoded)
+			SessionKeys::decode_into_raw_public_keys(&encoded)
 		}

 		fn generate_session_keys(seed: Option<Vec<u8>>) -> Vec<u8> {
-			opaque::SessionKeys::generate(seed)
+			SessionKeys::generate(seed)
 		}
 	}

@@ -20,9 +20,9 @@
 use std::sync::Arc;

 use codec::Codec;
+use cumulus_pallet_contracts_primitives::RentProjection;
 use jsonrpc_core::{Error, ErrorCode, Result};
 use jsonrpc_derive::rpc;
-use cumulus_pallet_contracts_primitives::RentProjection;
 use serde::{Deserialize, Serialize};
 use sp_api::ProvideRuntimeApi;
 use sp_blockchain::HeaderBackend;
@@ -106,7 +106,11 @@ pub enum RpcContractExecResult {
 impl From<ContractExecResult> for RpcContractExecResult {
 	fn from(r: ContractExecResult) -> Self {
 		match r {
-			ContractExecResult::Success { flags, data, gas_consumed } => RpcContractExecResult::Success {
+			ContractExecResult::Success {
+				flags,
+				data,
+				gas_consumed,
+			} => RpcContractExecResult::Success {
 				flags,
 				data: data.into(),
 				gas_consumed,
@@ -293,7 +297,8 @@ mod tests {
 	#[test]
 	fn call_request_should_serialize_deserialize_properly() {
 		type Req = CallRequest<String, u128>;
-		let req: Req = serde_json::from_str(r#"
+		let req: Req = serde_json::from_str(
+			r#"
 		{
 			"origin": "5CiPPseXPECbkjWCa6MnjNokrgYjMqmKndv2rSnekmSK2DjL",
 			"dest": "5DRakbLVnjVrW6niwLfHGW24EeCEvDAFGEXrtaYS5M4ynoom",
@@ -301,7 +306,9 @@ mod tests {
 			"gasLimit": 1000000000000,
 			"inputData": "0x8c97db39"
 		}
-		"#).unwrap();
+		"#,
+		)
+		.unwrap();
 		assert_eq!(req.gas_limit.into_u256(), U256::from(0xe8d4a51000u64));
 	}

@@ -21,14 +21,19 @@ use super::{
 	TrieIdGenerator,
 };
 use crate::exec::StorageKey;
-use sp_std::cell::RefCell;
-use sp_std::collections::btree_map::{BTreeMap, Entry};
-use sp_std::prelude::*;
+use frame_support::{
+	storage::unhashed as storage,
+	traits::{Currency, Imbalance, SignedImbalance},
+	StorageMap,
+};
+use frame_system;
 use sp_io::hashing::blake2_256;
 use sp_runtime::traits::{Bounded, Zero};
-use frame_support::traits::{Currency, Imbalance, SignedImbalance};
-use frame_support::{storage::unhashed as storage, StorageMap};
-use frame_system;
+use sp_std::{
+	cell::RefCell,
+	collections::btree_map::{BTreeMap, Entry},
+	prelude::*,
+};

 // Note: we don't provide Option<Contract> because we can't create
 // the trie_id in the overlay, thus we provide an overlay on the fields
@@ -133,8 +138,7 @@ impl<T: Trait> AccountDb<T> for DirectAccountDb {
 		trie_id: Option<&TrieId>,
 		location: &StorageKey,
 	) -> Option<Vec<u8>> {
-		trie_id
-			.and_then(|id| storage::get_raw(&crate::prefixed_key(id, &blake2_256(location))))
+		trie_id.and_then(|id| storage::get_raw(&crate::prefixed_key(id, &blake2_256(location))))
 	}
 	fn get_code_hash(&self, account: &T::AccountId) -> Option<CodeHash<T>> {
 		<ContractInfoOf<T>>::get(account).and_then(|i| i.as_alive().map(|i| i.code_hash))
@@ -241,13 +245,13 @@ impl<T: Trait> AccountDb<T> for DirectAccountDb {
 							if prev_value.is_empty() {
 								new_info.empty_pair_count -= 1;
 							}
-						},
+						}
 						(None, Some(new_value)) => {
 							new_info.total_pair_count += 1;
 							if new_value.is_empty() {
 								new_info.empty_pair_count += 1;
 							}
-						},
+						}
 						(Some(prev_value), Some(new_value)) => {
 							if prev_value.is_empty() {
 								new_info.empty_pair_count -= 1;
@@ -14,19 +14,23 @@
 // You should have received a copy of the GNU General Public License
 // along with Substrate. If not, see <http://www.gnu.org/licenses/>.

-use super::{CodeHash, Config, ContractAddressFor, Event, RawEvent, Trait,
-	TrieId, BalanceOf, ContractInfo};
-use crate::account_db::{AccountDb, DirectAccountDb, OverlayAccountDb};
-use crate::gas::{Gas, GasMeter, Token};
-use crate::rent;
+use super::{
+	BalanceOf, CodeHash, Config, ContractAddressFor, ContractInfo, Event, RawEvent, Trait, TrieId,
+};
+use crate::{
+	account_db::{AccountDb, DirectAccountDb, OverlayAccountDb},
+	gas::{Gas, GasMeter, Token},
+	rent,
+};

-use sp_std::prelude::*;
-use sp_runtime::traits::{Bounded, Zero, Convert, CheckedSub, CheckedAdd};
 use frame_support::{
-	storage::unhashed, dispatch::DispatchError,
-	traits::{Currency, Time, Randomness, WithdrawReason},
+	dispatch::DispatchError,
+	storage::unhashed,
+	traits::{Currency, Randomness, Time, WithdrawReason},
 	weights::Weight,
 };
+use sp_runtime::traits::{Bounded, CheckedAdd, CheckedSub, Convert, Zero};
+use sp_std::prelude::*;

 pub type AccountIdOf<T> = <T as frame_system::Trait>::AccountId;
 pub type CallOf<T> = <T as Trait>::Call;
@@ -84,11 +88,14 @@ macro_rules! try_or_exec_error {
 	($e:expr, $buffer:expr) => {
 		match $e {
 			Ok(val) => val,
-			Err(reason) => return Err(
-				$crate::exec::ExecError { reason: reason.into(), buffer: $buffer }
-			),
+			Err(reason) => {
+				return Err($crate::exec::ExecError {
+					reason: reason.into(),
+					buffer: $buffer,
+				})
 				}
 			}
+	};
 }

 /// An interface that provides access to the external environment in which the
@@ -332,9 +339,11 @@ where
 		}
 	}

-	fn nested<'b, 'c: 'b>(&'c self, dest: T::AccountId, trie_id: Option<TrieId>)
-		-> ExecutionContext<'b, T, V, L>
-	{
+	fn nested<'b, 'c: 'b>(
+		&'c self,
+		dest: T::AccountId,
+		trie_id: Option<TrieId>,
+	) -> ExecutionContext<'b, T, V, L> {
 		ExecutionContext {
 			caller: Some(self),
 			self_trie_id: trie_id,
@@ -355,7 +364,7 @@ where
 		&mut self,
 		dest: T::AccountId,
 		value: BalanceOf<T>,
-		gas_meter: &mut GasMeter<T>
+		gas_meter: &mut GasMeter<T>,
 	) -> Result<(), DispatchError> {
 		transfer(
 			gas_meter,
@@ -427,12 +436,9 @@ where
 			// it is a regular account since tombstone accounts have already been rejected.
 			match nested.overlay.get_code_hash(&dest) {
 				Some(dest_code_hash) => {
-					let executable = try_or_exec_error!(
-						nested.loader.load_main(&dest_code_hash),
-						input_data
-					);
-					let output = nested.vm
-						.execute(
+					let executable =
+						try_or_exec_error!(nested.loader.load_main(&dest_code_hash), input_data);
+					let output = nested.vm.execute(
 						&executable,
 						nested.new_call_context(caller, value),
 						input_data,
@@ -441,7 +447,10 @@ where

 					Ok(output)
 				}
-				None => Ok(ExecReturnValue { status: STATUS_SUCCESS, data: Vec::new() }),
+				None => Ok(ExecReturnValue {
+					status: STATUS_SUCCESS,
+					data: Vec::new(),
+				}),
 			}
 		})
 	}
@@ -471,18 +480,17 @@ where
 		}

 		let caller = self.self_account.clone();
-		let dest = T::DetermineContractAddress::contract_address_for(
-			code_hash,
-			&input_data,
-			&caller,
-		);
+		let dest =
+			T::DetermineContractAddress::contract_address_for(code_hash, &input_data, &caller);

 		// TrieId has not been generated yet and storage is empty since contract is new.
 		let dest_trie_id = None;

 		let output = self.with_nested_context(dest.clone(), dest_trie_id, |nested| {
 			try_or_exec_error!(
-				nested.overlay.instantiate_contract(&dest, code_hash.clone()),
+				nested
+					.overlay
+					.instantiate_contract(&dest, code_hash.clone()),
 				input_data
 			);

@@ -500,12 +508,8 @@ where
 				input_data
 			);

-			let executable = try_or_exec_error!(
-				nested.loader.load_init(&code_hash),
-				input_data
-			);
-			let output = nested.vm
-				.execute(
+			let executable = try_or_exec_error!(nested.loader.load_init(&code_hash), input_data);
+			let output = nested.vm.execute(
 				&executable,
 				nested.new_call_context(caller.clone(), endowment),
 				input_data,
@@ -574,9 +578,14 @@ where
 		}
 	}

-	fn with_nested_context<F>(&mut self, dest: T::AccountId, trie_id: Option<TrieId>, func: F)
-		-> ExecResult
-		where F: FnOnce(&mut ExecutionContext<T, V, L>) -> ExecResult
+	fn with_nested_context<F>(
+		&mut self,
+		dest: T::AccountId,
+		trie_id: Option<TrieId>,
+		func: F,
+	) -> ExecResult
+	where
+		F: FnOnce(&mut ExecutionContext<T, V, L>) -> ExecResult,
 	{
 		let (output, change_set, deferred) = {
 			let mut nested = self.nested(dest, trie_id);
@@ -595,8 +604,7 @@ where
 	/// Returns whether a contract, identified by address, is currently live in the execution
 	/// stack, meaning it is in the middle of an execution.
 	fn is_live(&self, account: &T::AccountId) -> bool {
-		&self.self_account == account ||
-			self.caller.map_or(false, |caller| caller.is_live(account))
+		&self.self_account == account || self.caller.map_or(false, |caller| caller.is_live(account))
 	}
 }

@@ -656,8 +664,7 @@ fn transfer<'a, T: Trait, V: Vm<T>, L: Loader<T>>(
 	value: BalanceOf<T>,
 	ctx: &mut ExecutionContext<'a, T, V, L>,
 ) -> Result<(), DispatchError> {
-	use self::TransferCause::*;
-	use self::TransferFeeKind::*;
+	use self::{TransferCause::*, TransferFeeKind::*};

 	let token = {
 		let kind: TransferFeeKind = match cause {
@@ -668,9 +675,7 @@ fn transfer<'a, T: Trait, V: Vm<T>, L: Loader<T>>(
 			// Otherwise the fee is to transfer to an account.
 			Call | Terminate => TransferFeeKind::Transfer,
 		};
-		TransferFeeToken {
-			kind,
-		}
+		TransferFeeToken { kind }
 	};

 	if gas_meter.charge(ctx.config, token).is_out_of_gas() {
@@ -691,14 +696,15 @@ fn transfer<'a, T: Trait, V: Vm<T>, L: Loader<T>>(
 	// Only ext_terminate is allowed to bring the sender below the existential deposit
 	let required_balance = match cause {
 		Terminate => 0.into(),
-		_ => ctx.config.existential_deposit
+		_ => ctx.config.existential_deposit,
 	};

 	T::Currency::ensure_can_withdraw(
 		transactor,
 		value,
 		WithdrawReason::Transfer.into(),
-		new_from_balance.checked_sub(&required_balance)
+		new_from_balance
+			.checked_sub(&required_balance)
 			.ok_or("brings sender below existential deposit")?,
 	)?;

@@ -736,7 +742,9 @@ where
 	type T = T;

 	fn get_storage(&self, key: &StorageKey) -> Option<Vec<u8>> {
-		self.ctx.overlay.get_storage(&self.ctx.self_account, self.ctx.self_trie_id.as_ref(), key)
+		self.ctx
+			.overlay
+			.get_storage(&self.ctx.self_account, self.ctx.self_trie_id.as_ref(), key)
 	}

 	fn set_storage(&mut self, key: StorageKey, value: Option<Vec<u8>>) -> Result<(), &'static str> {
@@ -759,7 +767,8 @@ where
 		gas_meter: &mut GasMeter<T>,
 		input_data: Vec<u8>,
 	) -> Result<(AccountIdOf<T>, ExecReturnValue), ExecError> {
-		self.ctx.instantiate(endowment, gas_meter, code_hash, input_data)
+		self.ctx
+			.instantiate(endowment, gas_meter, code_hash, input_data)
 	}

 	fn transfer(
@@ -852,15 +861,21 @@ where
 	}

 	fn set_rent_allowance(&mut self, rent_allowance: BalanceOf<T>) {
-		self.ctx.overlay.set_rent_allowance(&self.ctx.self_account, rent_allowance)
+		self.ctx
+			.overlay
+			.set_rent_allowance(&self.ctx.self_account, rent_allowance)
 	}

 	fn rent_allowance(&self) -> BalanceOf<T> {
-		self.ctx.overlay.get_rent_allowance(&self.ctx.self_account)
+		self.ctx
+			.overlay
+			.get_rent_allowance(&self.ctx.self_account)
 			.unwrap_or(<BalanceOf<T>>::max_value()) // Must never be triggered actually
 	}

-	fn block_number(&self) -> T::BlockNumber { self.block_number }
+	fn block_number(&self) -> T::BlockNumber {
+		self.block_number
+	}

 	fn max_value_size(&self) -> u32 {
 		self.ctx.config.max_value_size
@@ -888,17 +903,19 @@ where
 #[cfg(test)]
 mod tests {
 	use super::{
-		BalanceOf, ExecFeeToken, ExecutionContext, Ext, Loader, TransferFeeKind, TransferFeeToken,
-		Vm, ExecResult, RawEvent, DeferredAction,
+		BalanceOf, DeferredAction, ExecFeeToken, ExecResult, ExecutionContext, Ext, Loader,
+		RawEvent, TransferFeeKind, TransferFeeToken, Vm,
 	};
 	use crate::{
-		account_db::AccountDb, gas::GasMeter, tests::{ExtBuilder, Test},
-		exec::{ExecReturnValue, ExecError, STATUS_SUCCESS}, CodeHash, Config,
-		gas::Gas,
+		account_db::AccountDb,
+		exec::{ExecError, ExecReturnValue, STATUS_SUCCESS},
+		gas::{Gas, GasMeter},
+		tests::{ExtBuilder, Test},
+		CodeHash, Config,
 	};
-	use std::{cell::RefCell, rc::Rc, collections::HashMap, marker::PhantomData};
 	use assert_matches::assert_matches;
 	use sp_runtime::DispatchError;
+	use std::{cell::RefCell, collections::HashMap, marker::PhantomData, rc::Rc};

 	const ALICE: u64 = 1;
 	const BOB: u64 = 2;
@@ -907,7 +924,8 @@ mod tests {
 	const GAS_LIMIT: Gas = 10_000_000_000;

 	impl<'a, T, V, L> ExecutionContext<'a, T, V, L>
-		where T: crate::Trait
+	where
+		T: crate::Trait,
 	{
 		fn events(&self) -> Vec<DeferredAction<T>> {
 			self.deferred
@@ -965,7 +983,9 @@ mod tests {

 	impl<'a> MockVm<'a> {
 		fn new() -> Self {
-			MockVm { _marker: PhantomData }
+			MockVm {
+				_marker: PhantomData,
+			}
 		}
 	}

@@ -1005,7 +1025,10 @@ mod tests {
 	}

 	fn exec_success() -> ExecResult {
-		Ok(ExecReturnValue { status: STATUS_SUCCESS, data: Vec::new() })
+		Ok(ExecReturnValue {
+			status: STATUS_SUCCESS,
+			data: Vec::new(),
+		})
 	}

 	#[test]
@@ -1029,10 +1052,7 @@ mod tests {
 			let mut ctx = ExecutionContext::top_level(ALICE, &cfg, &vm, &loader);
 			ctx.overlay.instantiate_contract(&BOB, exec_ch).unwrap();

-			assert_matches!(
-				ctx.call(BOB, value, &mut gas_meter, data),
-				Ok(_)
-			);
+			assert_matches!(ctx.call(BOB, value, &mut gas_meter, data), Ok(_));
 		});

 		assert_eq!(&*test_data.borrow(), &vec![0, 1]);
@@ -1098,12 +1118,9 @@ mod tests {
 			ctx.overlay.set_balance(&origin, 100);
 			ctx.overlay.set_balance(&dest, 0);

-			let output = ctx.call(
-				dest,
-				55,
-				&mut GasMeter::<Test>::new(GAS_LIMIT),
-				vec![],
-			).unwrap();
+			let output = ctx
+				.call(dest, 55, &mut GasMeter::<Test>::new(GAS_LIMIT), vec![])
+				.unwrap();

 			assert!(output.is_success());
 			assert_eq!(ctx.overlay.get_balance(&origin), 45);
@@ -1120,9 +1137,12 @@ mod tests {

 		let vm = MockVm::new();
 		let mut loader = MockLoader::empty();
-		let return_ch = loader.insert(
-			|_| Ok(ExecReturnValue { status: 1, data: Vec::new() })
-		);
+		let return_ch = loader.insert(|_| {
+			Ok(ExecReturnValue {
+				status: 1,
+				data: Vec::new(),
+			})
+		});

 		ExtBuilder::default().build().execute_with(|| {
 			let cfg = Config::preload();
@@ -1131,12 +1151,9 @@ mod tests {
 			ctx.overlay.set_balance(&origin, 100);
 			ctx.overlay.set_balance(&dest, 0);

-			let output = ctx.call(
-				dest,
-				55,
-				&mut GasMeter::<Test>::new(GAS_LIMIT),
-				vec![],
-			).unwrap();
+			let output = ctx
+				.call(dest, 55, &mut GasMeter::<Test>::new(GAS_LIMIT), vec![])
+				.unwrap();

 			assert!(!output.is_success());
 			assert_eq!(ctx.overlay.get_balance(&origin), 100);
@@ -1152,7 +1169,10 @@ mod tests {
 		// This test sends 50 units of currency to a non-existent account.
 		// This should lead to creation of a new account thus
 		// a fee should be charged.
-		ExtBuilder::default().existential_deposit(15).build().execute_with(|| {
+		ExtBuilder::default()
+			.existential_deposit(15)
+			.build()
+			.execute_with(|| {
 				let vm = MockVm::new();
 				let loader = MockLoader::empty();
 				let cfg = Config::preload();
@@ -1177,7 +1197,10 @@ mod tests {

 		// This one is similar to the previous one but transfer to an existing account.
 		// In this test we expect that a regular transfer fee is charged.
-		ExtBuilder::default().existential_deposit(15).build().execute_with(|| {
+		ExtBuilder::default()
+			.existential_deposit(15)
+			.build()
+			.execute_with(|| {
 				let vm = MockVm::new();
 				let loader = MockLoader::empty();
 				let cfg = Config::preload();
@@ -1202,7 +1225,10 @@ mod tests {

 		// This test sends 50 units of currency as an endowment to a newly
 		// instantiated contract.
-		ExtBuilder::default().existential_deposit(15).build().execute_with(|| {
+		ExtBuilder::default()
+			.existential_deposit(15)
+			.build()
+			.execute_with(|| {
 				let mut loader = MockLoader::empty();
 				let code = loader.insert(|_| exec_success());

@@ -1244,12 +1270,7 @@ mod tests {
 			let mut ctx = ExecutionContext::top_level(origin, &cfg, &vm, &loader);
 			ctx.overlay.set_balance(&origin, 0);

-			let result = ctx.call(
-				dest,
-				100,
-				&mut GasMeter::<Test>::new(GAS_LIMIT),
-				vec![],
-			);
+			let result = ctx.call(dest, 100, &mut GasMeter::<Test>::new(GAS_LIMIT), vec![]);

 			assert_matches!(
 				result,
@@ -1272,21 +1293,19 @@ mod tests {

 		let vm = MockVm::new();
 		let mut loader = MockLoader::empty();
-		let return_ch = loader.insert(
-			|_| Ok(ExecReturnValue { status: STATUS_SUCCESS, data: vec![1, 2, 3, 4] })
-		);
+		let return_ch = loader.insert(|_| {
+			Ok(ExecReturnValue {
+				status: STATUS_SUCCESS,
+				data: vec![1, 2, 3, 4],
+			})
+		});

 		ExtBuilder::default().build().execute_with(|| {
 			let cfg = Config::preload();
 			let mut ctx = ExecutionContext::top_level(origin, &cfg, &vm, &loader);
 			ctx.overlay.instantiate_contract(&BOB, return_ch).unwrap();

-			let result = ctx.call(
-				dest,
-				0,
-				&mut GasMeter::<Test>::new(GAS_LIMIT),
-				vec![],
-			);
+			let result = ctx.call(dest, 0, &mut GasMeter::<Test>::new(GAS_LIMIT), vec![]);

 			let output = result.unwrap();
 			assert!(output.is_success());
@@ -1303,21 +1322,19 @@ mod tests {

 		let vm = MockVm::new();
 		let mut loader = MockLoader::empty();
-		let return_ch = loader.insert(
-			|_| Ok(ExecReturnValue { status: 1, data: vec![1, 2, 3, 4] })
-		);
+		let return_ch = loader.insert(|_| {
+			Ok(ExecReturnValue {
+				status: 1,
+				data: vec![1, 2, 3, 4],
+			})
+		});

 		ExtBuilder::default().build().execute_with(|| {
 			let cfg = Config::preload();
 			let mut ctx = ExecutionContext::top_level(origin, &cfg, &vm, &loader);
 			ctx.overlay.instantiate_contract(&BOB, return_ch).unwrap();

-			let result = ctx.call(
-				dest,
-				0,
-				&mut GasMeter::<Test>::new(GAS_LIMIT),
-				vec![],
-			);
+			let result = ctx.call(dest, 0, &mut GasMeter::<Test>::new(GAS_LIMIT), vec![]);

 			let output = result.unwrap();
 			assert!(!output.is_success());
@@ -1338,7 +1355,9 @@ mod tests {
 		ExtBuilder::default().build().execute_with(|| {
 			let cfg = Config::preload();
 			let mut ctx = ExecutionContext::top_level(ALICE, &cfg, &vm, &loader);
-			ctx.overlay.instantiate_contract(&BOB, input_data_ch).unwrap();
+			ctx.overlay
+				.instantiate_contract(&BOB, input_data_ch)
+				.unwrap();

 			let result = ctx.call(
 				BOB,
@@ -1415,12 +1434,7 @@ mod tests {
 			ctx.overlay.set_balance(&BOB, 1);
 			ctx.overlay.instantiate_contract(&BOB, recurse_ch).unwrap();

-			let result = ctx.call(
-				BOB,
-				value,
-				&mut GasMeter::<Test>::new(GAS_LIMIT),
-				vec![],
-			);
+			let result = ctx.call(BOB, value, &mut GasMeter::<Test>::new(GAS_LIMIT), vec![]);

 			assert_matches!(result, Ok(_));
 		});
@@ -1442,10 +1456,7 @@ mod tests {
 			*witnessed_caller_bob.borrow_mut() = Some(*ctx.ext.caller());

 			// Call into CHARLIE contract.
-			assert_matches!(
-				ctx.ext.call(&CHARLIE, 0, ctx.gas_meter, vec![]),
-				Ok(_)
-			);
+			assert_matches!(ctx.ext.call(&CHARLIE, 0, ctx.gas_meter, vec![]), Ok(_));
 			exec_success()
 		});
 		let charlie_ch = loader.insert(|ctx| {
@@ -1459,14 +1470,11 @@ mod tests {

 			let mut ctx = ExecutionContext::top_level(origin, &cfg, &vm, &loader);
 			ctx.overlay.instantiate_contract(&dest, bob_ch).unwrap();
-			ctx.overlay.instantiate_contract(&CHARLIE, charlie_ch).unwrap();
+			ctx.overlay
+				.instantiate_contract(&CHARLIE, charlie_ch)
+				.unwrap();

-			let result = ctx.call(
-				dest,
-				0,
-				&mut GasMeter::<Test>::new(GAS_LIMIT),
-				vec![],
-			);
+			let result = ctx.call(dest, 0, &mut GasMeter::<Test>::new(GAS_LIMIT), vec![]);

 			assert_matches!(result, Ok(_));
 		});
@@ -1485,10 +1493,7 @@ mod tests {
 			assert_eq!(*ctx.ext.address(), BOB);

 			// Call into charlie contract.
-			assert_matches!(
-				ctx.ext.call(&CHARLIE, 0, ctx.gas_meter, vec![]),
-				Ok(_)
-			);
+			assert_matches!(ctx.ext.call(&CHARLIE, 0, ctx.gas_meter, vec![]), Ok(_));
 			exec_success()
 		});
 		let charlie_ch = loader.insert(|ctx| {
@@ -1500,14 +1505,11 @@ mod tests {
 			let cfg = Config::preload();
 			let mut ctx = ExecutionContext::top_level(ALICE, &cfg, &vm, &loader);
 			ctx.overlay.instantiate_contract(&BOB, bob_ch).unwrap();
-			ctx.overlay.instantiate_contract(&CHARLIE, charlie_ch).unwrap();
+			ctx.overlay
+				.instantiate_contract(&CHARLIE, charlie_ch)
+				.unwrap();

-			let result = ctx.call(
-				BOB,
-				0,
-				&mut GasMeter::<Test>::new(GAS_LIMIT),
-				vec![],
-			);
+			let result = ctx.call(BOB, 0, &mut GasMeter::<Test>::new(GAS_LIMIT), vec![]);

 			assert_matches!(result, Ok(_));
 		});
@@ -1520,7 +1522,10 @@ mod tests {
 		let mut loader = MockLoader::empty();
 		let dummy_ch = loader.insert(|_| exec_success());

-		ExtBuilder::default().existential_deposit(15).build().execute_with(|| {
+		ExtBuilder::default()
+			.existential_deposit(15)
+			.build()
+			.execute_with(|| {
 				let cfg = Config::preload();
 				let mut ctx = ExecutionContext::top_level(ALICE, &cfg, &vm, &loader);

@@ -1541,11 +1546,17 @@ mod tests {
 		let vm = MockVm::new();

 		let mut loader = MockLoader::empty();
-		let dummy_ch = loader.insert(
-			|_| Ok(ExecReturnValue { status: STATUS_SUCCESS, data: vec![80, 65, 83, 83] })
-		);
+		let dummy_ch = loader.insert(|_| {
+			Ok(ExecReturnValue {
+				status: STATUS_SUCCESS,
+				data: vec![80, 65, 83, 83],
+			})
+		});

-		ExtBuilder::default().existential_deposit(15).build().execute_with(|| {
+		ExtBuilder::default()
+			.existential_deposit(15)
+			.build()
+			.execute_with(|| {
 				let cfg = Config::preload();
 				let mut ctx = ExecutionContext::top_level(ALICE, &cfg, &vm, &loader);
 				ctx.overlay.set_balance(&ALICE, 1000);
@@ -1562,8 +1573,15 @@ mod tests {

 				// Check that the newly created account has the expected code hash and
 				// there are instantiation event.
-			assert_eq!(ctx.overlay.get_code_hash(&instantiated_contract_address).unwrap(), dummy_ch);
-			assert_eq!(&ctx.events(), &[
+				assert_eq!(
+					ctx.overlay
+						.get_code_hash(&instantiated_contract_address)
+						.unwrap(),
+					dummy_ch
+				);
+				assert_eq!(
+					&ctx.events(),
+					&[
 						DeferredAction::DepositEvent {
 							event: RawEvent::Transfer(ALICE, instantiated_contract_address, 100),
 							topics: Vec::new(),
@@ -1572,7 +1590,8 @@ mod tests {
 							event: RawEvent::Instantiated(ALICE, instantiated_contract_address),
 							topics: Vec::new(),
 						}
-			]);
+					]
+				);
 			});
 	}

@@ -1581,11 +1600,17 @@ mod tests {
 		let vm = MockVm::new();

 		let mut loader = MockLoader::empty();
-		let dummy_ch = loader.insert(
-			|_| Ok(ExecReturnValue { status: 1, data: vec![70, 65, 73, 76] })
-		);
+		let dummy_ch = loader.insert(|_| {
+			Ok(ExecReturnValue {
+				status: 1,
+				data: vec![70, 65, 73, 76],
+			})
+		});

-		ExtBuilder::default().existential_deposit(15).build().execute_with(|| {
+		ExtBuilder::default()
+			.existential_deposit(15)
+			.build()
+			.execute_with(|| {
 				let cfg = Config::preload();
 				let mut ctx = ExecutionContext::top_level(ALICE, &cfg, &vm, &loader);
 				ctx.overlay.set_balance(&ALICE, 1000);
@@ -1601,7 +1626,10 @@ mod tests {
 				);

 				// Check that the account has not been created.
-			assert!(ctx.overlay.get_code_hash(&instantiated_contract_address).is_none());
+				assert!(ctx
+					.overlay
+					.get_code_hash(&instantiated_contract_address)
+					.is_none());
 				assert!(ctx.events().is_empty());
 			});
 	}
@@ -1618,36 +1646,50 @@ mod tests {
 			let instantiated_contract_address = Rc::clone(&instantiated_contract_address);
 			move |ctx| {
 				// Instantiate a contract and save it's address in `instantiated_contract_address`.
-				let (address, output) = ctx.ext.instantiate(
-					&dummy_ch,
-					15u64,
-					ctx.gas_meter,
-					vec![]
-				).unwrap();
+				let (address, output) = ctx
+					.ext
+					.instantiate(&dummy_ch, 15u64, ctx.gas_meter, vec![])
+					.unwrap();

 				*instantiated_contract_address.borrow_mut() = address.into();
 				Ok(output)
 			}
 		});

-		ExtBuilder::default().existential_deposit(15).build().execute_with(|| {
+		ExtBuilder::default()
+			.existential_deposit(15)
+			.build()
+			.execute_with(|| {
 				let cfg = Config::preload();
 				let mut ctx = ExecutionContext::top_level(ALICE, &cfg, &vm, &loader);
 				ctx.overlay.set_balance(&ALICE, 1000);
 				ctx.overlay.set_balance(&BOB, 100);
-			ctx.overlay.instantiate_contract(&BOB, instantiator_ch).unwrap();
+				ctx.overlay
+					.instantiate_contract(&BOB, instantiator_ch)
+					.unwrap();

 				assert_matches!(
 					ctx.call(BOB, 20, &mut GasMeter::<Test>::new(GAS_LIMIT), vec![]),
 					Ok(_)
 				);

-			let instantiated_contract_address = instantiated_contract_address.borrow().as_ref().unwrap().clone();
+				let instantiated_contract_address = instantiated_contract_address
+					.borrow()
+					.as_ref()
+					.unwrap()
+					.clone();

 				// Check that the newly created account has the expected code hash and
 				// there are instantiation event.
-			assert_eq!(ctx.overlay.get_code_hash(&instantiated_contract_address).unwrap(), dummy_ch);
-			assert_eq!(&ctx.events(), &[
+				assert_eq!(
+					ctx.overlay
+						.get_code_hash(&instantiated_contract_address)
+						.unwrap(),
+					dummy_ch
+				);
+				assert_eq!(
+					&ctx.events(),
+					&[
 						DeferredAction::DepositEvent {
 							event: RawEvent::Transfer(ALICE, BOB, 20),
 							topics: Vec::new(),
@@ -1660,7 +1702,8 @@ mod tests {
 							event: RawEvent::Instantiated(BOB, instantiated_contract_address),
 							topics: Vec::new(),
 						},
-			]);
+					]
+				);
 			});
 	}

@@ -1669,33 +1712,39 @@ mod tests {
 		let vm = MockVm::new();

 		let mut loader = MockLoader::empty();
-		let dummy_ch = loader.insert(
-			|_| Err(ExecError { reason: "It's a trap!".into(), buffer: Vec::new() })
-		);
+		let dummy_ch = loader.insert(|_| {
+			Err(ExecError {
+				reason: "It's a trap!".into(),
+				buffer: Vec::new(),
+			})
+		});
 		let instantiator_ch = loader.insert({
 			let dummy_ch = dummy_ch.clone();
 			move |ctx| {
 				// Instantiate a contract and save it's address in `instantiated_contract_address`.
 				assert_matches!(
-					ctx.ext.instantiate(
-						&dummy_ch,
-						15u64,
-						ctx.gas_meter,
-						vec![]
-					),
-					Err(ExecError { reason: DispatchError::Other("It's a trap!"), buffer: _ })
+					ctx.ext.instantiate(&dummy_ch, 15u64, ctx.gas_meter, vec![]),
+					Err(ExecError {
+						reason: DispatchError::Other("It's a trap!"),
+						buffer: _,
+					})
 				);

 				exec_success()
 			}
 		});

-		ExtBuilder::default().existential_deposit(15).build().execute_with(|| {
+		ExtBuilder::default()
+			.existential_deposit(15)
+			.build()
+			.execute_with(|| {
 				let cfg = Config::preload();
 				let mut ctx = ExecutionContext::top_level(ALICE, &cfg, &vm, &loader);
 				ctx.overlay.set_balance(&ALICE, 1000);
 				ctx.overlay.set_balance(&BOB, 100);
-			ctx.overlay.instantiate_contract(&BOB, instantiator_ch).unwrap();
+				ctx.overlay
+					.instantiate_contract(&BOB, instantiator_ch)
+					.unwrap();

 				assert_matches!(
 					ctx.call(BOB, 20, &mut GasMeter::<Test>::new(GAS_LIMIT), vec![]),
@@ -1704,12 +1753,13 @@ mod tests {

 				// The contract wasn't instantiated so we don't expect to see an instantiation
 				// event here.
-			assert_eq!(&ctx.events(), &[
-				DeferredAction::DepositEvent {
+				assert_eq!(
+					&ctx.events(),
+					&[DeferredAction::DepositEvent {
 						event: RawEvent::Transfer(ALICE, BOB, 20),
 						topics: Vec::new(),
-				},
-			]);
+					},]
+				);
 			});
 	}

@@ -1745,10 +1795,7 @@ mod tests {
 					}) if buffer == Vec::<u8>::new()
 				);

-				assert_eq!(
-					&ctx.events(),
-					&[]
-				);
+				assert_eq!(&ctx.events(), &[]);
 			});
 	}

@@ -15,11 +15,11 @@
 // along with Substrate. If not, see <http://www.gnu.org/licenses/>.

 use crate::Trait;
-use sp_std::marker::PhantomData;
-use sp_runtime::traits::Zero;
 use frame_support::dispatch::{
-	DispatchError, DispatchResultWithPostInfo, PostDispatchInfo, DispatchErrorWithPostInfo,
+	DispatchError, DispatchErrorWithPostInfo, DispatchResultWithPostInfo, PostDispatchInfo,
 };
+use sp_runtime::traits::Zero;
+use sp_std::marker::PhantomData;

 #[cfg(test)]
 use std::{any::Any, fmt::Debug};
@@ -189,7 +189,8 @@ impl<T: Trait> GasMeter<T> {
 	}

 	/// Turn this GasMeter into a DispatchResult that contains the actually used gas.
-	pub fn into_dispatch_result<R, E>(self, result: Result<R, E>) -> DispatchResultWithPostInfo where
+	pub fn into_dispatch_result<R, E>(self, result: Result<R, E>) -> DispatchResultWithPostInfo
+	where
 		E: Into<DispatchError>,
 	{
 		let post_info = PostDispatchInfo {
@@ -199,7 +200,10 @@ impl<T: Trait> GasMeter<T> {

 		result
 			.map(|_| post_info)
-			.map_err(|e| DispatchErrorWithPostInfo { post_info, error: e.into() })
+			.map_err(|e| DispatchErrorWithPostInfo {
+				post_info,
+				error: e.into(),
+			})
 	}

 	#[cfg(test)]
@@ -256,7 +260,9 @@ mod tests {
 	struct SimpleToken(u64);
 	impl Token<Test> for SimpleToken {
 		type Metadata = ();
-		fn calculate_amount(&self, _metadata: &()) -> u64 { self.0 }
+		fn calculate_amount(&self, _metadata: &()) -> u64 {
+			self.0
+		}
 	}

 	struct MultiplierTokenMetadata {
@@ -285,8 +291,10 @@ mod tests {
 	fn simple() {
 		let mut gas_meter = GasMeter::<Test>::new(50000);

-		let result = gas_meter
-			.charge(&MultiplierTokenMetadata { multiplier: 3 }, MultiplierToken(10));
+		let result = gas_meter.charge(
+			&MultiplierTokenMetadata { multiplier: 3 },
+			MultiplierToken(10),
+		);
 		assert!(!result.is_out_of_gas());

 		assert_eq!(gas_meter.gas_left(), 49_970);
@@ -297,7 +305,10 @@ mod tests {
 		let mut gas_meter = GasMeter::<Test>::new(50000);
 		assert!(!gas_meter.charge(&(), SimpleToken(1)).is_out_of_gas());
 		assert!(!gas_meter
-			.charge(&MultiplierTokenMetadata { multiplier: 3 }, MultiplierToken(10))
+			.charge(
+				&MultiplierTokenMetadata { multiplier: 3 },
+				MultiplierToken(10)
+			)
 			.is_out_of_gas());

 		let mut tokens = gas_meter.tokens()[0..2].iter();
@@ -327,7 +338,6 @@ mod tests {
 		assert!(gas_meter.charge(&(), SimpleToken(1)).is_out_of_gas());
 	}

-
 	// Charging the exact amount that the user paid for should be
 	// possible.
 	#[test]
@@ -84,42 +84,42 @@ mod gas;

 mod account_db;
 mod exec;
-mod wasm;
 mod rent;
+mod wasm;

 #[cfg(test)]
 mod tests;

-use crate::exec::ExecutionContext;
-use crate::account_db::{AccountDb, DirectAccountDb};
-use crate::wasm::{WasmLoader, WasmVm};
+use crate::{
+	account_db::{AccountDb, DirectAccountDb},
+	exec::ExecutionContext,
+	wasm::{WasmLoader, WasmVm},
+};

-pub use crate::gas::{Gas, GasMeter};
-pub use crate::exec::{ExecResult, ExecReturnValue, ExecError, StatusCode};
+pub use crate::{
+	exec::{ExecError, ExecResult, ExecReturnValue, StatusCode},
+	gas::{Gas, GasMeter},
+};

+use codec::{Codec, Decode, Encode};
+use cumulus_pallet_contracts_primitives::{ContractAccessError, RentProjection};
+use frame_support::{
+	decl_error, decl_event, decl_module, decl_storage,
+	dispatch::{DispatchResult, DispatchResultWithPostInfo, Dispatchable, PostDispatchInfo},
+	parameter_types,
+	traits::{Currency, Get, OnUnbalanced, Randomness, Time},
+	weights::{GetDispatchInfo, Weight},
+	Parameter,
+};
+use frame_system::{ensure_root, ensure_signed, RawOrigin};
 #[cfg(feature = "std")]
-use serde::{Serialize, Deserialize};
+use serde::{Deserialize, Serialize};
 use sp_core::crypto::UncheckedFrom;
-use sp_std::{prelude::*, marker::PhantomData, fmt::Debug};
-use codec::{Codec, Encode, Decode};
 use sp_runtime::{
-	traits::{
-		Hash, StaticLookup, Zero, MaybeSerializeDeserialize, Member, Convert,
-	},
+	traits::{Convert, Hash, MaybeSerializeDeserialize, Member, StaticLookup, Zero},
 	RuntimeDebug,
 };
-use frame_support::dispatch::{
-	PostDispatchInfo, DispatchResult, Dispatchable, DispatchResultWithPostInfo
-};
-use frame_support::{
-	Parameter, decl_module, decl_event, decl_storage, decl_error,
-	parameter_types,
-};
-use frame_support::traits::{OnUnbalanced, Currency, Get, Time, Randomness};
-use frame_support::weights::GetDispatchInfo;
-use frame_system::{ensure_signed, RawOrigin, ensure_root};
-use cumulus_pallet_contracts_primitives::{RentProjection, ContractAccessError};
-use frame_support::weights::Weight;
+use sp_std::{fmt::Debug, marker::PhantomData, prelude::*};

 pub type CodeHash<T> = <T as frame_system::Trait>::Hash;
 pub type TrieId = Vec<u8>;
@@ -240,9 +240,15 @@ pub struct RawTombstoneContractInfo<H, Hasher>(H, PhantomData<Hasher>);

 impl<H, Hasher> RawTombstoneContractInfo<H, Hasher>
 where
-	H: Member + MaybeSerializeDeserialize+ Debug
-		+ AsRef<[u8]> + AsMut<[u8]> + Copy + Default
-		+ sp_std::hash::Hash + Codec,
+	H: Member
+		+ MaybeSerializeDeserialize
+		+ Debug
+		+ AsRef<[u8]>
+		+ AsMut<[u8]>
+		+ Copy
+		+ Default
+		+ sp_std::hash::Hash
+		+ Codec,
 	Hasher: Hash<Output = H>,
 {
 	fn new(storage_root: &[u8], code_hash: H) -> Self {
@@ -272,7 +278,7 @@ pub struct TrieIdFromParentCounter<T: Trait>(PhantomData<T>);
 /// accountid_counter`.
 impl<T: Trait> TrieIdGenerator<T::AccountId> for TrieIdFromParentCounter<T>
 where
-	T::AccountId: AsRef<[u8]>
+	T::AccountId: AsRef<[u8]>,
 {
 	fn trie_id(account_id: &T::AccountId) -> TrieId {
 		// Note that skipping a value due to error is not an issue here.
@@ -321,10 +327,9 @@ pub trait Trait: frame_system::Trait {
 	type Currency: Currency<Self::AccountId>;

 	/// The outer call dispatch type.
-	type Call:
-		Parameter +
-		Dispatchable<PostInfo=PostDispatchInfo, Origin=<Self as frame_system::Trait>::Origin> +
-		GetDispatchInfo;
+	type Call: Parameter
+		+ Dispatchable<PostInfo = PostDispatchInfo, Origin = <Self as frame_system::Trait>::Origin>
+		+ GetDispatchInfo;

 	/// The overarching event type.
 	type Event: From<Event<Self>> + Into<<Self as frame_system::Trait>::Event>;
@@ -390,9 +395,13 @@ pub trait Trait: frame_system::Trait {
 pub struct SimpleAddressDeterminer<T: Trait>(PhantomData<T>);
 impl<T: Trait> ContractAddressFor<CodeHash<T>, T::AccountId> for SimpleAddressDeterminer<T>
 where
-	T::AccountId: UncheckedFrom<T::Hash> + AsRef<[u8]>
+	T::AccountId: UncheckedFrom<T::Hash> + AsRef<[u8]>,
 {
-	fn contract_address_for(code_hash: &CodeHash<T>, data: &[u8], origin: &T::AccountId) -> T::AccountId {
+	fn contract_address_for(
+		code_hash: &CodeHash<T>,
+		data: &[u8],
+		origin: &T::AccountId,
+	) -> T::AccountId {
 		let data_hash = T::Hashing::hash(data);

 		let mut buf = Vec::new();
@@ -641,13 +650,15 @@ impl<T: Trait> Module<T> {

 impl<T: Trait> Module<T> {
 	fn calc_code_put_costs(code: &Vec<u8>) -> Gas {
-		<Module<T>>::current_schedule().put_code_per_byte_cost.saturating_mul(code.len() as Gas)
+		<Module<T>>::current_schedule()
+			.put_code_per_byte_cost
+			.saturating_mul(code.len() as Gas)
 	}

 	fn execute_wasm(
 		origin: T::AccountId,
 		gas_meter: &mut GasMeter<T>,
-		func: impl FnOnce(&mut ExecutionContext<T, WasmVm, WasmLoader>, &mut GasMeter<T>) -> ExecResult
+		func: impl FnOnce(&mut ExecutionContext<T, WasmVm, WasmLoader>, &mut GasMeter<T>) -> ExecResult,
 	) -> ExecResult {
 		let cfg = Config::preload();
 		let vm = WasmVm::new(&cfg.schedule);
@@ -656,7 +667,11 @@ impl<T: Trait> Module<T> {

 		let result = func(&mut ctx, gas_meter);

-		if result.as_ref().map(|output| output.is_success()).unwrap_or(false) {
+		if result
+			.as_ref()
+			.map(|output| output.is_success())
+			.unwrap_or(false)
+		{
 			// Commit all changes that made it thus far into the persistent storage.
 			DirectAccountDb.commit(ctx.overlay.into_change_set());
 		}
@@ -665,17 +680,11 @@ impl<T: Trait> Module<T> {
 		ctx.deferred.into_iter().for_each(|deferred| {
 			use self::exec::DeferredAction::*;
 			match deferred {
-				DepositEvent {
-					topics,
-					event,
-				} => <frame_system::Module<T>>::deposit_event_indexed(
+				DepositEvent { topics, event } => <frame_system::Module<T>>::deposit_event_indexed(
 					&*topics,
 					<T as Trait>::Event::from(event).into(),
 				),
-				DispatchRuntimeCall {
-					origin: who,
-					call,
-				} => {
+				DispatchRuntimeCall { origin: who, call } => {
 					let info = call.get_dispatch_info();
 					let result = call.dispatch(RawOrigin::Signed(who.clone()).into());
 					let post_info = match result {
@@ -693,11 +702,19 @@ impl<T: Trait> Module<T> {
 					delta,
 				} => {
 					let result = Self::restore_to(
-						donor.clone(), dest.clone(), code_hash.clone(), rent_allowance.clone(), delta
-					);
-					Self::deposit_event(
-						RawEvent::Restored(donor, dest, code_hash, rent_allowance, result.is_ok())
+						donor.clone(),
+						dest.clone(),
+						code_hash.clone(),
+						rent_allowance.clone(),
+						delta,
 					);
+					Self::deposit_event(RawEvent::Restored(
+						donor,
+						dest,
+						code_hash,
+						rent_allowance,
+						result.is_ok(),
+					));
 				}
 			}
 		});
@@ -20,10 +20,14 @@ use crate::{
 	AliveContractInfo, BalanceOf, ContractInfo, ContractInfoOf, Module, RawEvent,
 	TombstoneContractInfo, Trait,
 };
-use frame_support::storage::unhashed as storage;
-use frame_support::traits::{Currency, ExistenceRequirement, Get, OnUnbalanced, WithdrawReason};
-use frame_support::StorageMap;
-use cumulus_pallet_contracts_primitives::{ContractAccessError, RentProjection, RentProjectionResult};
+use cumulus_pallet_contracts_primitives::{
+	ContractAccessError, RentProjection, RentProjectionResult,
+};
+use frame_support::{
+	storage::unhashed as storage,
+	traits::{Currency, ExistenceRequirement, Get, OnUnbalanced, WithdrawReason},
+	StorageMap,
+};
 use sp_runtime::traits::{Bounded, CheckedDiv, CheckedMul, SaturatedConversion, Saturating, Zero};

 /// The amount to charge.
@@ -238,10 +242,8 @@ fn enact_verdict<T: Trait>(

 			// Use a dummy storage root because restoration is currentlyy unsupported
 			// for parachains anyways.
-			let tombstone = <TombstoneContractInfo<T>>::new(
-				&[0u8; 32],
-				alive_contract_info.code_hash,
-			);
+			let tombstone =
+				<TombstoneContractInfo<T>>::new(&[0u8; 32], alive_contract_info.code_hash);
 			let tombstone_info = ContractInfo::Tombstone(tombstone);
 			<ContractInfoOf<T>>::insert(account, &tombstone_info);

@@ -26,11 +26,13 @@
 //! this guarantees that every instrumented contract code in cache cannot have the version equal to the current one.
 //! Thus, before executing a contract it should be reinstrument with new schedule.

-use crate::wasm::{prepare, runtime::Env, PrefabWasmModule};
-use crate::{CodeHash, CodeStorage, PristineCode, Schedule, Trait};
-use sp_std::prelude::*;
-use sp_runtime::traits::Hash;
+use crate::{
+	wasm::{prepare, runtime::Env, PrefabWasmModule},
+	CodeHash, CodeStorage, PristineCode, Schedule, Trait,
+};
 use frame_support::StorageMap;
+use sp_runtime::traits::Hash;
+use sp_std::prelude::*;

 /// Put code in the storage. The hash of code is used as a key and is returned
 /// as a result of this function.
@@ -58,8 +60,7 @@ pub fn load<T: Trait>(
 	code_hash: &CodeHash<T>,
 	schedule: &Schedule,
 ) -> Result<PrefabWasmModule, &'static str> {
-	let mut prefab_module =
-		<CodeStorage<T>>::get(code_hash).ok_or_else(|| "code is not found")?;
+	let mut prefab_module = <CodeStorage<T>>::get(code_hash).ok_or_else(|| "code is not found")?;

 	if prefab_module.schedule_version < schedule.version {
 		// The current schedule version is greater than the version of the one cached
@@ -193,14 +193,14 @@ macro_rules! define_env {

 #[cfg(test)]
 mod tests {
-	use parity_wasm::elements::FunctionType;
-	use parity_wasm::elements::ValueType;
+	use crate::{
+		exec::Ext,
+		gas::Gas,
+		wasm::{tests::MockExt, Runtime},
+	};
+	use parity_wasm::elements::{FunctionType, ValueType};
 	use sp_runtime::traits::Zero;
 	use sp_sandbox::{ReturnValue, Value};
-	use crate::wasm::tests::MockExt;
-	use crate::wasm::Runtime;
-	use crate::exec::Ext;
-	use crate::gas::Gas;

 	#[test]
 	fn macro_unmarshall_then_body_then_marshall_value_or_trap() {
@@ -263,8 +263,10 @@ mod tests {
 				Err(sp_sandbox::HostError)
 			}
 		});
-		let _f: fn(&mut Runtime<MockExt>, &[sp_sandbox::Value])
-			-> Result<sp_sandbox::ReturnValue, sp_sandbox::HostError> = ext_gas::<MockExt>;
+		let _f: fn(
+			&mut Runtime<MockExt>,
+			&[sp_sandbox::Value],
+		) -> Result<sp_sandbox::ReturnValue, sp_sandbox::HostError> = ext_gas::<MockExt>;
 	}

 	#[test]
@@ -317,7 +319,13 @@ mod tests {
 			},
 		);

-		assert!(Env::can_satisfy(b"ext_gas", &FunctionType::new(vec![ValueType::I32], None)));
-		assert!(!Env::can_satisfy(b"not_exists", &FunctionType::new(vec![], None)));
+		assert!(Env::can_satisfy(
+			b"ext_gas",
+			&FunctionType::new(vec![ValueType::I32], None)
+		));
+		assert!(!Env::can_satisfy(
+			b"not_exists",
+			&FunctionType::new(vec![], None)
+		));
 	}
 }
@@ -17,8 +17,8 @@
 use super::Runtime;
 use crate::exec::Ext;

-use sp_sandbox::Value;
 use parity_wasm::elements::{FunctionType, ValueType};
+use sp_sandbox::Value;

 #[macro_use]
 pub(crate) mod macros;
@@ -66,10 +66,9 @@ impl ConvertibleToWasm for u64 {
 	}
 }

-pub(crate) type HostFunc<E> =
-	fn(
+pub(crate) type HostFunc<E> = fn(
 	&mut Runtime<E>,
-		&[sp_sandbox::Value]
+	&[sp_sandbox::Value],
 ) -> Result<sp_sandbox::ReturnValue, sp_sandbox::HostError>;

 pub(crate) trait FunctionImplProvider<E: Ext> {
@@ -17,14 +17,16 @@
 //! This module provides a means for executing contracts
 //! represented in wasm.

-use crate::{CodeHash, Schedule, Trait};
-use crate::wasm::env_def::FunctionImplProvider;
-use crate::exec::{Ext, ExecResult};
-use crate::gas::GasMeter;
+use crate::{
+	exec::{ExecResult, Ext},
+	gas::GasMeter,
+	wasm::env_def::FunctionImplProvider,
+	CodeHash, Schedule, Trait,
+};

-use sp_std::prelude::*;
-use codec::{Encode, Decode};
+use codec::{Decode, Encode};
 use sp_sandbox;
+use sp_std::prelude::*;

 #[macro_use]
 mod env_def;
@@ -32,8 +34,10 @@ mod code_cache;
 mod prepare;
 mod runtime;

-use self::runtime::{to_execution_result, Runtime};
-use self::code_cache::load as load_code;
+use self::{
+	code_cache::load as load_code,
+	runtime::{to_execution_result, Runtime},
+};

 pub use self::code_cache::save as save_code;

@@ -131,13 +135,7 @@ impl<'a, T: Trait> crate::exec::Vm<T> for WasmVm<'a> {
 			imports.add_host_func("env", name, func_ptr);
 		});

-		let mut runtime = Runtime::new(
-			&mut ext,
-			input_data,
-			&self.schedule,
-			memory,
-			gas_meter,
-		);
+		let mut runtime = Runtime::new(&mut ext, input_data, &self.schedule, memory, gas_meter);

 		// Instantiate the instance from the instrumented module code and invoke the contract
 		// entrypoint.
@@ -150,19 +148,20 @@ impl<'a, T: Trait> crate::exec::Vm<T> for WasmVm<'a> {
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use std::collections::HashMap;
-	use std::cell::RefCell;
-	use sp_core::H256;
-	use crate::exec::{Ext, StorageKey, ExecError, ExecReturnValue, STATUS_SUCCESS};
-	use crate::gas::{Gas, GasMeter};
-	use crate::tests::{Test, Call};
-	use crate::wasm::prepare::prepare_contract;
-	use crate::{CodeHash, BalanceOf};
-	use wabt;
-	use hex_literal::hex;
+	use crate::{
+		exec::{ExecError, ExecReturnValue, Ext, StorageKey, STATUS_SUCCESS},
+		gas::{Gas, GasMeter},
+		tests::{Call, Test},
+		wasm::prepare::prepare_contract,
+		BalanceOf, CodeHash,
+	};
 	use assert_matches::assert_matches;
-	use sp_runtime::DispatchError;
 	use frame_support::weights::Weight;
+	use hex_literal::hex;
+	use sp_core::H256;
+	use sp_runtime::DispatchError;
+	use std::{cell::RefCell, collections::HashMap};
+	use wabt;

 	const GAS_LIMIT: Gas = 10_000_000_000;

@@ -230,9 +229,11 @@ mod tests {
 		fn get_storage(&self, key: &StorageKey) -> Option<Vec<u8>> {
 			self.storage.get(key).cloned()
 		}
-		fn set_storage(&mut self, key: StorageKey, value: Option<Vec<u8>>)
-			-> Result<(), &'static str>
-		{
+		fn set_storage(
+			&mut self,
+			key: StorageKey,
+			value: Option<Vec<u8>>,
+		) -> Result<(), &'static str> {
 			*self.storage.entry(key).or_insert(Vec::new()) = value.unwrap_or(Vec::new());
 			Ok(())
 		}
@@ -289,7 +290,10 @@ mod tests {
 			});
 			// Assume for now that it was just a plain transfer.
 			// TODO: Add tests for different call outcomes.
-			Ok(ExecReturnValue { status: STATUS_SUCCESS, data: Vec::new() })
+			Ok(ExecReturnValue {
+				status: STATUS_SUCCESS,
+				data: Vec::new(),
+			})
 		}
 		fn terminate(
 			&mut self,
@@ -360,21 +364,22 @@ mod tests {
 			self.rent_allowance
 		}

-		fn block_number(&self) -> u64 { 121 }
+		fn block_number(&self) -> u64 {
+			121
+		}

-		fn max_value_size(&self) -> u32 { 16_384 }
+		fn max_value_size(&self) -> u32 {
+			16_384
+		}

 		fn get_runtime_storage(&self, key: &[u8]) -> Option<Vec<u8>> {
-			let opt_value = self.runtime_storage_keys
-				.borrow_mut()
-				.remove(key);
-			opt_value.unwrap_or_else(||
+			let opt_value = self.runtime_storage_keys.borrow_mut().remove(key);
+			opt_value.unwrap_or_else(|| {
 				panic!(
 					"{:?} doesn't exist. values that do exist {:?}",
-					key,
-					self.runtime_storage_keys
-				)
+					key, self.runtime_storage_keys
 				)
+			})
 		}
 		fn get_weight_price(&self, weight: Weight) -> BalanceOf<Self::T> {
 			BalanceOf::<Self::T>::from(1312_u32).saturating_mul(weight.into())
@@ -387,9 +392,11 @@ mod tests {
 		fn get_storage(&self, key: &[u8; 32]) -> Option<Vec<u8>> {
 			(**self).get_storage(key)
 		}
-		fn set_storage(&mut self, key: [u8; 32], value: Option<Vec<u8>>)
-			-> Result<(), &'static str>
-		{
+		fn set_storage(
+			&mut self,
+			key: [u8; 32],
+			value: Option<Vec<u8>>,
+		) -> Result<(), &'static str> {
 			(**self).set_storage(key, value)
 		}
 		fn instantiate(
@@ -435,12 +442,7 @@ mod tests {
 			rent_allowance: u64,
 			delta: Vec<StorageKey>,
 		) {
-			(**self).note_restore_to(
-				dest,
-				code_hash,
-				rent_allowance,
-				delta,
-			)
+			(**self).note_restore_to(dest, code_hash, rent_allowance, delta)
 		}
 		fn caller(&self) -> &u64 {
 			(**self).caller()
@@ -499,8 +501,7 @@ mod tests {

 		let wasm = wabt::wat2wasm(wat).unwrap();
 		let schedule = crate::Schedule::default();
-		let prefab_module =
-			prepare_contract::<super::runtime::Env>(&wasm, &schedule).unwrap();
+		let prefab_module = prepare_contract::<super::runtime::Env>(&wasm, &schedule).unwrap();

 		let exec = WasmExecutable {
 			// Use a "call" convention.
@@ -554,7 +555,8 @@ mod tests {
 			vec![],
 			&mut mock_ext,
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

 		assert_eq!(
 			&mock_ext.transfers,
@@ -614,7 +616,8 @@ mod tests {
 			vec![],
 			&mut mock_ext,
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

 		assert_eq!(
 			&mock_ext.transfers,
@@ -676,7 +679,8 @@ mod tests {
 			vec![],
 			&mut mock_ext,
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

 		assert_eq!(
 			&mock_ext.instantiates,
@@ -719,7 +723,8 @@ mod tests {
 			vec![],
 			&mut mock_ext,
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

 		assert_eq!(
 			&mock_ext.terminations,
@@ -777,7 +782,8 @@ mod tests {
 			vec![],
 			&mut mock_ext,
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

 		assert_eq!(
 			&mock_ext.transfers,
@@ -861,18 +867,23 @@ mod tests {
 	#[test]
 	fn get_storage_puts_data_into_scratch_buf() {
 		let mut mock_ext = MockExt::default();
-		mock_ext
-			.storage
-			.insert([0x11; 32], [0x22; 32].to_vec());
+		mock_ext.storage.insert([0x11; 32], [0x22; 32].to_vec());

 		let output = execute(
 			CODE_GET_STORAGE,
 			vec![],
 			mock_ext,
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

-		assert_eq!(output, ExecReturnValue { status: STATUS_SUCCESS, data: [0x22; 32].to_vec() });
+		assert_eq!(
+			output,
+			ExecReturnValue {
+				status: STATUS_SUCCESS,
+				data: [0x22; 32].to_vec()
+			}
+		);
 	}

 	/// calls `ext_caller`, loads the address from the scratch buffer and
@@ -934,7 +945,8 @@ mod tests {
 			vec![],
 			MockExt::default(),
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();
 	}

 	/// calls `ext_address`, loads the address from the scratch buffer and
@@ -996,7 +1008,8 @@ mod tests {
 			vec![],
 			MockExt::default(),
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();
 	}

 	const CODE_BALANCE: &str = r#"
@@ -1051,12 +1064,7 @@ mod tests {
 	#[test]
 	fn balance() {
 		let mut gas_meter = GasMeter::new(GAS_LIMIT);
-		let _ = execute(
-			CODE_BALANCE,
-			vec![],
-			MockExt::default(),
-			&mut gas_meter,
-		).unwrap();
+		let _ = execute(CODE_BALANCE, vec![], MockExt::default(), &mut gas_meter).unwrap();
 	}

 	const CODE_GAS_PRICE: &str = r#"
@@ -1111,12 +1119,7 @@ mod tests {
 	#[test]
 	fn gas_price() {
 		let mut gas_meter = GasMeter::new(GAS_LIMIT);
-		let _ = execute(
-			CODE_GAS_PRICE,
-			vec![],
-			MockExt::default(),
-			&mut gas_meter,
-		).unwrap();
+		let _ = execute(CODE_GAS_PRICE, vec![], MockExt::default(), &mut gas_meter).unwrap();
 	}

 	const CODE_GAS_LEFT: &str = r#"
@@ -1170,16 +1173,14 @@ mod tests {
 	fn gas_left() {
 		let mut gas_meter = GasMeter::new(GAS_LIMIT);

-		let output = execute(
-			CODE_GAS_LEFT,
-			vec![],
-			MockExt::default(),
-			&mut gas_meter,
-		).unwrap();
+		let output = execute(CODE_GAS_LEFT, vec![], MockExt::default(), &mut gas_meter).unwrap();

 		let gas_left = Gas::decode(&mut output.data.as_slice()).unwrap();
 		assert!(gas_left < GAS_LIMIT, "gas_left must be less than initial");
-		assert!(gas_left > gas_meter.gas_left(), "gas_left must be greater than final");
+		assert!(
+			gas_left > gas_meter.gas_left(),
+			"gas_left must be greater than final"
+		);
 	}

 	const CODE_VALUE_TRANSFERRED: &str = r#"
@@ -1239,7 +1240,8 @@ mod tests {
 			vec![],
 			MockExt::default(),
 			&mut gas_meter,
-		).unwrap();
+		)
+		.unwrap();
 	}

 	const CODE_DISPATCH_CALL: &str = r#"
@@ -1270,13 +1272,14 @@ mod tests {
 			vec![],
 			&mut mock_ext,
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

 		assert_eq!(
 			&mock_ext.dispatches,
-			&[DispatchEntry(
-				Call::Balances(pallet_balances::Call::set_balance(42, 1337, 0)),
-			)]
+			&[DispatchEntry(Call::Balances(
+				pallet_balances::Call::set_balance(42, 1337, 0)
+			),)]
 		);
 	}

@@ -1310,9 +1313,16 @@ mod tests {
 			vec![],
 			MockExt::default(),
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

-		assert_eq!(output, ExecReturnValue { status: STATUS_SUCCESS, data: vec![1, 2, 3, 4] });
+		assert_eq!(
+			output,
+			ExecReturnValue {
+				status: STATUS_SUCCESS,
+				data: vec![1, 2, 3, 4]
+			}
+		);
 	}

 	const CODE_TIMESTAMP_NOW: &str = r#"
@@ -1372,7 +1382,8 @@ mod tests {
 			vec![],
 			MockExt::default(),
 			&mut gas_meter,
-		).unwrap();
+		)
+		.unwrap();
 	}

 	const CODE_MINIMUM_BALANCE: &str = r#"
@@ -1431,7 +1442,8 @@ mod tests {
 			vec![],
 			MockExt::default(),
 			&mut gas_meter,
-		).unwrap();
+		)
+		.unwrap();
 	}

 	const CODE_TOMBSTONE_DEPOSIT: &str = r#"
@@ -1490,7 +1502,8 @@ mod tests {
 			vec![],
 			MockExt::default(),
 			&mut gas_meter,
-		).unwrap();
+		)
+		.unwrap();
 	}

 	const CODE_RANDOM: &str = r#"
@@ -1554,19 +1567,15 @@ mod tests {
 	fn random() {
 		let mut gas_meter = GasMeter::new(GAS_LIMIT);

-		let output = execute(
-			CODE_RANDOM,
-			vec![],
-			MockExt::default(),
-			&mut gas_meter,
-		).unwrap();
+		let output = execute(CODE_RANDOM, vec![], MockExt::default(), &mut gas_meter).unwrap();

 		// The mock ext just returns the same data that was passed as the subject.
 		assert_eq!(
 			output,
 			ExecReturnValue {
 				status: STATUS_SUCCESS,
-				data: hex!("000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F").to_vec(),
+				data: hex!("000102030405060708090A0B0C0D0E0F000102030405060708090A0B0C0D0E0F")
+					.to_vec(),
 			},
 		);
 	}
@@ -1598,17 +1607,15 @@ mod tests {
 	fn deposit_event() {
 		let mut mock_ext = MockExt::default();
 		let mut gas_meter = GasMeter::new(GAS_LIMIT);
-		let _ = execute(
-			CODE_DEPOSIT_EVENT,
-			vec![],
-			&mut mock_ext,
-			&mut gas_meter
-		).unwrap();
+		let _ = execute(CODE_DEPOSIT_EVENT, vec![], &mut mock_ext, &mut gas_meter).unwrap();

-		assert_eq!(mock_ext.events, vec![
-			(vec![H256::repeat_byte(0x33)],
-			vec![0x00, 0x01, 0x2a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xe5, 0x14, 0x00])
-		]);
+		assert_eq!(
+			mock_ext.events,
+			vec![(
+				vec![H256::repeat_byte(0x33)],
+				vec![0x00, 0x01, 0x2a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xe5, 0x14, 0x00]
+			)]
+		);

 		assert_eq!(gas_meter.gas_left(), 9967000000);
 	}
@@ -1653,7 +1660,8 @@ mod tests {
 				&mut gas_meter
 			),
 			Err(ExecError {
-				reason: DispatchError::Other("contract trapped during execution"), buffer: _
+				reason: DispatchError::Other("contract trapped during execution"),
+				buffer: _,
 			})
 		);
 	}
@@ -1696,7 +1704,10 @@ mod tests {
 				MockExt::default(),
 				&mut gas_meter
 			),
-			Err(ExecError { reason: DispatchError::Other("contract trapped during execution"), buffer: _ })
+			Err(ExecError {
+				reason: DispatchError::Other("contract trapped during execution"),
+				buffer: _,
+			})
 		);
 	}

@@ -1759,7 +1770,8 @@ mod tests {
 			vec![],
 			MockExt::default(),
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();
 	}

 	// asserts that the size of the input data is 4.
@@ -1799,7 +1811,8 @@ mod tests {
 			input_data,
 			MockExt::default(),
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

 		assert_eq!(output.data.len(), 0);
 		assert_eq!(output.data.capacity(), 1_234);
@@ -1815,7 +1828,9 @@ mod tests {
 			input_data,
 			MockExt::default(),
 			&mut GasMeter::new(GAS_LIMIT),
-		).err().unwrap();
+		)
+		.err()
+		.unwrap();

 		assert_eq!(error.buffer.capacity(), 1_234);
 	}
@@ -1869,9 +1884,16 @@ mod tests {
 			hex!("00112233445566778899").to_vec(),
 			MockExt::default(),
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

-		assert_eq!(output, ExecReturnValue { status: 0, data: hex!("445566778899").to_vec() });
+		assert_eq!(
+			output,
+			ExecReturnValue {
+				status: 0,
+				data: hex!("445566778899").to_vec()
+			}
+		);
 		assert!(output.is_success());
 	}

@@ -1882,9 +1904,16 @@ mod tests {
 			hex!("112233445566778899").to_vec(),
 			MockExt::default(),
 			&mut GasMeter::new(GAS_LIMIT),
-		).unwrap();
+		)
+		.unwrap();

-		assert_eq!(output, ExecReturnValue { status: 17, data: hex!("5566778899").to_vec() });
+		assert_eq!(
+			output,
+			ExecReturnValue {
+				status: 17,
+				data: hex!("5566778899").to_vec()
+			}
+		);
 		assert!(!output.is_success());
 	}

@@ -1973,17 +2002,15 @@ mod tests {
 		// "\01\02\03\04" - Some(0x14144020)
 		// "\02\03\04\05" - None
 		*mock_ext.runtime_storage_keys.borrow_mut() = [
-			([1, 2, 3, 4].to_vec(), Some(0x14144020u32.to_le_bytes().to_vec())),
+			(
+				[1, 2, 3, 4].to_vec(),
+				Some(0x14144020u32.to_le_bytes().to_vec()),
+			),
 			([2, 3, 4, 5].to_vec().to_vec(), None),
 		]
 		.iter()
 		.cloned()
 		.collect();
-		let _ = execute(
-			CODE_GET_RUNTIME_STORAGE,
-			vec![],
-			mock_ext,
-			&mut gas_meter,
-		).unwrap();
+		let _ = execute(CODE_GET_RUNTIME_STORAGE, vec![], mock_ext, &mut gas_meter).unwrap();
 	}
 }
@@ -18,15 +18,15 @@
 //! wasm module before execution. It also extracts some essential information
 //! from a module.

-use crate::wasm::env_def::ImportSatisfyCheck;
-use crate::wasm::PrefabWasmModule;
-use crate::Schedule;
+use crate::{
+	wasm::{env_def::ImportSatisfyCheck, PrefabWasmModule},
+	Schedule,
+};

-use parity_wasm::elements::{self, Internal, External, MemoryType, Type, ValueType};
-use pwasm_utils;
-use pwasm_utils::rules;
+use parity_wasm::elements::{self, External, Internal, MemoryType, Type, ValueType};
+use pwasm_utils::{self, rules};
+use sp_runtime::traits::SaturatedConversion;
 use sp_std::prelude::*;
-use sp_runtime::traits::{SaturatedConversion};

 struct ContractModule<'a> {
 	/// A deserialized module. The module is valid (this is Guaranteed by `new` method).
@@ -39,10 +39,7 @@ impl<'a> ContractModule<'a> {
 	///
 	/// Returns `Err` if the `original_code` couldn't be decoded or
 	/// if it contains an invalid module.
-	fn new(
-		original_code: &[u8],
-		schedule: &'a Schedule,
-	) -> Result<Self, &'static str> {
+	fn new(original_code: &[u8], schedule: &'a Schedule) -> Result<Self, &'static str> {
 		use wasmi_validation::{validate_module, PlainValidator};

 		let module =
@@ -53,10 +50,7 @@ impl<'a> ContractModule<'a> {

 		// Return a `ContractModule` instance with
 		// __valid__ module.
-		Ok(ContractModule {
-			module,
-			schedule,
-		})
+		Ok(ContractModule { module, schedule })
 	}

 	/// Ensures that module doesn't declare internal memories.
@@ -65,7 +59,8 @@ impl<'a> ContractModule<'a> {
 	/// Memory section contains declarations of internal linear memories, so if we find one
 	/// we reject such a module.
 	fn ensure_no_internal_memory(&self) -> Result<(), &'static str> {
-		if self.module
+		if self
+			.module
 			.memory_section()
 			.map_or(false, |ms| ms.entries().len() > 0)
 		{
@@ -86,7 +81,7 @@ impl<'a> ContractModule<'a> {
 				// Check the table's initial size as there is no instruction or environment function
 				// capable of growing the table.
 				if table_type.limits().initial() > limit {
-					return Err("table exceeds maximum size allowed")
+					return Err("table exceeds maximum size allowed");
 				}
 			}
 		}
@@ -98,8 +93,9 @@ impl<'a> ContractModule<'a> {
 		if let Some(global_section) = self.module.global_section() {
 			for global in global_section.entries() {
 				match global.global_type().content_type() {
-					ValueType::F32 | ValueType::F64 =>
-						return Err("use of floating point type in globals is forbidden"),
+					ValueType::F32 | ValueType::F64 => {
+						return Err("use of floating point type in globals is forbidden")
+					}
 					_ => {}
 				}
 			}
@@ -109,8 +105,9 @@ impl<'a> ContractModule<'a> {
 			for func_body in code_section.bodies() {
 				for local in func_body.locals() {
 					match local.value_type() {
-						ValueType::F32 | ValueType::F64 =>
-							return Err("use of floating point type in locals is forbidden"),
+						ValueType::F32 | ValueType::F64 => {
+							return Err("use of floating point type in locals is forbidden")
+						}
 						_ => {}
 					}
 				}
@@ -124,8 +121,11 @@ impl<'a> ContractModule<'a> {
 						let return_type = func_type.return_type();
 						for value_type in func_type.params().iter().chain(return_type.iter()) {
 							match value_type {
-								ValueType::F32 | ValueType::F64 =>
-									return Err("use of floating point type in function types is forbidden"),
+								ValueType::F32 | ValueType::F64 => {
+									return Err(
+										"use of floating point type in function types is forbidden",
+									)
+								}
 								_ => {}
 							}
 						}
@@ -138,8 +138,7 @@ impl<'a> ContractModule<'a> {
 	}

 	fn inject_gas_metering(self) -> Result<Self, &'static str> {
-		let gas_rules =
-			rules::Set::new(
+		let gas_rules = rules::Set::new(
 			self.schedule.regular_op_cost.clone().saturated_into(),
 			Default::default(),
 		)
@@ -195,11 +194,9 @@ impl<'a> ContractModule<'a> {
 			.map(|is| is.entries())
 			.unwrap_or(&[])
 			.iter()
-			.filter(|entry| {
-				match *entry.external() {
+			.filter(|entry| match *entry.external() {
 				External::Function(_) => true,
 				_ => false,
-				}
 			})
 			.count();

@@ -232,15 +229,17 @@ impl<'a> ContractModule<'a> {
 			// The [] -> [] signature predates the [] -> [i32] signature and is supported for
 			// backwards compatibility. This will likely be removed once ink! is updated to
 			// generate modules with the new function signatures.
-			let func_ty_idx = func_entries.get(fn_idx as usize)
+			let func_ty_idx = func_entries
+				.get(fn_idx as usize)
 				.ok_or_else(|| "export refers to non-existent function")?
 				.type_ref();
 			let Type::Function(ref func_ty) = types
 				.get(func_ty_idx as usize)
 				.ok_or_else(|| "function has a non-existent type")?;
-			if !func_ty.params().is_empty() ||
-				!(func_ty.return_type().is_none() ||
-					func_ty.return_type() == Some(ValueType::I32)) {
+			if !func_ty.params().is_empty()
+				|| !(func_ty.return_type().is_none()
+					|| func_ty.return_type() == Some(ValueType::I32))
+			{
 				return Err("entry point has wrong signature");
 			}
 		}
@@ -286,10 +285,10 @@ impl<'a> ContractModule<'a> {
 				&External::Function(ref type_idx) => type_idx,
 				&External::Memory(ref memory_type) => {
 					if import.field() != "memory" {
-						return Err("Memory import must have the field name 'memory'")
+						return Err("Memory import must have the field name 'memory'");
 					}
 					if imported_mem_type.is_some() {
-						return Err("Multiple memory imports defined")
+						return Err("Multiple memory imports defined");
 					}
 					imported_mem_type = Some(memory_type);
 					continue;
@@ -317,8 +316,7 @@ impl<'a> ContractModule<'a> {
 	}

 	fn into_wasm_code(self) -> Result<Vec<u8>, &'static str> {
-		elements::serialize(self.module)
-			.map_err(|_| "error serializing instrumented module")
+		elements::serialize(self.module).map_err(|_| "error serializing instrumented module")
 	}
 }

@@ -394,9 +392,9 @@ pub fn prepare_contract<C: ImportSatisfyCheck>(
 mod tests {
 	use super::*;
 	use crate::exec::Ext;
+	use assert_matches::assert_matches;
 	use std::fmt;
 	use wabt;
-	use assert_matches::assert_matches;

 	impl fmt::Debug for PrefabWasmModule {
 		fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
@@ -429,7 +427,8 @@ mod tests {
 		};
 	}

-	prepare_test!(no_floats,
+	prepare_test!(
+		no_floats,
 		r#"
 		(module
 			(func (export "call")
@@ -454,7 +453,8 @@ mod tests {
 			assert_eq!(Schedule::default().max_memory_pages, 16);
 		}

-		prepare_test!(memory_with_one_page,
+		prepare_test!(
+			memory_with_one_page,
 			r#"
 			(module
 				(import "env" "memory" (memory 1 1))
@@ -466,7 +466,8 @@ mod tests {
 			Ok(_)
 		);

-		prepare_test!(internal_memory_declaration,
+		prepare_test!(
+			internal_memory_declaration,
 			r#"
 			(module
 				(memory 1 1)
@@ -478,7 +479,8 @@ mod tests {
 			Err("module declares internal memory")
 		);

-		prepare_test!(no_memory_import,
+		prepare_test!(
+			no_memory_import,
 			r#"
 			(module
 				;; no memory imported
@@ -489,7 +491,8 @@ mod tests {
 			Ok(_)
 		);

-		prepare_test!(initial_exceeds_maximum,
+		prepare_test!(
+			initial_exceeds_maximum,
 			r#"
 			(module
 				(import "env" "memory" (memory 16 1))
@@ -501,7 +504,8 @@ mod tests {
 			Err("Module is not valid")
 		);

-		prepare_test!(no_maximum,
+		prepare_test!(
+			no_maximum,
 			r#"
 			(module
 				(import "env" "memory" (memory 1))
@@ -513,7 +517,8 @@ mod tests {
 			Err("Maximum number of pages should be always declared.")
 		);

-		prepare_test!(requested_maximum_exceeds_configured_maximum,
+		prepare_test!(
+			requested_maximum_exceeds_configured_maximum,
 			r#"
 			(module
 				(import "env" "memory" (memory 1 17))
@@ -525,7 +530,8 @@ mod tests {
 			Err("Maximum number of pages should not exceed the configured maximum.")
 		);

-		prepare_test!(field_name_not_memory,
+		prepare_test!(
+			field_name_not_memory,
 			r#"
 			(module
 				(import "env" "forgetit" (memory 1 1))
@@ -537,7 +543,8 @@ mod tests {
 			Err("Memory import must have the field name 'memory'")
 		);

-		prepare_test!(multiple_memory_imports,
+		prepare_test!(
+			multiple_memory_imports,
 			r#"
 			(module
 				(import "env" "memory" (memory 1 1))
@@ -550,7 +557,8 @@ mod tests {
 			Err("Module is not valid")
 		);

-		prepare_test!(table_import,
+		prepare_test!(
+			table_import,
 			r#"
 			(module
 				(import "env" "table" (table 1 anyfunc))
@@ -562,7 +570,8 @@ mod tests {
 			Err("Cannot import tables")
 		);

-		prepare_test!(global_import,
+		prepare_test!(
+			global_import,
 			r#"
 			(module
 				(global $g (import "env" "global") i32)
@@ -583,7 +592,8 @@ mod tests {
 			assert_eq!(Schedule::default().max_table_size, 16384);
 		}

-		prepare_test!(no_tables,
+		prepare_test!(
+			no_tables,
 			r#"
 			(module
 				(func (export "call"))
@@ -593,7 +603,8 @@ mod tests {
 			Ok(_)
 		);

-		prepare_test!(table_valid_size,
+		prepare_test!(
+			table_valid_size,
 			r#"
 			(module
 				(table 10000 funcref)
@@ -605,7 +616,8 @@ mod tests {
 			Ok(_)
 		);

-		prepare_test!(table_too_big,
+		prepare_test!(
+			table_too_big,
 			r#"
 			(module
 				(table 20000 funcref)
@@ -620,7 +632,8 @@ mod tests {
 	mod imports {
 		use super::*;

-		prepare_test!(can_import_legit_function,
+		prepare_test!(
+			can_import_legit_function,
 			r#"
 			(module
 				(import "env" "nop" (func (param i64)))
@@ -634,7 +647,8 @@ mod tests {

 		// even though gas is defined the contract can't import it since
 		// it is an implementation defined.
-		prepare_test!(can_not_import_gas_function,
+		prepare_test!(
+			can_not_import_gas_function,
 			r#"
 			(module
 				(import "env" "gas" (func (param i32)))
@@ -647,7 +661,8 @@ mod tests {
 		);

 		// nothing can be imported from non-"env" module for now.
-		prepare_test!(non_env_import,
+		prepare_test!(
+			non_env_import,
 			r#"
 			(module
 				(import "another_module" "memory" (memory 1 1))
@@ -660,7 +675,8 @@ mod tests {
 		);

 		// wrong signature
-		prepare_test!(wrong_signature,
+		prepare_test!(
+			wrong_signature,
 			r#"
 			(module
 				(import "env" "gas" (func (param i64)))
@@ -672,7 +688,8 @@ mod tests {
 			Err("module imports a non-existent function")
 		);

-		prepare_test!(unknown_func_name,
+		prepare_test!(
+			unknown_func_name,
 			r#"
 			(module
 				(import "env" "unknown_func" (func))
@@ -684,7 +701,8 @@ mod tests {
 			Err("module imports a non-existent function")
 		);

-		prepare_test!(ext_println_debug_disabled,
+		prepare_test!(
+			ext_println_debug_disabled,
 			r#"
 			(module
 				(import "env" "ext_println" (func $ext_println (param i32 i32)))
@@ -698,7 +716,9 @@ mod tests {

 		#[test]
 		fn ext_println_debug_enabled() {
-			let wasm = wabt::Wat2Wasm::new().validate(false).convert(
+			let wasm = wabt::Wat2Wasm::new()
+				.validate(false)
+				.convert(
 					r#"
 				(module
 					(import "env" "ext_println" (func $ext_println (param i32 i32)))
@@ -706,8 +726,9 @@ mod tests {
 					(func (export "call"))
 					(func (export "deploy"))
 				)
-				"#
-			).unwrap();
+				"#,
+				)
+				.unwrap();
 			let mut schedule = Schedule::default();
 			schedule.enable_println = true;
 			let r = prepare_contract::<TestEnv>(wasm.as_ref(), &schedule);
@@ -718,7 +739,8 @@ mod tests {
 	mod entrypoints {
 		use super::*;

-		prepare_test!(it_works,
+		prepare_test!(
+			it_works,
 			r#"
 			(module
 				(func (export "call"))
@@ -728,7 +750,8 @@ mod tests {
 			Ok(_)
 		);

-		prepare_test!(omit_deploy,
+		prepare_test!(
+			omit_deploy,
 			r#"
 			(module
 				(func (export "call"))
@@ -737,7 +760,8 @@ mod tests {
 			Err("deploy function isn't exported")
 		);

-		prepare_test!(omit_call,
+		prepare_test!(
+			omit_call,
 			r#"
 			(module
 				(func (export "deploy"))
@@ -747,7 +771,8 @@ mod tests {
 		);

 		// Try to use imported function as an entry point.
-		prepare_test!(try_sneak_export_as_entrypoint,
+		prepare_test!(
+			try_sneak_export_as_entrypoint,
 			r#"
 			(module
 				(import "env" "panic" (func))
@@ -761,7 +786,8 @@ mod tests {
 		);

 		// Try to use imported function as an entry point.
-		prepare_test!(try_sneak_export_as_global,
+		prepare_test!(
+			try_sneak_export_as_global,
 			r#"
 			(module
 				(func (export "deploy"))
@@ -771,7 +797,8 @@ mod tests {
 			Err("expected a function")
 		);

-		prepare_test!(wrong_signature,
+		prepare_test!(
+			wrong_signature,
 			r#"
 			(module
 				(func (export "deploy"))
@@ -781,7 +808,8 @@ mod tests {
 			Err("entry point has wrong signature")
 		);

-		prepare_test!(unknown_exports,
+		prepare_test!(
+			unknown_exports,
 			r#"
 			(module
 				(func (export "call"))
@@ -792,7 +820,8 @@ mod tests {
 			Err("unknown export: expecting only deploy and call functions")
 		);

-		prepare_test!(global_float,
+		prepare_test!(
+			global_float,
 			r#"
 			(module
 				(global $x f32 (f32.const 0))
@@ -803,7 +832,8 @@ mod tests {
 			Err("use of floating point type in globals is forbidden")
 		);

-		prepare_test!(local_float,
+		prepare_test!(
+			local_float,
 			r#"
 			(module
 				(func $foo (local f32))
@@ -814,7 +844,8 @@ mod tests {
 			Err("use of floating point type in locals is forbidden")
 		);

-		prepare_test!(param_float,
+		prepare_test!(
+			param_float,
 			r#"
 			(module
 				(func $foo (param f32))
@@ -825,7 +856,8 @@ mod tests {
 			Err("use of floating point type in function types is forbidden")
 		);

-		prepare_test!(result_float,
+		prepare_test!(
+			result_float,
 			r#"
 			(module
 				(func $foo (result f32) (f32.const 0))
@@ -16,23 +16,18 @@

 //! Environment definition of the wasm smart-contract runtime.

-use crate::{Schedule, Trait, CodeHash, BalanceOf};
-use crate::exec::{
-	Ext, ExecResult, ExecError, ExecReturnValue, StorageKey, TopicOf, STATUS_SUCCESS,
+use crate::{
+	exec::{ExecError, ExecResult, ExecReturnValue, Ext, StorageKey, TopicOf, STATUS_SUCCESS},
+	gas::{Gas, GasMeter, GasMeterResult, Token},
+	BalanceOf, CodeHash, Schedule, Trait,
 };
-use crate::gas::{Gas, GasMeter, Token, GasMeterResult};
-use sp_sandbox;
-use frame_system;
-use sp_std::{prelude::*, mem, convert::TryInto};
 use codec::{Decode, Encode};
-use sp_runtime::traits::{Bounded, SaturatedConversion};
-use sp_io::hashing::{
-	keccak_256,
-	blake2_256,
-	blake2_128,
-	sha2_256,
-};
 use frame_support::weights::GetDispatchInfo;
+use frame_system;
+use sp_io::hashing::{blake2_128, blake2_256, keccak_256, sha2_256};
+use sp_runtime::traits::{Bounded, SaturatedConversion};
+use sp_sandbox;
+use sp_std::{convert::TryInto, mem, prelude::*};

 /// The value returned from ext_call and ext_instantiate contract external functions if the call or
 /// instantiation traps. This value is chosen as if the execution does not trap, the return value
@@ -93,19 +88,19 @@ pub(crate) fn to_execution_result<E: Ext>(
 				status: STATUS_SUCCESS,
 				data,
 			})
-		},
+		}
 		Some(SpecialTrap::Termination) => {
 			return Ok(ExecReturnValue {
 				status: STATUS_SUCCESS,
 				data: Vec::new(),
 			})
-		},
+		}
 		Some(SpecialTrap::OutOfGas) => {
 			return Err(ExecError {
 				reason: "ran out of gas during contract execution".into(),
 				buffer: runtime.scratch_buf,
 			})
-		},
+		}
 		None => (),
 	}

@@ -115,29 +110,43 @@ pub(crate) fn to_execution_result<E: Ext>(
 		Ok(sp_sandbox::ReturnValue::Unit) => {
 			let mut buffer = runtime.scratch_buf;
 			buffer.clear();
-			Ok(ExecReturnValue { status: STATUS_SUCCESS, data: buffer })
+			Ok(ExecReturnValue {
+				status: STATUS_SUCCESS,
+				data: buffer,
+			})
 		}
 		Ok(sp_sandbox::ReturnValue::Value(sp_sandbox::Value::I32(exit_code))) => {
-			let status = (exit_code & 0xFF).try_into()
+			let status = (exit_code & 0xFF)
+				.try_into()
 				.expect("exit_code is masked into the range of a u8; qed");
-			Ok(ExecReturnValue { status, data: runtime.scratch_buf })
+			Ok(ExecReturnValue {
+				status,
+				data: runtime.scratch_buf,
+			})
 		}
 		// This should never happen as the return type of exported functions should have been
 		// validated by the code preparation process. However, because panics are really
 		// undesirable in the runtime code, we treat this as a trap for now. Eventually, we might
 		// want to revisit this.
-		Ok(_) => Err(ExecError { reason: "return type error".into(), buffer: runtime.scratch_buf }),
+		Ok(_) => Err(ExecError {
+			reason: "return type error".into(),
+			buffer: runtime.scratch_buf,
+		}),
 		// `Error::Module` is returned only if instantiation or linking failed (i.e.
 		// wasm binary tried to import a function that is not provided by the host).
 		// This shouldn't happen because validation process ought to reject such binaries.
 		//
 		// Because panics are really undesirable in the runtime code, we treat this as
 		// a trap for now. Eventually, we might want to revisit this.
-		Err(sp_sandbox::Error::Module) =>
-			Err(ExecError { reason: "validation error".into(), buffer: runtime.scratch_buf }),
+		Err(sp_sandbox::Error::Module) => Err(ExecError {
+			reason: "validation error".into(),
+			buffer: runtime.scratch_buf,
+		}),
 		// Any other kind of a trap should result in a failure.
-		Err(sp_sandbox::Error::Execution) | Err(sp_sandbox::Error::OutOfBounds) =>
-			Err(ExecError { reason: "contract trapped during execution".into(), buffer: runtime.scratch_buf }),
+		Err(sp_sandbox::Error::Execution) | Err(sp_sandbox::Error::OutOfBounds) => Err(ExecError {
+			reason: "contract trapped during execution".into(),
+			buffer: runtime.scratch_buf,
+		}),
 	}
 }

@@ -188,14 +197,12 @@ impl<T: Trait> Token<T> for RuntimeToken {

 				data_cost
 					.and_then(|data_cost| {
-						topics_cost.and_then(|topics_cost| {
-							data_cost.checked_add(topics_cost)
+						topics_cost.and_then(|topics_cost| data_cost.checked_add(topics_cost))
 					})
-					})
-					.and_then(|data_and_topics_cost|
+					.and_then(|data_and_topics_cost| {
 						data_and_topics_cost.checked_add(metadata.event_base_cost)
-					)
-			},
+					})
+			}
 			DispatchWithWeight(gas) => gas.checked_add(metadata.dispatch_base_cost),
 		};

@@ -217,7 +224,7 @@ fn charge_gas<T: Trait, Tok: Token<T>>(
 		GasMeterResult::OutOfGas => {
 			*special_trap = Some(SpecialTrap::OutOfGas);
 			Err(sp_sandbox::HostError)
-		},
+		}
 	}
 }

@@ -242,7 +249,9 @@ fn read_sandbox_memory<E: Ext>(
 	)?;

 	let mut buf = vec![0u8; len as usize];
-	ctx.memory.get(ptr, buf.as_mut_slice()).map_err(|_| sp_sandbox::HostError)?;
+	ctx.memory
+		.get(ptr, buf.as_mut_slice())
+		.map_err(|_| sp_sandbox::HostError)?;
 	Ok(buf)
 }

@@ -267,7 +276,9 @@ fn read_sandbox_memory_into_scratch<E: Ext>(
 	)?;

 	ctx.scratch_buf.resize(len as usize, 0);
-	ctx.memory.get(ptr, ctx.scratch_buf.as_mut_slice()).map_err(|_| sp_sandbox::HostError)?;
+	ctx.memory
+		.get(ptr, ctx.scratch_buf.as_mut_slice())
+		.map_err(|_| sp_sandbox::HostError)?;
 	Ok(())
 }

@@ -1165,14 +1176,10 @@ where
 /// the order of items is not preserved.
 fn has_duplicates<T: PartialEq + AsRef<[u8]>>(items: &mut Vec<T>) -> bool {
 	// Sort the vector
-	items.sort_unstable_by(|a, b| {
-		Ord::cmp(a.as_ref(), b.as_ref())
-	});
+	items.sort_unstable_by(|a, b| Ord::cmp(a.as_ref(), b.as_ref()));
 	// And then find any two consecutive equal elements.
-	items.windows(2).any(|w| {
-		match w {
+	items.windows(2).any(|w| match w {
 		&[ref a, ref b] => a == b,
 		_ => false,
-		}
 	})
 }
@@ -17,7 +17,8 @@
 #![cfg_attr(not(feature = "std"), no_std)]

 use frame_support::{
-	decl_event, decl_module, dispatch::DispatchResult,
+	decl_event, decl_module,
+	dispatch::DispatchResult,
 	traits::{Currency, ExistenceRequirement, WithdrawReason},
 };
 use frame_system::ensure_signed;
@@ -0,0 +1,17 @@
+[package]
+name = "rococo-parachain-primitives"
+version = "0.1.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+
+[dependencies]
+# Substrate dependencies
+sp-runtime = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "rococo-branch" }
+sp-core = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "rococo-branch" }
+
+[features]
+default = [ "std" ]
+std = [
+	"sp-runtime/std",
+	"sp-core/std"
+]
@@ -0,0 +1,59 @@
+// Copyright 2020 Parity Technologies (UK) Ltd.
+// This file is part of Cumulus.
+
+// 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 Cumulus.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Primitives used by the Parachains Tick, Trick and Track.
+
+#![cfg_attr(not(feature = "std"), no_std)]
+
+use sp_runtime::{
+	generic,
+	traits::{BlakeTwo256, IdentifyAccount, Verify},
+	MultiSignature,
+};
+
+pub use sp_runtime::OpaqueExtrinsic as UncheckedExtrinsic;
+
+/// Opaque block header type.
+pub type Header = generic::Header<BlockNumber, BlakeTwo256>;
+/// Opaque block type.
+pub type Block = generic::Block<Header, UncheckedExtrinsic>;
+/// Opaque block identifier type.
+pub type BlockId = generic::BlockId<Block>;
+/// An index to a block.
+pub type BlockNumber = u32;
+
+/// Alias to 512-bit hash when used in the context of a transaction signature on the chain.
+pub type Signature = MultiSignature;
+
+/// Some way of identifying an account on the chain. We intentionally make it equivalent
+/// to the public key of our transaction signing scheme.
+pub type AccountId = <<Signature as Verify>::Signer as IdentifyAccount>::AccountId;
+
+/// The type for looking up accounts. We don't expect more than 4 billion of them, but you
+/// never know...
+pub type AccountIndex = u32;
+
+/// Balance of an account.
+pub type Balance = u128;
+
+/// Index of a transaction in the chain.
+pub type Index = u32;
+
+/// A hash of some data used by the chain.
+pub type Hash = sp_core::H256;
+
+/// Digest item type.
+pub type DigestItem = generic::DigestItem<Hash>;
@@ -10,6 +10,7 @@ codec = { package = "parity-scale-codec", version = "1.3.0", default-features =

 cumulus-token-dealer = { path = "../pallets/token-dealer", default-features = false }
 parachain-info = { path = "../pallets/parachain-info", default-features = false }
+rococo-parachain-primitives = { path = "../primitives", default-features = false }

 # Substrate dependencies
 sp-std = { git = "https://github.com/paritytech/substrate", default-features = false, branch = "rococo-branch" }
@@ -71,6 +72,7 @@ std = [
 	"pallet-sudo/std",
 	"pallet-transaction-payment/std",
 	"parachain-info/std",
+	"rococo-parachain-primitives/std",
 	"cumulus-runtime/std",
 	"cumulus-parachain-upgrade/std",
 	"cumulus-message-broker/std",
@@ -22,13 +22,14 @@
 #[cfg(feature = "std")]
 include!(concat!(env!("OUT_DIR"), "/wasm_binary.rs"));

+use rococo_parachain_primitives::*;
 use sp_api::impl_runtime_apis;
 use sp_core::OpaqueMetadata;
 use sp_runtime::{
 	create_runtime_str, generic, impl_opaque_keys,
-	traits::{BlakeTwo256, Block as BlockT, IdentifyAccount, IdentityLookup, Saturating, Verify},
+	traits::{BlakeTwo256, Block as BlockT, IdentityLookup, Saturating},
 	transaction_validity::{TransactionSource, TransactionValidity},
-	ApplyExtrinsicResult, MultiSignature,
+	ApplyExtrinsicResult,
 };
 use sp_std::prelude::*;
 #[cfg(feature = "std")]
@@ -51,61 +52,18 @@ pub use pallet_timestamp::Call as TimestampCall;
 pub use sp_runtime::BuildStorage;
 pub use sp_runtime::{Perbill, Permill};

-/// An index to a block.
-pub type BlockNumber = u32;
-
-/// Alias to 512-bit hash when used in the context of a transaction signature on the chain.
-pub type Signature = MultiSignature;
-
-/// Some way of identifying an account on the chain. We intentionally make it equivalent
-/// to the public key of our transaction signing scheme.
-pub type AccountId = <<Signature as Verify>::Signer as IdentifyAccount>::AccountId;
-
-/// The type for looking up accounts. We don't expect more than 4 billion of them, but you
-/// never know...
-pub type AccountIndex = u32;
-
-/// Balance of an account.
-pub type Balance = u128;
-
-/// Index of a transaction in the chain.
-pub type Index = u32;
-
-/// A hash of some data used by the chain.
-pub type Hash = sp_core::H256;
-
-/// Digest item type.
-pub type DigestItem = generic::DigestItem<Hash>;
-
-/// 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
-/// of data like extrinsics, allowing for them to continue syncing the network through upgrades
-/// to even the core datastructures.
-pub mod opaque {
-	use super::*;
-
-	pub use sp_runtime::OpaqueExtrinsic as UncheckedExtrinsic;
-
-	/// Opaque block header type.
-	pub type Header = generic::Header<BlockNumber, BlakeTwo256>;
-	/// Opaque block type.
-	pub type Block = generic::Block<Header, UncheckedExtrinsic>;
-	/// Opaque block identifier type.
-	pub type BlockId = generic::BlockId<Block>;
-
 pub type SessionHandlers = ();

 impl_opaque_keys! {
 	pub struct SessionKeys {}
 }
-}

 /// This runtime version.
 pub const VERSION: RuntimeVersion = RuntimeVersion {
 	spec_name: create_runtime_str!("cumulus-test-parachain"),
 	impl_name: create_runtime_str!("cumulus-test-parachain"),
 	authoring_version: 1,
-	spec_version: 1,
+	spec_version: 2,
 	impl_version: 1,
 	apis: RUNTIME_API_VERSIONS,
 	transaction_version: 1,
@@ -266,8 +224,8 @@ impl parachain_info::Trait for Runtime {}
 construct_runtime! {
 	pub enum Runtime where
 		Block = Block,
-		NodeBlock = opaque::Block,
-		UncheckedExtrinsic = UncheckedExtrinsic
+		NodeBlock = rococo_parachain_primitives::Block,
+		UncheckedExtrinsic = UncheckedExtrinsic,
 	{
 		System: frame_system::{Module, Call, Storage, Config, Event<T>},
 		Timestamp: pallet_timestamp::{Module, Call, Storage, Inherent},
@@ -378,11 +336,11 @@ impl_runtime_apis! {
 		fn decode_session_keys(
 			encoded: Vec<u8>,
 		) -> Option<Vec<(Vec<u8>, sp_core::crypto::KeyTypeId)>> {
-			opaque::SessionKeys::decode_into_raw_public_keys(&encoded)
+			SessionKeys::decode_into_raw_public_keys(&encoded)
 		}

 		fn generate_session_keys(seed: Option<Vec<u8>>) -> Vec<u8> {
-			opaque::SessionKeys::generate(seed)
+			SessionKeys::generate(seed)
 		}
 	}
 }
@@ -15,19 +15,20 @@
 // along with Cumulus.  If not, see <http://www.gnu.org/licenses/>.

 use cumulus_primitives::ParaId;
-use parachain_runtime::{
-	AccountId, BalancesConfig, GenesisConfig, Signature, SudoConfig, SystemConfig,
-	ParachainInfoConfig, WASM_BINARY,
-};
+use hex_literal::hex;
+use rococo_parachain_primitives::{AccountId, Signature};
 use sc_chain_spec::{ChainSpecExtension, ChainSpecGroup};
 use sc_service::ChainType;
 use serde::{Deserialize, Serialize};
 use sp_core::{sr25519, Pair, Public};
 use sp_runtime::traits::{IdentifyAccount, Verify};
-use hex_literal::hex;

-/// Specialized `ChainSpec`. This is a specialization of the general Substrate ChainSpec type.
-pub type ChainSpec = sc_service::GenericChainSpec<GenesisConfig, Extensions>;
+/// Specialized `ChainSpec` for the normal parachain runtime.
+pub type ChainSpec = sc_service::GenericChainSpec<parachain_runtime::GenesisConfig, Extensions>;
+
+/// Specialized `ChainSpec` for the contracts parachain runtime.
+pub type ContractsChainSpec =
+	sc_service::GenericChainSpec<parachain_contracts_runtime::GenesisConfig, Extensions>;

 /// Helper function to generate a crypto pair from seed
 pub fn get_from_seed<TPublic: Public>(seed: &str) -> <TPublic::Pair as Pair>::Public {
@@ -99,6 +100,42 @@ pub fn get_chain_spec(id: ParaId) -> ChainSpec {
 	)
 }

+pub fn get_contracts_chain_spec(id: ParaId) -> ContractsChainSpec {
+	ContractsChainSpec::from_genesis(
+		"Contracts Local Testnet",
+		"contracts_local_testnet",
+		ChainType::Local,
+		move || {
+			contracts_testnet_genesis(
+				get_account_id_from_seed::<sr25519::Public>("Alice"),
+				vec![
+					get_account_id_from_seed::<sr25519::Public>("Alice"),
+					get_account_id_from_seed::<sr25519::Public>("Bob"),
+					get_account_id_from_seed::<sr25519::Public>("Charlie"),
+					get_account_id_from_seed::<sr25519::Public>("Dave"),
+					get_account_id_from_seed::<sr25519::Public>("Eve"),
+					get_account_id_from_seed::<sr25519::Public>("Ferdie"),
+					get_account_id_from_seed::<sr25519::Public>("Alice//stash"),
+					get_account_id_from_seed::<sr25519::Public>("Bob//stash"),
+					get_account_id_from_seed::<sr25519::Public>("Charlie//stash"),
+					get_account_id_from_seed::<sr25519::Public>("Dave//stash"),
+					get_account_id_from_seed::<sr25519::Public>("Eve//stash"),
+					get_account_id_from_seed::<sr25519::Public>("Ferdie//stash"),
+				],
+				id,
+			)
+		},
+		vec![],
+		None,
+		None,
+		None,
+		Extensions {
+			relay_chain: "westend-dev".into(),
+			para_id: id.into(),
+		},
+	)
+}
+
 pub fn staging_test_net(id: ParaId) -> ChainSpec {
 	ChainSpec::from_genesis(
 		"Staging Testnet",
@@ -107,7 +144,9 @@ pub fn staging_test_net(id: ParaId) -> ChainSpec {
 		move || {
 			testnet_genesis(
 				hex!["9ed7705e3c7da027ba0583a22a3212042f7e715d3c168ba14f1424e2bc111d00"].into(),
-				vec![hex!["9ed7705e3c7da027ba0583a22a3212042f7e715d3c168ba14f1424e2bc111d00"].into()],
+				vec![
+					hex!["9ed7705e3c7da027ba0583a22a3212042f7e715d3c168ba14f1424e2bc111d00"].into(),
+				],
 				id,
 			)
 		},
@@ -126,22 +165,47 @@ fn testnet_genesis(
 	root_key: AccountId,
 	endowed_accounts: Vec<AccountId>,
 	id: ParaId,
-) -> GenesisConfig {
-	GenesisConfig {
-		frame_system: Some(SystemConfig {
-			code: WASM_BINARY.expect("WASM binary was not build, please build it!").to_vec(),
+) -> parachain_runtime::GenesisConfig {
+	parachain_runtime::GenesisConfig {
+		frame_system: Some(parachain_runtime::SystemConfig {
+			code: parachain_runtime::WASM_BINARY
+				.expect("WASM binary was not build, please build it!")
+				.to_vec(),
 			changes_trie_config: Default::default(),
 		}),
-		pallet_balances: Some(BalancesConfig {
+		pallet_balances: Some(parachain_runtime::BalancesConfig {
 			balances: endowed_accounts
 				.iter()
 				.cloned()
 				.map(|k| (k, 1 << 60))
 				.collect(),
 		}),
-		pallet_sudo: Some(SudoConfig { key: root_key }),
-		parachain_info: Some(ParachainInfoConfig { parachain_id: id }),
-		// TODO: add contracts genesis for the contracts runtime
-		// pallet_contracts: Some(parachain_runtime::ContractsConfig { current_schedule: Default::default() }),
+		pallet_sudo: Some(parachain_runtime::SudoConfig { key: root_key }),
+		parachain_info: Some(parachain_runtime::ParachainInfoConfig { parachain_id: id }),
+	}
+}
+
+fn contracts_testnet_genesis(
+	root_key: AccountId,
+	endowed_accounts: Vec<AccountId>,
+	id: ParaId,
+) -> parachain_contracts_runtime::GenesisConfig {
+	parachain_contracts_runtime::GenesisConfig {
+		frame_system: Some(parachain_contracts_runtime::SystemConfig {
+			code: parachain_contracts_runtime::WASM_BINARY
+				.expect("WASM binary was not build, please build it!")
+				.to_vec(),
+			changes_trie_config: Default::default(),
+		}),
+		pallet_balances: Some(parachain_contracts_runtime::BalancesConfig {
+			balances: endowed_accounts
+				.iter()
+				.cloned()
+				.map(|k| (k, 1 << 60))
+				.collect(),
+		}),
+		pallet_sudo: Some(parachain_contracts_runtime::SudoConfig { key: root_key }),
+		parachain_info: Some(parachain_contracts_runtime::ParachainInfoConfig { parachain_id: id }),
+		cumulus_pallet_contracts: None,
 	}
 }
@@ -24,8 +24,8 @@ use log::info;
 use parachain_runtime::Block;
 use polkadot_parachain::primitives::AccountIdConversion;
 use sc_cli::{
-	ChainSpec, CliConfiguration, ImportParams, KeystoreParams, NetworkParams, Result,
-	RuntimeVersion, SharedParams, SubstrateCli, DefaultConfigurationValues,
+	ChainSpec, CliConfiguration, DefaultConfigurationValues, ImportParams, KeystoreParams,
+	NetworkParams, Result, RuntimeVersion, SharedParams, SubstrateCli,
 };
 use sc_service::config::{BasePath, PrometheusConfig};
 use sp_core::hexdisplay::HexDisplay;
@@ -77,6 +77,9 @@ impl SubstrateCli for Cli {
 			"track" => Ok(Box::new(chain_spec::ChainSpec::from_json_bytes(
 				&include_bytes!("../res/track.json")[..],
 			)?)),
+			"contracts" => Ok(Box::new(chain_spec::get_contracts_chain_spec(
+				self.run.parachain_id.unwrap_or(100).into(),
+			))),
 			"" => Ok(Box::new(chain_spec::get_chain_spec(
 				self.run.parachain_id.unwrap_or(100).into(),
 			))),
@@ -167,6 +170,10 @@ fn extract_genesis_wasm(chain_spec: &Box<dyn sc_service::ChainSpec>) -> Result<V
 		.ok_or_else(|| "Could not find wasm file in genesis state!".into())
 }

+fn use_contracts_runtime(chain_spec: &Box<dyn ChainSpec>) -> bool {
+	chain_spec.id().starts_with("trick") || chain_spec.id().starts_with("contracts")
+}
+
 /// Parse command line arguments into service configuration.
 pub fn run() -> Result<()> {
 	let cli = Cli::from_args();
@@ -175,8 +182,12 @@ pub fn run() -> Result<()> {
 		Some(Subcommand::Base(subcommand)) => {
 			let runner = cli.create_runner(subcommand)?;

+			if use_contracts_runtime(&runner.config().chain_spec) {
 				runner.run_subcommand(subcommand, |mut config| {
-				let params = crate::service::new_partial(&mut config)?;
+					let params = crate::service::new_partial::<
+						parachain_contracts_runtime::RuntimeApi,
+						crate::service::ContractsRuntimeExecutor,
+					>(&mut config)?;

 					Ok((
 						params.client,
@@ -185,6 +196,21 @@ pub fn run() -> Result<()> {
 						params.task_manager,
 					))
 				})
+			} else {
+				runner.run_subcommand(subcommand, |mut config| {
+					let params = crate::service::new_partial::<
+						parachain_runtime::RuntimeApi,
+						crate::service::RuntimeExecutor,
+					>(&mut config)?;
+
+					Ok((
+						params.client,
+						params.backend,
+						params.import_queue,
+						params.task_manager,
+					))
+				})
+			}
 		}
 		Some(Subcommand::ExportGenesisState(params)) => {
 			sc_cli::init_logger("");
@@ -256,14 +282,23 @@ pub fn run() -> Result<()> {
 					if cli.run.base.validator { "yes" } else { "no" }
 				);

-				crate::service::run_node(
+				if use_contracts_runtime(&config.chain_spec) {
+					crate::service::start_contracts_node(
 						config,
 						key,
 						polkadot_config,
 						id,
 						cli.run.base.validator,
 					)
-				.map(|(x, _)| x)
+				} else {
+					crate::service::start_node(
+						config,
+						key,
+						polkadot_config,
+						id,
+						cli.run.base.validator,
+					).map(|r| r.0)
+				}
 			})
 		}
 	}
@@ -60,7 +60,8 @@ async fn integration_test() {
 		INTEGRATION_TEST_ALLOWED_TIME
 			.and_then(|x| x.parse().ok())
 			.unwrap_or(600),
-	)).fuse();
+	))
+	.fuse();

 	let t2 = async {
 		let para_id = ParaId::from(100);
@@ -105,7 +106,7 @@ async fn integration_test() {
 		let parachain_config =
 			parachain_config(task_executor.clone(), Charlie, vec![], para_id).unwrap();
 		let (_service, charlie_client) =
-			crate::service::run_node(parachain_config, key, polkadot_config, para_id, true)
+			crate::service::start_node(parachain_config, key, polkadot_config, para_id, true)
 				.unwrap();
 		sleep(Duration::from_secs(3)).await;
 		charlie_client.wait_for_blocks(4).await;
@@ -20,67 +20,74 @@ use cumulus_service::{
 	prepare_node_config, start_collator, start_full_node, StartCollatorParams, StartFullNodeParams,
 };
 use polkadot_primitives::v0::CollatorPair;
+use rococo_parachain_primitives::Block;
 use sc_executor::native_executor_instance;
 pub use sc_executor::NativeExecutor;
 use sc_informant::OutputFormat;
 use sc_service::{Configuration, PartialComponents, Role, TFullBackend, TFullClient, TaskManager};
+use sp_api::ConstructRuntimeApi;
 use sp_runtime::traits::BlakeTwo256;
 use sp_trie::PrefixedMemoryDB;
 use std::sync::Arc;

-// Our native executor instance.
+// Native executor instance.
 native_executor_instance!(
-	pub Executor,
+	pub RuntimeExecutor,
 	parachain_runtime::api::dispatch,
 	parachain_runtime::native_version,
 );

+// Native executor instance for the contracts runtime.
+native_executor_instance!(
+	pub ContractsRuntimeExecutor,
+	parachain_contracts_runtime::api::dispatch,
+	parachain_contracts_runtime::native_version,
+);
+
 /// Starts a `ServiceBuilder` for a full service.
 ///
 /// Use this macro if you don't actually need the full service, but just the builder in order to
 /// be able to perform chain operations.
-pub fn new_partial(
+pub fn new_partial<RuntimeApi, Executor>(
 	config: &mut Configuration,
 ) -> Result<
 	PartialComponents<
-		TFullClient<
-			parachain_runtime::opaque::Block,
-			parachain_runtime::RuntimeApi,
-			crate::service::Executor,
-		>,
-		TFullBackend<parachain_runtime::opaque::Block>,
+		TFullClient<Block, RuntimeApi, Executor>,
+		TFullBackend<Block>,
 		(),
-		sp_consensus::import_queue::BasicQueue<
-			parachain_runtime::opaque::Block,
-			PrefixedMemoryDB<BlakeTwo256>,
-		>,
-		sc_transaction_pool::FullPool<
-			parachain_runtime::opaque::Block,
-			TFullClient<
-				parachain_runtime::opaque::Block,
-				parachain_runtime::RuntimeApi,
-				crate::service::Executor,
-			>,
-		>,
+		sp_consensus::import_queue::BasicQueue<Block, PrefixedMemoryDB<BlakeTwo256>>,
+		sc_transaction_pool::FullPool<Block, TFullClient<Block, RuntimeApi, Executor>>,
 		(),
 	>,
 	sc_service::Error,
-> {
+>
+where
+	RuntimeApi: ConstructRuntimeApi<Block, TFullClient<Block, RuntimeApi, Executor>>
+		+ Send
+		+ Sync
+		+ 'static,
+	RuntimeApi::RuntimeApi: sp_transaction_pool::runtime_api::TaggedTransactionQueue<Block>
+		+ sp_api::Metadata<Block>
+		+ sp_session::SessionKeys<Block>
+		+ sp_api::ApiExt<
+			Block,
+			Error = sp_blockchain::Error,
+			StateBackend = sc_client_api::StateBackendFor<TFullBackend<Block>, Block>,
+		> + sp_offchain::OffchainWorkerApi<Block>
+		+ sp_block_builder::BlockBuilder<Block>,
+	sc_client_api::StateBackendFor<TFullBackend<Block>, Block>: sp_api::StateBackend<BlakeTwo256>,
+	Executor: sc_executor::NativeExecutionDispatch + 'static,
+{
 	let inherent_data_providers = sp_inherents::InherentDataProviders::new();

-	let (client, backend, keystore, task_manager) = sc_service::new_full_parts::<
-		parachain_runtime::opaque::Block,
-		parachain_runtime::RuntimeApi,
-		crate::service::Executor,
-	>(&config)?;
+	let (client, backend, keystore, task_manager) =
+		sc_service::new_full_parts::<Block, RuntimeApi, Executor>(&config)?;
 	let client = Arc::new(client);
-	//let select_chain = sc_consensus::LongestChain::new(backend.clone());

 	let registry = config.prometheus_registry();

 	let transaction_pool = sc_transaction_pool::BasicPool::new_full(
 		config.transaction_pool.clone(),
-		//std::sync::Arc::new(pool_api),
 		config.prometheus_registry(),
 		task_manager.spawn_handle(),
 		client.clone(),
@@ -109,25 +116,39 @@ pub fn new_partial(
 	Ok(params)
 }

-/// Run a node with the given parachain `Configuration` and relay chain `Configuration`
+/// Start a node with the given parachain `Configuration` and relay chain `Configuration`.
 ///
-/// This function blocks until done.
-pub fn run_node(
+/// This is the actual implementation that is abstract over the executor and the runtime api.
+fn start_node_impl<RuntimeApi, Executor, RB>(
 	parachain_config: Configuration,
 	collator_key: Arc<CollatorPair>,
 	mut polkadot_config: polkadot_collator::Configuration,
 	id: polkadot_primitives::v0::Id,
 	validator: bool,
-) -> sc_service::error::Result<(
-	TaskManager,
-	Arc<
-		TFullClient<
-			parachain_runtime::opaque::Block,
-			parachain_runtime::RuntimeApi,
-			crate::service::Executor,
-		>,
-	>,
-)> {
+	rpc_ext_builder: RB,
+) -> sc_service::error::Result<(TaskManager, Arc<TFullClient<Block, RuntimeApi, Executor>>)>
+where
+	RuntimeApi: ConstructRuntimeApi<Block, TFullClient<Block, RuntimeApi, Executor>>
+		+ Send
+		+ Sync
+		+ 'static,
+	RuntimeApi::RuntimeApi: sp_transaction_pool::runtime_api::TaggedTransactionQueue<Block>
+		+ sp_api::Metadata<Block>
+		+ sp_session::SessionKeys<Block>
+		+ sp_api::ApiExt<
+			Block,
+			Error = sp_blockchain::Error,
+			StateBackend = sc_client_api::StateBackendFor<TFullBackend<Block>, Block>,
+		> + sp_offchain::OffchainWorkerApi<Block>
+		+ sp_block_builder::BlockBuilder<Block>,
+	sc_client_api::StateBackendFor<TFullBackend<Block>, Block>: sp_api::StateBackend<BlakeTwo256>,
+	Executor: sc_executor::NativeExecutionDispatch + 'static,
+	RB: Fn(
+			Arc<TFullClient<Block, RuntimeApi, Executor>>,
+		) -> jsonrpc_core::IoHandler<sc_rpc::Metadata>
+		+ Send
+		+ 'static,
+{
 	if matches!(parachain_config.role, Role::Light) {
 		return Err("Light client not supported!".into());
 	}
@@ -143,7 +164,7 @@ pub fn run_node(
 		prefix: format!("[{}] ", Color::Blue.bold().paint("Relaychain")),
 	};

-	let params = new_partial(&mut parachain_config)?;
+	let params = new_partial::<RuntimeApi, Executor>(&mut parachain_config)?;
 	params
 		.inherent_data_providers
 		.register_provider(sp_timestamp::InherentDataProvider)
@@ -175,20 +196,9 @@ pub fn run_node(
 		})?;

 	let rpc_extensions_builder = {
-		let _client = client.clone();
+		let client = client.clone();

-		Box::new(move |_deny_unsafe| {
-			let io = jsonrpc_core::IoHandler::default();
-
-			// TODO: add this rpc when running the contracts runtime
-			/*
-			use pallet_contracts_rpc::{Contracts, ContractsApi};
-			io.extend_with(
-				ContractsApi::to_delegate(Contracts::new(client.clone()))
-			);
-			*/
-			io
-		})
+		Box::new(move |_deny_unsafe| rpc_ext_builder(client.clone()))
 	};

 	sc_service::spawn_tasks(sc_service::SpawnTasksParams {
@@ -249,3 +259,49 @@ pub fn run_node(

 	Ok((task_manager, client))
 }
+
+/// Start a normal parachain node.
+pub fn start_node(
+	parachain_config: Configuration,
+	collator_key: Arc<CollatorPair>,
+	polkadot_config: polkadot_collator::Configuration,
+	id: polkadot_primitives::v0::Id,
+	validator: bool,
+) -> sc_service::error::Result<(
+	TaskManager,
+	Arc<TFullClient<Block, parachain_runtime::RuntimeApi, RuntimeExecutor>>,
+)> {
+	start_node_impl::<parachain_runtime::RuntimeApi, RuntimeExecutor, _>(
+		parachain_config,
+		collator_key,
+		polkadot_config,
+		id,
+		validator,
+		|_| Default::default(),
+	)
+}
+
+/// Start a contracts parachain node.
+pub fn start_contracts_node(
+	parachain_config: Configuration,
+	collator_key: Arc<CollatorPair>,
+	polkadot_config: polkadot_collator::Configuration,
+	id: polkadot_primitives::v0::Id,
+	validator: bool,
+) -> sc_service::error::Result<TaskManager> {
+	start_node_impl::<parachain_contracts_runtime::RuntimeApi, ContractsRuntimeExecutor, _>(
+		parachain_config,
+		collator_key,
+		polkadot_config,
+		id,
+		validator,
+		|client| {
+			let mut io = jsonrpc_core::IoHandler::default();
+
+			use cumulus_pallet_contracts_rpc::{Contracts, ContractsApi};
+			io.extend_with(ContractsApi::to_delegate(Contracts::new(client)));
+			io
+		},
+	)
+	.map(|r| r.0)
+}
@@ -51,7 +51,9 @@ static mut STORAGE: Option<Box<dyn Storage>> = None;
 /// Panics if the [`STORAGE`] is not initialized.
 fn with_storage<R>(call: impl FnOnce(&mut dyn Storage) -> R) -> R {
 	let mut storage = unsafe {
-		STORAGE.take().expect("`STORAGE` needs to be set before calling this function.")
+		STORAGE
+			.take()
+			.expect("`STORAGE` needs to be set before calling this function.")
 	};

 	let res = call(&mut *storage);
@@ -142,7 +144,8 @@ pub fn validate_block<B: BlockT, E: ExecuteBlock<B>>(params: ValidationParams) -

 	// If in the course of block execution new validation code was set, insert
 	// its scheduled upgrade so we can validate that block number later.
-	let new_validation_code = with_storage(|storage| storage.get(NEW_VALIDATION_CODE)).map(ValidationCode);
+	let new_validation_code =
+		with_storage(|storage| storage.get(NEW_VALIDATION_CODE)).map(ValidationCode);
 	if new_validation_code.is_some() && validation_function_params.code_upgrade_allowed.is_none() {
 		panic!("Attempt to upgrade validation function when not permitted!");
 	}
@@ -154,7 +157,8 @@ pub fn validate_block<B: BlockT, E: ExecuteBlock<B>>(params: ValidationParams) -
 		None => Vec::new(),
 	};

-	let processed_downward_messages = with_storage(|storage| storage.get(PROCESSED_DOWNWARD_MESSAGES))
+	let processed_downward_messages =
+		with_storage(|storage| storage.get(PROCESSED_DOWNWARD_MESSAGES))
 			.and_then(|v| Decode::decode(&mut &v[..]).ok())
 			.unwrap_or_default();

@@ -266,13 +270,11 @@ impl<B: BlockT> Storage for WitnessStorage<B> {
 		let witness_data = &self.witness_data;
 		let storage_root = &self.storage_root;

-		let current_value = overlay.entry(key.to_vec()).or_insert_with(||
-			read_trie_value::<Layout<HashFor<B>>, _>(
-				witness_data,
-				storage_root,
-				key,
-			).ok().flatten()
-		);
+		let current_value = overlay.entry(key.to_vec()).or_insert_with(|| {
+			read_trie_value::<Layout<HashFor<B>>, _>(witness_data, storage_root, key)
+				.ok()
+				.flatten()
+		});

 		let item = current_value.take().unwrap_or_default();
 		*current_value = Some(
@@ -130,7 +130,7 @@ fn build_block_with_proof(
 		built_block.block,
 		built_block
 			.proof
-			.expect("We enabled proof recording before.")
+			.expect("We enabled proof recording before."),
 	)
 }