Cleanup transaction pool deps (#4782)

* Cleanup transaction pool deps

* Fix it properly

* Fix doc test

substrate/Cargo.lock

@@ -5409,6 +5409,7 @@ dependencies = [
  "sp-runtime 2.0.0",
  "sp-transaction-pool 2.0.0",
  "substrate-test-runtime-client 2.0.0",
+ "substrate-test-runtime-transaction-pool 2.0.0",
  "tempfile 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "tokio 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -5985,6 +5986,7 @@ dependencies = [
  "sp-runtime 2.0.0",
  "sp-transaction-pool 2.0.0",
  "substrate-test-runtime-client 2.0.0",
+ "substrate-test-runtime-transaction-pool 2.0.0",
 ]
 
 [[package]]
@@ -7103,6 +7105,20 @@ dependencies = [
  "substrate-test-runtime 2.0.0",
 ]
 
+[[package]]
+name = "substrate-test-runtime-transaction-pool"
+version = "2.0.0"
+dependencies = [
+ "derive_more 0.99.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "futures 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "parity-scale-codec 1.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "parking_lot 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "sc-transaction-graph 2.0.0",
+ "sp-runtime 2.0.0",
+ "sp-transaction-pool 2.0.0",
+ "substrate-test-runtime-client 2.0.0",
+]
+
 [[package]]
 name = "substrate-test-utils"
 version = "2.0.0"

substrate/Cargo.toml

@@ -147,6 +147,7 @@ members = [
 	"test-utils/client",
 	"test-utils/runtime",
 	"test-utils/runtime/client",
+	"test-utils/runtime/transaction-pool",
 	"utils/browser",
 	"utils/build-script-utils",
 	"utils/fork-tree",

substrate/bin/node-template/src/service.rs

@@ -41,7 +41,7 @@ macro_rules! new_full_start {
 			})?
 			.with_transaction_pool(|config, client, _fetcher| {
 				let pool_api = sc_transaction_pool::FullChainApi::new(client.clone());
-				let pool = sc_transaction_pool::BasicPool::new(config, pool_api);
+				let pool = sc_transaction_pool::BasicPool::new(config, std::sync::Arc::new(pool_api));
 				Ok(pool)
 			})?
 			.with_import_queue(|_config, client, mut select_chain, transaction_pool| {
@@ -207,7 +207,7 @@ pub fn new_light(config: Configuration<GenesisConfig>)
 
 			let pool_api = sc_transaction_pool::LightChainApi::new(client.clone(), fetcher.clone());
 			let pool = sc_transaction_pool::BasicPool::with_revalidation_type(
-				config, pool_api, sc_transaction_pool::RevalidationType::Light,
+				config, Arc::new(pool_api), sc_transaction_pool::RevalidationType::Light,
 			);
 			Ok(pool)
 		})?

substrate/bin/node/cli/src/service.rs

@@ -63,7 +63,7 @@ macro_rules! new_full_start {
 			})?
 			.with_transaction_pool(|config, client, _fetcher| {
 				let pool_api = sc_transaction_pool::FullChainApi::new(client.clone());
-				let pool = sc_transaction_pool::BasicPool::new(config, pool_api);
+				let pool = sc_transaction_pool::BasicPool::new(config, std::sync::Arc::new(pool_api));
 				Ok(pool)
 			})?
 			.with_import_queue(|_config, client, mut select_chain, _transaction_pool| {
@@ -313,7 +313,7 @@ pub fn new_light(config: NodeConfiguration)
 				.ok_or_else(|| "Trying to start light transaction pool without active fetcher")?;
 			let pool_api = sc_transaction_pool::LightChainApi::new(client.clone(), fetcher.clone());
 			let pool = sc_transaction_pool::BasicPool::with_revalidation_type(
-				config, pool_api, sc_transaction_pool::RevalidationType::Light,
+				config, Arc::new(pool_api), sc_transaction_pool::RevalidationType::Light,
 			);
 			Ok(pool)
 		})?

substrate/client/basic-authorship/src/basic_authorship.rs

@@ -306,7 +306,9 @@ mod tests {
 	fn should_cease_building_block_when_deadline_is_reached() {
 		// given
 		let client = Arc::new(substrate_test_runtime_client::new());
-		let txpool = Arc::new(BasicPool::new(Default::default(), FullChainApi::new(client.clone())));
+		let txpool = Arc::new(
+			BasicPool::new(Default::default(), Arc::new(FullChainApi::new(client.clone())))
+		);
 
 		futures::executor::block_on(
 			txpool.submit_at(&BlockId::number(0), vec![extrinsic(0), extrinsic(1)])
@@ -346,7 +348,9 @@ mod tests {
 		let (client, backend) = substrate_test_runtime_client::TestClientBuilder::new()
 			.build_with_backend();
 		let client = Arc::new(client);
-		let txpool = Arc::new(BasicPool::new(Default::default(), FullChainApi::new(client.clone())));
+		let txpool = Arc::new(
+			BasicPool::new(Default::default(), Arc::new(FullChainApi::new(client.clone())))
+		);
 		let genesis_hash = client.info().best_hash;
 		let block_id = BlockId::Hash(genesis_hash);
 

substrate/client/basic-authorship/src/lib.rs

@@ -26,7 +26,7 @@
 //! # use substrate_test_runtime_client::{self, runtime::{Extrinsic, Transfer}, AccountKeyring};
 //! # use sc_transaction_pool::{BasicPool, FullChainApi};
 //! # let client = Arc::new(substrate_test_runtime_client::new());
-//! # let txpool = Arc::new(BasicPool::new(Default::default(), FullChainApi::new(client.clone())));
+//! # let txpool = Arc::new(BasicPool::new(Default::default(), Arc::new(FullChainApi::new(client.clone()))));
 //! // The first step is to create a `ProposerFactory`.
 //! let mut proposer_factory = ProposerFactory {
 //! 	client: client.clone(),

substrate/client/consensus/manual-seal/Cargo.toml

@@ -18,7 +18,7 @@ serde = { version = "1.0", features=["derive"] }
 
 sc-client = { path = "../../../client" }
 sc-client-api = { path = "../../../client/api" }
-sc-transaction-pool = { path = "../../transaction-pool", features = ["test-helpers"] }
+sc-transaction-pool = { path = "../../transaction-pool" }
 sp-blockchain = { path = "../../../primitives/blockchain" }
 sp-consensus = { package = "sp-consensus", path = "../../../primitives/consensus/common" }
 sp-inherents = { path = "../../../primitives/inherents" }
@@ -28,6 +28,7 @@ sp-transaction-pool = { path = "../../../primitives/transaction-pool" }
 [dev-dependencies]
 sc-basic-authorship = { path = "../../basic-authorship" }
 substrate-test-runtime-client = { path = "../../../test-utils/runtime/client" }
+substrate-test-runtime-transaction-pool = { path = "../../../test-utils/runtime/transaction-pool" }
 tokio = { version = "0.2", features = ["rt-core", "macros"] }
 env_logger = "0.7.0"
 tempfile = "3.1.0"

substrate/client/consensus/manual-seal/src/lib.rs

@@ -231,8 +231,8 @@ mod tests {
 	use sc_transaction_pool::{
 		BasicPool,
 		txpool::Options,
-		testing::api::*,
 	};
+	use substrate_test_runtime_transaction_pool::{TestApi, uxt};
 	use sp_transaction_pool::TransactionPool;
 	use sp_runtime::generic::BlockId;
 	use sp_blockchain::HeaderBackend;
@@ -241,8 +241,8 @@ mod tests {
 	use sp_inherents::InherentDataProviders;
 	use sc_basic_authorship::ProposerFactory;
 
-	fn api() -> TestApi {
-		TestApi::empty()
+	fn api() -> Arc<TestApi> {
+		Arc::new(TestApi::empty())
 	}
 
 	#[tokio::test]
@@ -385,7 +385,8 @@ mod tests {
 		let client = Arc::new(builder.build());
 		let select_chain = LongestChain::new(backend.clone());
 		let inherent_data_providers = InherentDataProviders::new();
-		let pool = Arc::new(BasicPool::new(Options::default(), api()));
+		let pool_api = api();
+		let pool = Arc::new(BasicPool::new(Options::default(), pool_api.clone()));
 		let env = ProposerFactory {
 			transaction_pool: pool.clone(),
 			client: client.clone(),
@@ -419,7 +420,7 @@ mod tests {
 			finalize: false,
 		}).await.unwrap();
 		let created_block = rx.await.unwrap().unwrap();
-		pool.api().increment_nonce(Alice.into());
+		pool_api.increment_nonce(Alice.into());
 
 		// assert that the background task returns ok
 		assert_eq!(
@@ -449,7 +450,7 @@ mod tests {
 		}).await.is_ok());
 		assert!(rx1.await.unwrap().is_ok());
 		assert!(backend.blockchain().header(BlockId::Number(1)).unwrap().is_some());
-		pool.api().increment_nonce(Alice.into());
+		pool_api.increment_nonce(Alice.into());
 
 		assert!(pool.submit_one(&BlockId::Number(2), uxt(Alice, 2)).await.is_ok());
 		let (tx2, rx2) = futures::channel::oneshot::channel();

substrate/client/offchain/src/lib.rs

@@ -202,7 +202,10 @@ mod tests {
 		// given
 		let _ = env_logger::try_init();
 		let client = Arc::new(substrate_test_runtime_client::new());
-		let pool = Arc::new(TestPool(BasicPool::new(Default::default(), FullChainApi::new(client.clone()))));
+		let pool = Arc::new(TestPool(BasicPool::new(
+			Default::default(),
+			Arc::new(FullChainApi::new(client.clone())),
+		)));
 		client.execution_extensions()
 			.register_transaction_pool(Arc::downgrade(&pool.clone()) as _);
 		let db = sc_client_db::offchain::LocalStorage::new_test();

substrate/client/rpc/src/author/tests.rs

@@ -56,8 +56,15 @@ struct TestSetup {
 impl Default for TestSetup {
 	fn default() -> Self {
 		let keystore = KeyStore::new();
-		let client = Arc::new(substrate_test_runtime_client::TestClientBuilder::new().set_keystore(keystore.clone()).build());
-		let pool = Arc::new(BasicPool::new(Default::default(), FullChainApi::new(client.clone())));
+		let client = Arc::new(
+			substrate_test_runtime_client::TestClientBuilder::new()
+				.set_keystore(keystore.clone())
+				.build()
+		);
+		let pool = Arc::new(BasicPool::new(
+			Default::default(),
+			Arc::new(FullChainApi::new(client.clone())),
+		));
 		TestSetup {
 			runtime: runtime::Runtime::new().expect("Failed to create runtime in test setup"),
 			client,

substrate/client/rpc/src/state/state_full.rs

@@ -36,7 +36,6 @@ use sp_core::{
 	Bytes, storage::{well_known_keys, StorageKey, StorageData, StorageChangeSet, ChildInfo},
 };
 use sp_version::RuntimeVersion;
-use sp_state_machine::ExecutionStrategy;
 use sp_runtime::{
 	generic::BlockId, traits::{Block as BlockT, NumberFor, SaturatedConversion},
 };

substrate/client/service/src/lib.rs

@@ -700,7 +700,10 @@ mod tests {
 		// given
 		let (client, longest_chain) = TestClientBuilder::new().build_with_longest_chain();
 		let client = Arc::new(client);
-		let pool = Arc::new(BasicPool::new(Default::default(), FullChainApi::new(client.clone())));
+		let pool = Arc::new(BasicPool::new(
+			Default::default(),
+			Arc::new(FullChainApi::new(client.clone())),
+		));
 		let best = longest_chain.best_chain().unwrap();
 		let transaction = Transfer {
 			amount: 5,

substrate/client/transaction-pool/Cargo.toml

@@ -12,17 +12,15 @@ futures = { version = "0.3.1", features = ["compat"] }
 futures-diagnose = "1.0"
 log = "0.4.8"
 parking_lot = "0.9.0"
-sp-core = { path = "../../primitives/core" }
-sp-api = { path = "../../primitives/api" }
-sp-runtime = { path = "../../primitives/runtime" }
-sc-transaction-graph = { path = "./graph" }
-sp-transaction-pool = { path = "../../primitives/transaction-pool" }
-sc-client-api = { path = "../api" }
-sp-blockchain = { path = "../../primitives/blockchain" }
-substrate-test-runtime-client = { path = "../../test-utils/runtime/client" }
+sp-core = { version = "2.0.0", path = "../../primitives/core" }
+sp-api = { version = "2.0.0", path = "../../primitives/api" }
+sp-runtime = { version = "2.0.0", path = "../../primitives/runtime" }
+sc-transaction-graph = { version = "2.0.0", path = "./graph" }
+sp-transaction-pool = { version = "2.0.0", path = "../../primitives/transaction-pool" }
+sc-client-api = { version = "2.0.0", path = "../api" }
+sp-blockchain = { version = "2.0.0", path = "../../primitives/blockchain" }
 
 [dev-dependencies]
 sp-keyring = { version = "2.0.0", path = "../../primitives/keyring" }
-
-[features]
-test-helpers = []
+substrate-test-runtime-transaction-pool = { version = "2.0.0", path = "../../test-utils/runtime/transaction-pool" }
+substrate-test-runtime-client = { version = "2.0.0", path = "../../test-utils/runtime/client" }

substrate/client/transaction-pool/src/lib.rs

@@ -42,8 +42,6 @@ use sp_transaction_pool::{
 	MaintainedTransactionPool, PoolFuture,
 };
 
-type PoolResult<T> = PoolFuture<T, error::Error>;
-
 /// Basic implementation of transaction pool that can be customized by providing PoolApi.
 pub struct BasicPool<PoolApi, Block>
 	where
@@ -80,7 +78,7 @@ impl<PoolApi, Block> BasicPool<PoolApi, Block>
 	/// Create new basic transaction pool with provided api.
 	pub fn new(
 		options: sc_transaction_graph::Options,
-		pool_api: PoolApi,
+		pool_api: Arc<PoolApi>,
 	) -> Self {
 		Self::with_revalidation_type(options, pool_api, RevalidationType::Full)
 	}
@@ -89,14 +87,13 @@ impl<PoolApi, Block> BasicPool<PoolApi, Block>
 	/// revalidation type.
 	pub fn with_revalidation_type(
 		options: sc_transaction_graph::Options,
-		pool_api: PoolApi,
+		pool_api: Arc<PoolApi>,
 		revalidation_type: RevalidationType,
 	) -> Self {
-		let api = Arc::new(pool_api);
-		let cloned_api = api.clone();
+		let cloned_api = pool_api.clone();
 		BasicPool {
 			api: cloned_api,
-			pool: Arc::new(sc_transaction_graph::Pool::new(options, api)),
+			pool: Arc::new(sc_transaction_graph::Pool::new(options, pool_api)),
 			revalidation_strategy: Arc::new(Mutex::new(
 				match revalidation_type {
 					RevalidationType::Light => RevalidationStrategy::Light(RevalidationStatus::NotScheduled),
@@ -111,29 +108,23 @@ impl<PoolApi, Block> BasicPool<PoolApi, Block>
 	pub fn pool(&self) -> &Arc<sc_transaction_graph::Pool<PoolApi>> {
 		&self.pool
 	}
-
-	/// Get reference to the inner chain api, for tests only.
-	#[cfg(any(feature = "test-helpers", test))]
-	pub fn api(&self) -> &Arc<PoolApi> {
-		&self.api
-	}
 }
 
 impl<PoolApi, Block> TransactionPool for BasicPool<PoolApi, Block>
 	where
 		Block: BlockT,
-		PoolApi: 'static + sc_transaction_graph::ChainApi<Block=Block, Hash=Block::Hash, Error=error::Error>,
+		PoolApi: 'static + sc_transaction_graph::ChainApi<Block=Block, Hash=Block::Hash>,
 {
 	type Block = PoolApi::Block;
 	type Hash = sc_transaction_graph::ExHash<PoolApi>;
 	type InPoolTransaction = sc_transaction_graph::base_pool::Transaction<TxHash<Self>, TransactionFor<Self>>;
-	type Error = error::Error;
+	type Error = PoolApi::Error;
 
 	fn submit_at(
 		&self,
 		at: &BlockId<Self::Block>,
 		xts: Vec<TransactionFor<Self>>,
-	) -> PoolResult<Vec<Result<TxHash<Self>, Self::Error>>> {
+	) -> PoolFuture<Vec<Result<TxHash<Self>, Self::Error>>, Self::Error> {
 		let pool = self.pool.clone();
 		let at = *at;
 		async move {
@@ -145,7 +136,7 @@ impl<PoolApi, Block> TransactionPool for BasicPool<PoolApi, Block>
 		&self,
 		at: &BlockId<Self::Block>,
 		xt: TransactionFor<Self>,
-	) -> PoolResult<TxHash<Self>> {
+	) -> PoolFuture<TxHash<Self>, Self::Error> {
 		let pool = self.pool.clone();
 		let at = *at;
 		async move {
@@ -157,7 +148,7 @@ impl<PoolApi, Block> TransactionPool for BasicPool<PoolApi, Block>
 		&self,
 		at: &BlockId<Self::Block>,
 		xt: TransactionFor<Self>,
-	) -> PoolResult<Box<TransactionStatusStreamFor<Self>>> {
+	) -> PoolFuture<Box<TransactionStatusStreamFor<Self>>, Self::Error> {
 		let at = *at;
 		let pool = self.pool.clone();
 
@@ -287,7 +278,7 @@ impl<N: Clone + Copy + SimpleArithmetic> RevalidationStatus<N> {
 impl<PoolApi, Block> MaintainedTransactionPool for BasicPool<PoolApi, Block>
 where
 	Block: BlockT,
-	PoolApi: 'static + sc_transaction_graph::ChainApi<Block=Block, Hash=Block::Hash, Error=error::Error>,
+	PoolApi: 'static + sc_transaction_graph::ChainApi<Block=Block, Hash=Block::Hash>,
 {
 	fn maintain(&self, id: &BlockId<Self::Block>, retracted: &[BlockHash<Self>])
 		-> Pin<Box<dyn Future<Output=()> + Send>>

substrate/client/transaction-pool/src/testing/mod.rs

@@ -16,8 +16,4 @@
 
 //! Tests for top-level transaction pool api
 
-#[cfg(any(feature = "test-helpers", test))]
-pub mod api;
-
-#[cfg(test)]
-mod pool;
+mod pool;

substrate/client/transaction-pool/src/testing/pool.rs

@@ -1,6 +1,21 @@
+// Copyright 2020 Parity Technologies (UK) Ltd.
+// This file is part of Substrate.
+
+// 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 Substrate.  If not, see <http://www.gnu.org/licenses/>.
 
 use crate::*;
-use sc_transaction_graph::{self, Pool};
+use sc_transaction_graph::Pool;
 use futures::executor::block_on;
 use sp_runtime::{
 	generic::BlockId,
@@ -10,14 +25,14 @@ use substrate_test_runtime_client::{
 	runtime::{Block, Hash, Index},
 	AccountKeyring::*,
 };
-use crate::testing::api::{TestApi, uxt};
+use substrate_test_runtime_transaction_pool::{TestApi, uxt};
 
 fn pool() -> Pool<TestApi> {
 	Pool::new(Default::default(), TestApi::with_alice_nonce(209).into())
 }
 
 fn maintained_pool() -> BasicPool<TestApi, Block> {
-	BasicPool::new(Default::default(), TestApi::with_alice_nonce(209))
+	BasicPool::new(Default::default(), std::sync::Arc::new(TestApi::with_alice_nonce(209)))
 }
 
 #[test]

substrate/test-utils/runtime/transaction-pool/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "substrate-test-runtime-transaction-pool"
+version = "2.0.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+license = "GPL-3.0"
+
+[dependencies]
+substrate-test-runtime-client = { version = "2.0.0", path = "../client" }
+parking_lot = "0.9.0"
+codec = { package = "parity-scale-codec", version = "1.0.0" }
+sp-runtime = { version = "2.0.0", path = "../../../primitives/runtime" }
+sp-transaction-pool = { version = "2.0.0", path = "../../../primitives/transaction-pool" }
+sc-transaction-graph = { version = "2.0.0", path = "../../../client/transaction-pool/graph" }
+futures = { version = "0.3.1", features = ["compat"] }
+derive_more = "0.99.2"

substrate/test-utils/runtime/transaction-pool/src/lib.rs

@@ -14,22 +14,41 @@
 // You should have received a copy of the GNU General Public License
 // along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
 
-//! Test ChainApi
+//! Test utils for the transaction pool together with the test runtime.
+//!
+//! See [`TestApi`] for more information.
 
-use crate::*;
 use codec::Encode;
 use parking_lot::RwLock;
 use sp_runtime::{
 	generic::{self, BlockId},
 	traits::{BlakeTwo256, Hash as HashT},
-	transaction_validity::{TransactionValidity, ValidTransaction, TransactionValidityError, InvalidTransaction},
+	transaction_validity::{
+		TransactionValidity, ValidTransaction, TransactionValidityError, InvalidTransaction,
+	},
 };
-use std::collections::HashSet;
+use std::collections::{HashSet, HashMap};
 use substrate_test_runtime_client::{
 	runtime::{Index, AccountId, Block, BlockNumber, Extrinsic, Hash, Header, Transfer},
 	AccountKeyring::{self, *},
 };
 
+/// Error type used by [`TestApi`].
+#[derive(Debug, derive_more::From, derive_more::Display)]
+pub struct Error(sp_transaction_pool::error::Error);
+
+impl sp_transaction_pool::error::IntoPoolError for Error {
+	fn into_pool_error(self) -> Result<sp_transaction_pool::error::Error, Self> {
+		Ok(self.0)
+	}
+}
+
+impl std::error::Error for Error {
+	fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+		Some(&self.0)
+	}
+}
+
 #[derive(Default)]
 struct ChainState {
 	pub block_by_number: HashMap<BlockNumber, Vec<Extrinsic>>,
@@ -47,7 +66,6 @@ pub struct TestApi {
 }
 
 impl TestApi {
-
 	/// Test Api with Alice nonce set initially.
 	pub fn with_alice_nonce(nonce: u64) -> Self {
 		let api = TestApi {
@@ -128,9 +146,9 @@ impl TestApi {
 impl sc_transaction_graph::ChainApi for TestApi {
 	type Block = Block;
 	type Hash = Hash;
-	type Error = error::Error;
-	type ValidationFuture = futures::future::Ready<error::Result<TransactionValidity>>;
-	type BodyFuture = futures::future::Ready<error::Result<Option<Vec<Extrinsic>>>>;
+	type Error = Error;
+	type ValidationFuture = futures::future::Ready<Result<TransactionValidity, Error>>;
+	type BodyFuture = futures::future::Ready<Result<Option<Vec<Extrinsic>>, Error>>;
 
 	fn validate_transaction(
 		&self,
@@ -149,7 +167,7 @@ impl sc_transaction_graph::ChainApi for TestApi {
 
 		if self.chain.read().invalid_hashes.contains(&self.hash_and_length(&uxt).0) {
 			return futures::future::ready(Ok(
-				Err(TransactionValidityError::Invalid(InvalidTransaction::Custom(0)))
+				Err(TransactionValidityError::Invalid(InvalidTransaction::Custom(0)).into())
 			))
 		}
 
@@ -169,14 +187,14 @@ impl sc_transaction_graph::ChainApi for TestApi {
 	fn block_id_to_number(
 		&self,
 		at: &BlockId<Self::Block>,
-	) -> error::Result<Option<sc_transaction_graph::NumberFor<Self>>> {
+	) -> Result<Option<sc_transaction_graph::NumberFor<Self>>, Error> {
 		Ok(Some(number_of(at)))
 	}
 
 	fn block_id_to_hash(
 		&self,
 		at: &BlockId<Self::Block>,
-	) -> error::Result<Option<sc_transaction_graph::BlockHash<Self>>> {
+	) -> Result<Option<sc_transaction_graph::BlockHash<Self>>, Error> {
 		Ok(match at {
 			generic::BlockId::Hash(x) => Some(x.clone()),
 			_ => Some(Default::default()),

substrate/utils/frame/rpc/system/src/lib.rs

@@ -235,7 +235,9 @@ mod tests {
 		// given
 		let _ = env_logger::try_init();
 		let client = Arc::new(substrate_test_runtime_client::new());
-		let pool = Arc::new(BasicPool::new(Default::default(), FullChainApi::new(client.clone())));
+		let pool = Arc::new(
+			BasicPool::new(Default::default(), Arc::new(FullChainApi::new(client.clone())))
+		);
 
 		let new_transaction = |nonce: u64| {
 			let t = Transfer {