diff --git a/polkadot/node/core/backing/src/tests/mod.rs b/polkadot/node/core/backing/src/tests/mod.rs
index a981487db4..4c2fd6becb 100644
--- a/polkadot/node/core/backing/src/tests/mod.rs
+++ b/polkadot/node/core/backing/src/tests/mod.rs
@@ -18,7 +18,7 @@ use self::test_helpers::mock::new_leaf;
 use super::*;
 use ::test_helpers::{
 	dummy_candidate_receipt_bad_sig, dummy_collator, dummy_collator_signature,
-	dummy_committed_candidate_receipt, dummy_hash,
+	dummy_committed_candidate_receipt, dummy_hash, validator_pubkeys,
 };
 use assert_matches::assert_matches;
 use futures::{future, Future};
@@ -48,10 +48,6 @@ mod prospective_parachains;
 const ASYNC_BACKING_DISABLED_ERROR: RuntimeApiError =
 	RuntimeApiError::NotSupported { runtime_api_name: "test-runtime" };
 
-fn validator_pubkeys(val_ids: &[Sr25519Keyring]) -> Vec<ValidatorId> {
-	val_ids.iter().map(|v| v.public().into()).collect()
-}
-
 fn table_statement_to_primitive(statement: TableStatement) -> Statement {
 	match statement {
 		TableStatement::Seconded(committed_candidate_receipt) =>
@@ -299,6 +295,81 @@ async fn test_startup(virtual_overseer: &mut VirtualOverseer, test_state: &TestS
 	);
 }
 
+async fn assert_validation_requests(
+	virtual_overseer: &mut VirtualOverseer,
+	validation_code: ValidationCode,
+) {
+	assert_matches!(
+		virtual_overseer.recv().await,
+		AllMessages::RuntimeApi(
+			RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
+		) if hash == validation_code.hash() => {
+			tx.send(Ok(Some(validation_code))).unwrap();
+		}
+	);
+
+	assert_matches!(
+		virtual_overseer.recv().await,
+		AllMessages::RuntimeApi(
+			RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
+		) => {
+			tx.send(Ok(1u32.into())).unwrap();
+		}
+	);
+
+	assert_matches!(
+		virtual_overseer.recv().await,
+		AllMessages::RuntimeApi(
+			RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
+		) if sess_idx == 1 => {
+			tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
+		}
+	);
+}
+
+async fn assert_validate_from_exhaustive(
+	virtual_overseer: &mut VirtualOverseer,
+	pvd: &PersistedValidationData,
+	pov: &PoV,
+	validation_code: &ValidationCode,
+	candidate: &CommittedCandidateReceipt,
+	expected_head_data: &HeadData,
+	result_validation_data: PersistedValidationData,
+) {
+	assert_matches!(
+		virtual_overseer.recv().await,
+		AllMessages::CandidateValidation(
+			CandidateValidationMessage::ValidateFromExhaustive(
+				_pvd,
+				_validation_code,
+				candidate_receipt,
+				_pov,
+				_,
+				timeout,
+				tx,
+			),
+		) if _pvd == *pvd &&
+			_validation_code == *validation_code &&
+			*_pov == *pov && &candidate_receipt.descriptor == candidate.descriptor() &&
+			timeout == PvfExecTimeoutKind::Backing &&
+			candidate.commitments.hash() == candidate_receipt.commitments_hash =>
+		{
+			tx.send(Ok(ValidationResult::Valid(
+				CandidateCommitments {
+					head_data: expected_head_data.clone(),
+					horizontal_messages: Default::default(),
+					upward_messages: Default::default(),
+					new_validation_code: None,
+					processed_downward_messages: 0,
+					hrmp_watermark: 0,
+				},
+				result_validation_data,
+			)))
+			.unwrap();
+		}
+	);
+}
+
 // Test that a `CandidateBackingMessage::Second` issues validation work
 // and in case validation is successful issues a `StatementDistributionMessage`.
 #[test]
@@ -334,65 +405,18 @@ fn backing_second_works() {
 
 		virtual_overseer.send(FromOrchestra::Communication { msg: second }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code.hash() => {
-				tx.send(Ok(Some(validation_code.clone()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code.clone()).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::CandidateValidation(
-				CandidateValidationMessage::ValidateFromExhaustive(
-					_pvd,
-					_validation_code,
-					candidate_receipt,
-					_pov,
-					_,
-					timeout,
-					tx,
-				),
-			) if _pvd == pvd &&
-				_validation_code == validation_code &&
-				*_pov == pov && &candidate_receipt.descriptor == candidate.descriptor() &&
-				timeout == PvfExecTimeoutKind::Backing &&
-				candidate.commitments.hash() == candidate_receipt.commitments_hash =>
-			{
-				tx.send(Ok(ValidationResult::Valid(
-					CandidateCommitments {
-						head_data: expected_head_data.clone(),
-						horizontal_messages: Default::default(),
-						upward_messages: Default::default(),
-						new_validation_code: None,
-						processed_downward_messages: 0,
-						hrmp_watermark: 0,
-					},
-					test_state.validation_data.clone(),
-				)))
-				.unwrap();
-			}
-		);
+		assert_validate_from_exhaustive(
+			&mut virtual_overseer,
+			&pvd,
+			&pov,
+			&validation_code,
+			&candidate,
+			expected_head_data,
+			test_state.validation_data.clone(),
+		)
+		.await;
 
 		assert_matches!(
 			virtual_overseer.recv().await,
@@ -499,32 +523,7 @@ fn backing_works() {
 
 		virtual_overseer.send(FromOrchestra::Communication { msg: statement }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code.hash() => {
-				tx.send(Ok(Some(validation_code.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code.clone()).await;
 
 		// Sending a `Statement::Seconded` for our assignment will start
 		// validation process. The first thing requested is the PoV.
@@ -702,32 +701,7 @@ fn backing_works_while_validation_ongoing() {
 			CandidateBackingMessage::Statement(test_state.relay_parent, signed_a.clone());
 		virtual_overseer.send(FromOrchestra::Communication { msg: statement }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code.hash() => {
-				tx.send(Ok(Some(validation_code.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code.clone()).await;
 
 		// Sending a `Statement::Seconded` for our assignment will start
 		// validation process. The first thing requested is PoV from the
@@ -893,32 +867,7 @@ fn backing_misbehavior_works() {
 
 		virtual_overseer.send(FromOrchestra::Communication { msg: statement }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code.hash() => {
-				tx.send(Ok(Some(validation_code.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code.clone()).await;
 
 		assert_matches!(
 			virtual_overseer.recv().await,
@@ -1098,32 +1047,7 @@ fn backing_dont_second_invalid() {
 
 		virtual_overseer.send(FromOrchestra::Communication { msg: second }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code_a.hash() => {
-				tx.send(Ok(Some(validation_code_a.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code_a.clone()).await;
 
 		assert_matches!(
 			virtual_overseer.recv().await,
@@ -1163,32 +1087,7 @@ fn backing_dont_second_invalid() {
 
 		virtual_overseer.send(FromOrchestra::Communication { msg: second }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code_b.hash() => {
-				tx.send(Ok(Some(validation_code_b.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code_b.clone()).await;
 
 		assert_matches!(
 			virtual_overseer.recv().await,
@@ -1300,32 +1199,7 @@ fn backing_second_after_first_fails_works() {
 
 		virtual_overseer.send(FromOrchestra::Communication { msg: statement }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code.hash() => {
-				tx.send(Ok(Some(validation_code.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code.clone()).await;
 
 		// Subsystem requests PoV and requests validation.
 		assert_matches!(
@@ -1408,32 +1282,7 @@ fn backing_second_after_first_fails_works() {
 		// triggered on the prev step.
 		virtual_overseer.send(FromOrchestra::Communication { msg: second }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code_to_second.hash() => {
-				tx.send(Ok(Some(validation_code_to_second.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code_to_second.clone()).await;
 
 		assert_matches!(
 			virtual_overseer.recv().await,
@@ -1494,32 +1343,7 @@ fn backing_works_after_failed_validation() {
 
 		virtual_overseer.send(FromOrchestra::Communication { msg: statement }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code.hash() => {
-				tx.send(Ok(Some(validation_code.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code.clone()).await;
 
 		// Subsystem requests PoV and requests validation.
 		assert_matches!(
@@ -1722,32 +1546,7 @@ fn retry_works() {
 			CandidateBackingMessage::Statement(test_state.relay_parent, signed_a.clone());
 		virtual_overseer.send(FromOrchestra::Communication { msg: statement }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code.hash() => {
-				tx.send(Ok(Some(validation_code.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code.clone()).await;
 
 		// Subsystem requests PoV and requests validation.
 		// We cancel - should mean retry on next backing statement.
@@ -1810,32 +1609,7 @@ fn retry_works() {
 			CandidateBackingMessage::Statement(test_state.relay_parent, signed_c.clone());
 		virtual_overseer.send(FromOrchestra::Communication { msg: statement }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code.hash() => {
-				tx.send(Ok(Some(validation_code.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code.clone()).await;
 
 		assert_matches!(
 			virtual_overseer.recv().await,
@@ -2026,65 +1800,18 @@ fn cannot_second_multiple_candidates_per_parent() {
 
 		virtual_overseer.send(FromOrchestra::Communication { msg: second }).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code.hash() => {
-				tx.send(Ok(Some(validation_code.clone()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code.clone()).await;
 
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::CandidateValidation(
-				CandidateValidationMessage::ValidateFromExhaustive(
-					_pvd,
-					_validation_code,
-					candidate_receipt,
-					_pov,
-					_,
-					timeout,
-					tx,
-				),
-			) if _pvd == pvd &&
-				_validation_code == validation_code &&
-				*_pov == pov && &candidate_receipt.descriptor == candidate.descriptor() &&
-				timeout == PvfExecTimeoutKind::Backing &&
-				candidate.commitments.hash() == candidate_receipt.commitments_hash =>
-			{
-				tx.send(Ok(ValidationResult::Valid(
-					CandidateCommitments {
-						head_data: expected_head_data.clone(),
-						horizontal_messages: Default::default(),
-						upward_messages: Default::default(),
-						new_validation_code: None,
-						processed_downward_messages: 0,
-						hrmp_watermark: 0,
-					},
-					test_state.validation_data.clone(),
-				)))
-				.unwrap();
-			}
-		);
+		assert_validate_from_exhaustive(
+			&mut virtual_overseer,
+			&pvd,
+			&pov,
+			&validation_code,
+			&candidate,
+			expected_head_data,
+			test_state.validation_data.clone(),
+		)
+		.await;
 
 		assert_matches!(
 			virtual_overseer.recv().await,
@@ -2131,32 +1858,7 @@ fn cannot_second_multiple_candidates_per_parent() {
 		virtual_overseer.send(FromOrchestra::Communication { msg: second }).await;
 
 		// The validation is still requested.
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-			) if hash == validation_code.hash() => {
-				tx.send(Ok(Some(validation_code.clone()))).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-			) => {
-				tx.send(Ok(1u32.into())).unwrap();
-			}
-		);
-
-		assert_matches!(
-			virtual_overseer.recv().await,
-			AllMessages::RuntimeApi(
-				RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-			) if sess_idx == 1 => {
-				tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-			}
-		);
+		assert_validation_requests(&mut virtual_overseer, validation_code.clone()).await;
 
 		assert_matches!(
 			virtual_overseer.recv().await,
diff --git a/polkadot/node/core/backing/src/tests/prospective_parachains.rs b/polkadot/node/core/backing/src/tests/prospective_parachains.rs
index d6e93fb04d..14f720b721 100644
--- a/polkadot/node/core/backing/src/tests/prospective_parachains.rs
+++ b/polkadot/node/core/backing/src/tests/prospective_parachains.rs
@@ -208,32 +208,7 @@ async fn assert_validate_seconded_candidate(
 	expected_head_data: &HeadData,
 	fetch_pov: bool,
 ) {
-	assert_matches!(
-		virtual_overseer.recv().await,
-		AllMessages::RuntimeApi(
-			RuntimeApiMessage::Request(parent, RuntimeApiRequest::ValidationCodeByHash(hash, tx))
-		) if parent == relay_parent && hash == validation_code.hash() => {
-			tx.send(Ok(Some(validation_code.clone()))).unwrap();
-		}
-	);
-
-	assert_matches!(
-		virtual_overseer.recv().await,
-		AllMessages::RuntimeApi(
-			RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionIndexForChild(tx))
-		) => {
-			tx.send(Ok(1u32.into())).unwrap();
-		}
-	);
-
-	assert_matches!(
-		virtual_overseer.recv().await,
-		AllMessages::RuntimeApi(
-			RuntimeApiMessage::Request(_, RuntimeApiRequest::SessionExecutorParams(sess_idx, tx))
-		) if sess_idx == 1 => {
-			tx.send(Ok(Some(ExecutorParams::default()))).unwrap();
-		}
-	);
+	assert_validation_requests(virtual_overseer, validation_code.clone()).await;
 
 	if fetch_pov {
 		assert_matches!(
diff --git a/polkadot/node/core/pvf-checker/src/tests.rs b/polkadot/node/core/pvf-checker/src/tests.rs
index bd8817000a..4ac6e5eba3 100644
--- a/polkadot/node/core/pvf-checker/src/tests.rs
+++ b/polkadot/node/core/pvf-checker/src/tests.rs
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.
 
-use ::test_helpers::{dummy_digest, dummy_hash};
+use ::test_helpers::{dummy_digest, dummy_hash, validator_pubkeys};
 use futures::{channel::oneshot, future::BoxFuture, prelude::*};
 use polkadot_node_subsystem::{
 	messages::{
@@ -94,10 +94,6 @@ struct TestState {
 
 const OUR_VALIDATOR: Sr25519Keyring = Sr25519Keyring::Alice;
 
-fn validator_pubkeys(val_ids: &[Sr25519Keyring]) -> Vec<ValidatorId> {
-	val_ids.iter().map(|v| v.public().into()).collect()
-}
-
 impl TestState {
 	fn new() -> Self {
 		// Initialize the default session 1. No validators are present there.
diff --git a/polkadot/primitives/test-helpers/src/lib.rs b/polkadot/primitives/test-helpers/src/lib.rs
index 8ee5f180d3..d532d6ff57 100644
--- a/polkadot/primitives/test-helpers/src/lib.rs
+++ b/polkadot/primitives/test-helpers/src/lib.rs
@@ -159,6 +159,11 @@ pub fn dummy_pvd(parent_head: HeadData, relay_parent_number: u32) -> PersistedVa
 	}
 }
 
+/// Creates a meaningless signature
+pub fn dummy_signature() -> polkadot_primitives::ValidatorSignature {
+	sp_core::crypto::UncheckedFrom::unchecked_from([1u8; 64])
+}
+
 /// Create a meaningless candidate, returning its receipt and PVD.
 pub fn make_candidate(
 	relay_parent_hash: Hash,
@@ -244,6 +249,11 @@ pub fn resign_candidate_descriptor_with_collator<H: AsRef<[u8]>>(
 	descriptor.signature = signature;
 }
 
+/// Extracts validators's public keus (`ValidatorId`) from `Sr25519Keyring`
+pub fn validator_pubkeys(val_ids: &[Sr25519Keyring]) -> Vec<ValidatorId> {
+	val_ids.iter().map(|v| v.public().into()).collect()
+}
+
 /// Builder for `CandidateReceipt`.
 pub struct TestCandidateBuilder {
 	pub para_id: ParaId,
@@ -298,7 +308,3 @@ impl rand::RngCore for AlwaysZeroRng {
 		Ok(())
 	}
 }
-
-pub fn dummy_signature() -> polkadot_primitives::ValidatorSignature {
-	sp_core::crypto::UncheckedFrom::unchecked_from([1u8; 64])
-}
diff --git a/polkadot/runtime/parachains/src/paras/tests.rs b/polkadot/runtime/parachains/src/paras/tests.rs
index a024525c81..c511c65d47 100644
--- a/polkadot/runtime/parachains/src/paras/tests.rs
+++ b/polkadot/runtime/parachains/src/paras/tests.rs
@@ -17,11 +17,11 @@
 use super::*;
 use frame_support::{assert_err, assert_ok, assert_storage_noop};
 use keyring::Sr25519Keyring;
-use primitives::{BlockNumber, ValidatorId, PARACHAIN_KEY_TYPE_ID};
+use primitives::{BlockNumber, PARACHAIN_KEY_TYPE_ID};
 use sc_keystore::LocalKeystore;
 use sp_keystore::{Keystore, KeystorePtr};
 use std::sync::Arc;
-use test_helpers::{dummy_head_data, dummy_validation_code};
+use test_helpers::{dummy_head_data, dummy_validation_code, validator_pubkeys};
 
 use crate::{
 	configuration::HostConfiguration,
@@ -39,10 +39,6 @@ static VALIDATORS: &[Sr25519Keyring] = &[
 	Sr25519Keyring::Ferdie,
 ];
 
-fn validator_pubkeys(val_ids: &[Sr25519Keyring]) -> Vec<ValidatorId> {
-	val_ids.iter().map(|v| v.public().into()).collect()
-}
-
 fn sign_and_include_pvf_check_statement(stmt: PvfCheckStatement) {
 	let validators = &[
 		Sr25519Keyring::Alice,
diff --git a/polkadot/runtime/parachains/src/shared/tests.rs b/polkadot/runtime/parachains/src/shared/tests.rs
index 91891ba8d7..ae12b4b3fc 100644
--- a/polkadot/runtime/parachains/src/shared/tests.rs
+++ b/polkadot/runtime/parachains/src/shared/tests.rs
@@ -22,10 +22,7 @@ use crate::{
 use assert_matches::assert_matches;
 use keyring::Sr25519Keyring;
 use primitives::Hash;
-
-fn validator_pubkeys(val_ids: &[Sr25519Keyring]) -> Vec<ValidatorId> {
-	val_ids.iter().map(|v| v.public().into()).collect()
-}
+use test_helpers::validator_pubkeys;
 
 #[test]
 fn tracker_earliest_block_number() {