Tests: Add require.Eventually and fix a few test flakes (#16217)

**What type of PR is this?** Other **What does this PR do? Why is it needed?** This is a better way to wait for a test condition to hit, rather than time.Sleep. **Which issues(s) does this PR fix?** **Other notes for review** **Acknowledgements** - [x] I have read [CONTRIBUTING.md](https://github.com/prysmaticlabs/prysm/blob/develop/CONTRIBUTING.md). - [x] I have included a uniquely named [changelog fragment file](https://github.com/prysmaticlabs/prysm/blob/develop/CONTRIBUTING.md#maintaining-changelogmd). - [x] I have added a description with sufficient context for reviewers to understand this PR. - [x] I have tested that my changes work as expected and I added a testing plan to the PR description (if applicable).
2026-01-07 20:43:57 -05:00 · 2026-01-06 12:20:27 -06:00
parent ffad861e2c
commit 27c009e7ff
12 changed files with 167 additions and 104 deletions
--- a/beacon-chain/blockchain/receive_block_test.go
+++ b/beacon-chain/blockchain/receive_block_test.go
@@ -17,6 +17,7 @@ import (
 	fieldparams "github.com/OffchainLabs/prysm/v7/config/fieldparams"
 	"github.com/OffchainLabs/prysm/v7/config/params"
 	"github.com/OffchainLabs/prysm/v7/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v7/consensus-types/interfaces"
 	"github.com/OffchainLabs/prysm/v7/consensus-types/primitives"
 	"github.com/OffchainLabs/prysm/v7/encoding/bytesutil"
 	ethpbv1 "github.com/OffchainLabs/prysm/v7/proto/eth/v1"
@@ -130,12 +131,10 @@ func TestService_ReceiveBlock(t *testing.T) {
 				block: genFullBlock(t, util.DefaultBlockGenConfig(), 1 /*slot*/),
 			},
 			check: func(t *testing.T, s *Service) {
-				// Hacky sleep, should use a better way to be able to resolve the race
-				// between event being sent out and processed.
-				time.Sleep(100 * time.Millisecond)
-				if recvd := len(s.cfg.StateNotifier.(*blockchainTesting.MockStateNotifier).ReceivedEvents()); recvd < 1 {
-					t.Errorf("Received %d state notifications, expected at least 1", recvd)
-				}
+				notifier := s.cfg.StateNotifier.(*blockchainTesting.MockStateNotifier)
+				require.Eventually(t, func() bool {
+					return len(notifier.ReceivedEvents()) >= 1
+				}, 2*time.Second, 10*time.Millisecond, "Expected at least 1 state notification")
 			},
 		},
 		{
@@ -222,10 +221,10 @@ func TestService_ReceiveBlockUpdateHead(t *testing.T) {
 		require.NoError(t, s.ReceiveBlock(ctx, wsb, root, nil))
 	})
 	wg.Wait()
-	time.Sleep(100 * time.Millisecond)
-	if recvd := len(s.cfg.StateNotifier.(*blockchainTesting.MockStateNotifier).ReceivedEvents()); recvd < 1 {
-		t.Errorf("Received %d state notifications, expected at least 1", recvd)
-	}
+	notifier := s.cfg.StateNotifier.(*blockchainTesting.MockStateNotifier)
+	require.Eventually(t, func() bool {
+		return len(notifier.ReceivedEvents()) >= 1
+	}, 2*time.Second, 10*time.Millisecond, "Expected at least 1 state notification")
 	// Verify fork choice has processed the block. (Genesis block and the new block)
 	assert.Equal(t, 2, s.cfg.ForkChoiceStore.NodeCount())
 }
@@ -265,10 +264,10 @@ func TestService_ReceiveBlockBatch(t *testing.T) {
 				block: genFullBlock(t, util.DefaultBlockGenConfig(), 1 /*slot*/),
 			},
 			check: func(t *testing.T, s *Service) {
-				time.Sleep(100 * time.Millisecond)
-				if recvd := len(s.cfg.StateNotifier.(*blockchainTesting.MockStateNotifier).ReceivedEvents()); recvd < 1 {
-					t.Errorf("Received %d state notifications, expected at least 1", recvd)
-				}
+				notifier := s.cfg.StateNotifier.(*blockchainTesting.MockStateNotifier)
+				require.Eventually(t, func() bool {
+					return len(notifier.ReceivedEvents()) >= 1
+				}, 2*time.Second, 10*time.Millisecond, "Expected at least 1 state notification")
 			},
 		},
 	}
@@ -512,8 +511,9 @@ func Test_executePostFinalizationTasks(t *testing.T) {
 		s.cfg.StateNotifier = notifier
 		s.executePostFinalizationTasks(s.ctx, headState)

-		time.Sleep(1 * time.Second) // sleep for a second because event is in a separate go routine
-		require.Equal(t, 1, len(notifier.ReceivedEvents()))
+		require.Eventually(t, func() bool {
+			return len(notifier.ReceivedEvents()) == 1
+		}, 5*time.Second, 50*time.Millisecond, "Expected exactly 1 state notification")
 		e := notifier.ReceivedEvents()[0]
 		assert.Equal(t, statefeed.FinalizedCheckpoint, int(e.Type))
 		fc, ok := e.Data.(*ethpbv1.EventFinalizedCheckpoint)
@@ -552,8 +552,9 @@ func Test_executePostFinalizationTasks(t *testing.T) {
 		s.cfg.StateNotifier = notifier
 		s.executePostFinalizationTasks(s.ctx, headState)

-		time.Sleep(1 * time.Second) // sleep for a second because event is in a separate go routine
-		require.Equal(t, 1, len(notifier.ReceivedEvents()))
+		require.Eventually(t, func() bool {
+			return len(notifier.ReceivedEvents()) == 1
+		}, 5*time.Second, 50*time.Millisecond, "Expected exactly 1 state notification")
 		e := notifier.ReceivedEvents()[0]
 		assert.Equal(t, statefeed.FinalizedCheckpoint, int(e.Type))
 		fc, ok := e.Data.(*ethpbv1.EventFinalizedCheckpoint)
@@ -596,13 +597,13 @@ func TestProcessLightClientBootstrap(t *testing.T) {

 			s.executePostFinalizationTasks(s.ctx, l.AttestedState)

-			// wait for the goroutine to finish processing
-			time.Sleep(1 * time.Second)
-
-			// Check that the light client bootstrap is saved
-			b, err := s.lcStore.LightClientBootstrap(ctx, [32]byte(cp.Root))
-			require.NoError(t, err)
-			require.NotNil(t, b)
+			// Wait for the light client bootstrap to be saved (runs in goroutine)
+			var b interfaces.LightClientBootstrap
+			require.Eventually(t, func() bool {
+				var err error
+				b, err = s.lcStore.LightClientBootstrap(ctx, [32]byte(cp.Root))
+				return err == nil && b != nil
+			}, 5*time.Second, 50*time.Millisecond, "Light client bootstrap was not saved within timeout")

 			btst, err := lightClient.NewLightClientBootstrapFromBeaconState(ctx, l.FinalizedState.Slot(), l.FinalizedState, l.FinalizedBlock)
 			require.NoError(t, err)
--- a/beacon-chain/light-client/store_test.go
+++ b/beacon-chain/light-client/store_test.go
@@ -75,7 +75,6 @@ func TestLightClientStore_SetLastFinalityUpdate(t *testing.T) {
 	p2p := p2pTesting.NewTestP2P(t)
 	lcStore := NewLightClientStore(p2p, new(event.Feed), testDB.SetupDB(t))

-	timeForGoroutinesToFinish := 20 * time.Microsecond
 	// update 0 with basic data and no supermajority following an empty lastFinalityUpdate - should save and broadcast
 	l0 := util.NewTestLightClient(t, version.Altair)
 	update0, err := NewLightClientFinalityUpdateFromBeaconState(l0.Ctx, l0.State, l0.Block, l0.AttestedState, l0.AttestedBlock, l0.FinalizedBlock)
@@ -87,8 +86,9 @@ func TestLightClientStore_SetLastFinalityUpdate(t *testing.T) {

 	lcStore.SetLastFinalityUpdate(update0, true)
 	require.Equal(t, update0, lcStore.LastFinalityUpdate(), "lastFinalityUpdate should match the set value")
-	time.Sleep(timeForGoroutinesToFinish) // give some time for the broadcast goroutine to finish
-	require.Equal(t, true, p2p.BroadcastCalled.Load(), "Broadcast should have been called after setting a new last finality update when previous is nil")
+	require.Eventually(t, func() bool {
+		return p2p.BroadcastCalled.Load()
+	}, time.Second, 10*time.Millisecond, "Broadcast should have been called after setting a new last finality update when previous is nil")
 	p2p.BroadcastCalled.Store(false) // Reset for next test

 	// update 1 with same finality slot, increased attested slot, and no supermajority - should save but not broadcast
@@ -102,7 +102,7 @@ func TestLightClientStore_SetLastFinalityUpdate(t *testing.T) {

 	lcStore.SetLastFinalityUpdate(update1, true)
 	require.Equal(t, update1, lcStore.LastFinalityUpdate(), "lastFinalityUpdate should match the set value")
-	time.Sleep(timeForGoroutinesToFinish) // give some time for the broadcast goroutine to finish
+	time.Sleep(50 * time.Millisecond) // Wait briefly to verify broadcast is not called
 	require.Equal(t, false, p2p.BroadcastCalled.Load(), "Broadcast should not have been called after setting a new last finality update without supermajority")
 	p2p.BroadcastCalled.Store(false) // Reset for next test

@@ -117,8 +117,9 @@ func TestLightClientStore_SetLastFinalityUpdate(t *testing.T) {

 	lcStore.SetLastFinalityUpdate(update2, true)
 	require.Equal(t, update2, lcStore.LastFinalityUpdate(), "lastFinalityUpdate should match the set value")
-	time.Sleep(timeForGoroutinesToFinish) // give some time for the broadcast goroutine to finish
-	require.Equal(t, true, p2p.BroadcastCalled.Load(), "Broadcast should have been called after setting a new last finality update with supermajority")
+	require.Eventually(t, func() bool {
+		return p2p.BroadcastCalled.Load()
+	}, time.Second, 10*time.Millisecond, "Broadcast should have been called after setting a new last finality update with supermajority")
 	p2p.BroadcastCalled.Store(false) // Reset for next test

 	// update 3 with same finality slot, increased attested slot, and supermajority - should save but not broadcast
@@ -132,7 +133,7 @@ func TestLightClientStore_SetLastFinalityUpdate(t *testing.T) {

 	lcStore.SetLastFinalityUpdate(update3, true)
 	require.Equal(t, update3, lcStore.LastFinalityUpdate(), "lastFinalityUpdate should match the set value")
-	time.Sleep(timeForGoroutinesToFinish) // give some time for the broadcast goroutine to finish
+	time.Sleep(50 * time.Millisecond) // Wait briefly to verify broadcast is not called
 	require.Equal(t, false, p2p.BroadcastCalled.Load(), "Broadcast should not have been when previous was already broadcast")

 	// update 4 with increased finality slot, increased attested slot, and supermajority - should save and broadcast
@@ -146,8 +147,9 @@ func TestLightClientStore_SetLastFinalityUpdate(t *testing.T) {

 	lcStore.SetLastFinalityUpdate(update4, true)
 	require.Equal(t, update4, lcStore.LastFinalityUpdate(), "lastFinalityUpdate should match the set value")
-	time.Sleep(timeForGoroutinesToFinish) // give some time for the broadcast goroutine to finish
-	require.Equal(t, true, p2p.BroadcastCalled.Load(), "Broadcast should have been called after a new finality update with increased finality slot")
+	require.Eventually(t, func() bool {
+		return p2p.BroadcastCalled.Load()
+	}, time.Second, 10*time.Millisecond, "Broadcast should have been called after a new finality update with increased finality slot")
 	p2p.BroadcastCalled.Store(false) // Reset for next test

 	// update 5 with the same new finality slot, increased attested slot, and supermajority - should save but not broadcast
@@ -161,7 +163,7 @@ func TestLightClientStore_SetLastFinalityUpdate(t *testing.T) {

 	lcStore.SetLastFinalityUpdate(update5, true)
 	require.Equal(t, update5, lcStore.LastFinalityUpdate(), "lastFinalityUpdate should match the set value")
-	time.Sleep(timeForGoroutinesToFinish) // give some time for the broadcast goroutine to finish
+	time.Sleep(50 * time.Millisecond) // Wait briefly to verify broadcast is not called
 	require.Equal(t, false, p2p.BroadcastCalled.Load(), "Broadcast should not have been called when previous was already broadcast with supermajority")

 	// update 6 with the same new finality slot, increased attested slot, and no supermajority - should save but not broadcast
@@ -175,7 +177,7 @@ func TestLightClientStore_SetLastFinalityUpdate(t *testing.T) {

 	lcStore.SetLastFinalityUpdate(update6, true)
 	require.Equal(t, update6, lcStore.LastFinalityUpdate(), "lastFinalityUpdate should match the set value")
-	time.Sleep(timeForGoroutinesToFinish) // give some time for the broadcast goroutine to finish
+	time.Sleep(50 * time.Millisecond) // Wait briefly to verify broadcast is not called
 	require.Equal(t, false, p2p.BroadcastCalled.Load(), "Broadcast should not have been called when previous was already broadcast with supermajority")
 }

--- a/beacon-chain/p2p/broadcaster_test.go
+++ b/beacon-chain/p2p/broadcaster_test.go
@@ -72,7 +72,10 @@ func TestService_Broadcast(t *testing.T) {
 	sub, err := p2.SubscribeToTopic(topic)
 	require.NoError(t, err)

-	time.Sleep(50 * time.Millisecond) // libp2p fails without this delay...
+	// Wait for libp2p mesh to establish
+	require.Eventually(t, func() bool {
+		return len(p.pubsub.ListPeers(topic)) > 0
+	}, 5*time.Second, 10*time.Millisecond, "libp2p mesh did not establish")

 	// Async listen for the pubsub, must be before the broadcast.
 	var wg sync.WaitGroup
@@ -186,7 +189,10 @@ func TestService_BroadcastAttestation(t *testing.T) {
 	sub, err := p2.SubscribeToTopic(topic)
 	require.NoError(t, err)

-	time.Sleep(50 * time.Millisecond) // libp2p fails without this delay...
+	// Wait for libp2p mesh to establish
+	require.Eventually(t, func() bool {
+		return len(p.pubsub.ListPeers(topic)) > 0
+	}, 5*time.Second, 10*time.Millisecond, "libp2p mesh did not establish")

 	// Async listen for the pubsub, must be before the broadcast.
 	var wg sync.WaitGroup
@@ -375,7 +381,15 @@ func TestService_BroadcastAttestationWithDiscoveryAttempts(t *testing.T) {
 	_, err = tpHandle.Subscribe()
 	require.NoError(t, err)

-	time.Sleep(500 * time.Millisecond) // libp2p fails without this delay...
+	// This test specifically tests discovery-based peer finding, which requires
+	// time for nodes to discover each other. Using a fixed sleep here is intentional
+	// as we're testing the discovery timing behavior.
+	time.Sleep(500 * time.Millisecond)
+
+	// Verify mesh establishment after discovery
+	require.Eventually(t, func() bool {
+		return len(p.pubsub.ListPeers(topic)) > 0 && len(p2.pubsub.ListPeers(topic)) > 0
+	}, 5*time.Second, 10*time.Millisecond, "libp2p mesh did not establish")

 	nodePeers := p.pubsub.ListPeers(topic)
 	nodePeers2 := p2.pubsub.ListPeers(topic)
@@ -444,7 +458,10 @@ func TestService_BroadcastSyncCommittee(t *testing.T) {
 	sub, err := p2.SubscribeToTopic(topic)
 	require.NoError(t, err)

-	time.Sleep(50 * time.Millisecond) // libp2p fails without this delay...
+	// Wait for libp2p mesh to establish
+	require.Eventually(t, func() bool {
+		return len(p.pubsub.ListPeers(topic)) > 0
+	}, 5*time.Second, 10*time.Millisecond, "libp2p mesh did not establish")

 	// Async listen for the pubsub, must be before the broadcast.
 	var wg sync.WaitGroup
@@ -521,7 +538,10 @@ func TestService_BroadcastBlob(t *testing.T) {
 	sub, err := p2.SubscribeToTopic(topic)
 	require.NoError(t, err)

-	time.Sleep(50 * time.Millisecond) // libp2p fails without this delay...
+	// Wait for libp2p mesh to establish
+	require.Eventually(t, func() bool {
+		return len(p.pubsub.ListPeers(topic)) > 0
+	}, 5*time.Second, 10*time.Millisecond, "libp2p mesh did not establish")

 	// Async listen for the pubsub, must be before the broadcast.
 	var wg sync.WaitGroup
@@ -584,7 +604,10 @@ func TestService_BroadcastLightClientOptimisticUpdate(t *testing.T) {
 	sub, err := p2.SubscribeToTopic(topic)
 	require.NoError(t, err)

-	time.Sleep(50 * time.Millisecond) // libp2p fails without this delay...
+	// Wait for libp2p mesh to establish
+	require.Eventually(t, func() bool {
+		return len(p.pubsub.ListPeers(topic)) > 0
+	}, 5*time.Second, 10*time.Millisecond, "libp2p mesh did not establish")

 	// Async listen for the pubsub, must be before the broadcast.
 	var wg sync.WaitGroup
@@ -660,7 +683,10 @@ func TestService_BroadcastLightClientFinalityUpdate(t *testing.T) {
 	sub, err := p2.SubscribeToTopic(topic)
 	require.NoError(t, err)

-	time.Sleep(50 * time.Millisecond) // libp2p fails without this delay...
+	// Wait for libp2p mesh to establish
+	require.Eventually(t, func() bool {
+		return len(p.pubsub.ListPeers(topic)) > 0
+	}, 5*time.Second, 10*time.Millisecond, "libp2p mesh did not establish")

 	// Async listen for the pubsub, must be before the broadcast.
 	var wg sync.WaitGroup
@@ -771,8 +797,10 @@ func TestService_BroadcastDataColumn(t *testing.T) {
 	sub, err := p2.SubscribeToTopic(topic)
 	require.NoError(t, err)

-	// libp2p fails without this delay
-	time.Sleep(50 * time.Millisecond)
+	// Wait for libp2p mesh to establish
+	require.Eventually(t, func() bool {
+		return len(service.pubsub.ListPeers(topic)) > 0
+	}, 5*time.Second, 10*time.Millisecond, "libp2p mesh did not establish")

 	// Broadcast to peers and wait.
 	err = service.BroadcastDataColumnSidecars(ctx, []blocks.VerifiedRODataColumn{verifiedRoSidecar})
--- a/beacon-chain/p2p/discovery_test.go
+++ b/beacon-chain/p2p/discovery_test.go
@@ -482,12 +482,12 @@ func TestStaticPeering_PeersAreAdded(t *testing.T) {
 		s.Start()
 		<-exitRoutine
 	}()
-	time.Sleep(50 * time.Millisecond)
+	time.Sleep(50 * time.Millisecond) // Wait for service initialization
 	var vr [32]byte
 	require.NoError(t, cs.SetClock(startup.NewClock(time.Now(), vr)))
-	time.Sleep(4 * time.Second)
-	ps := s.host.Network().Peers()
-	assert.Equal(t, 5, len(ps), "Not all peers added to peerstore")
+	require.Eventually(t, func() bool {
+		return len(s.host.Network().Peers()) == 5
+	}, 10*time.Second, 100*time.Millisecond, "Not all peers added to peerstore")
 	require.NoError(t, s.Stop())
 	exitRoutine <- true
 }
--- a/beacon-chain/p2p/service_test.go
+++ b/beacon-chain/p2p/service_test.go
@@ -80,8 +80,9 @@ func TestService_Start_OnlyStartsOnce(t *testing.T) {
 	}()
 	var vr [32]byte
 	require.NoError(t, cs.SetClock(startup.NewClock(time.Now(), vr)))
-	time.Sleep(time.Second * 2)
-	assert.Equal(t, true, s.started, "Expected service to be started")
+	require.Eventually(t, func() bool {
+		return s.started
+	}, 5*time.Second, 100*time.Millisecond, "Expected service to be started")
 	s.Start()
 	require.LogsContain(t, hook, "Attempted to start p2p service when it was already started")
 	require.NoError(t, s.Stop())
@@ -260,17 +261,9 @@ func TestListenForNewNodes(t *testing.T) {
 	err = cs.SetClock(startup.NewClock(genesisTime, gvr))
 	require.NoError(t, err, "Could not set clock in service")

-	actualPeerCount := len(s.host.Network().Peers())
-	for range 40 {
-		if actualPeerCount == peerCount {
-			break
-		}
-
-		time.Sleep(100 * time.Millisecond)
-		actualPeerCount = len(s.host.Network().Peers())
-	}
-
-	assert.Equal(t, peerCount, actualPeerCount, "Not all peers added to peerstore")
+	require.Eventually(t, func() bool {
+		return len(s.host.Network().Peers()) == peerCount
+	}, 5*time.Second, 100*time.Millisecond, "Not all peers added to peerstore")

 	err = s.Stop()
 	require.NoError(t, err, "Failed to stop service")
--- a/beacon-chain/rpc/eth/beacon/handlers_pool_test.go
+++ b/beacon-chain/rpc/eth/beacon/handlers_pool_test.go
@@ -657,8 +657,9 @@ func TestSubmitAttestationsV2(t *testing.T) {
 			assert.Equal(t, primitives.Epoch(0), broadcaster.BroadcastAttestations[0].GetData().Source.Epoch)
 			assert.Equal(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", hexutil.Encode(broadcaster.BroadcastAttestations[0].GetData().Target.Root))
 			assert.Equal(t, primitives.Epoch(0), broadcaster.BroadcastAttestations[0].GetData().Target.Epoch)
-			time.Sleep(100 * time.Millisecond) // Wait for async pool save
-			assert.Equal(t, 1, s.AttestationsPool.UnaggregatedAttestationCount())
+			require.Eventually(t, func() bool {
+				return s.AttestationsPool.UnaggregatedAttestationCount() == 1
+			}, time.Second, 10*time.Millisecond, "Expected 1 attestation in pool")
 		})
 		t.Run("multiple", func(t *testing.T) {
 			broadcaster := &p2pMock.MockBroadcaster{}
@@ -677,8 +678,9 @@ func TestSubmitAttestationsV2(t *testing.T) {
 			assert.Equal(t, http.StatusOK, writer.Code)
 			assert.Equal(t, true, broadcaster.BroadcastCalled.Load())
 			assert.Equal(t, 2, broadcaster.NumAttestations())
-			time.Sleep(100 * time.Millisecond) // Wait for async pool save
-			assert.Equal(t, 2, s.AttestationsPool.UnaggregatedAttestationCount())
+			require.Eventually(t, func() bool {
+				return s.AttestationsPool.UnaggregatedAttestationCount() == 2
+			}, time.Second, 10*time.Millisecond, "Expected 2 attestations in pool")
 		})
 		t.Run("phase0 att post electra", func(t *testing.T) {
 			params.SetupTestConfigCleanup(t)
@@ -798,8 +800,9 @@ func TestSubmitAttestationsV2(t *testing.T) {
 			assert.Equal(t, primitives.Epoch(0), broadcaster.BroadcastAttestations[0].GetData().Source.Epoch)
 			assert.Equal(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", hexutil.Encode(broadcaster.BroadcastAttestations[0].GetData().Target.Root))
 			assert.Equal(t, primitives.Epoch(0), broadcaster.BroadcastAttestations[0].GetData().Target.Epoch)
-			time.Sleep(100 * time.Millisecond) // Wait for async pool save
-			assert.Equal(t, 1, s.AttestationsPool.UnaggregatedAttestationCount())
+			require.Eventually(t, func() bool {
+				return s.AttestationsPool.UnaggregatedAttestationCount() == 1
+			}, time.Second, 10*time.Millisecond, "Expected 1 attestation in pool")
 		})
 		t.Run("multiple", func(t *testing.T) {
 			broadcaster := &p2pMock.MockBroadcaster{}
@@ -818,8 +821,9 @@ func TestSubmitAttestationsV2(t *testing.T) {
 			assert.Equal(t, http.StatusOK, writer.Code)
 			assert.Equal(t, true, broadcaster.BroadcastCalled.Load())
 			assert.Equal(t, 2, broadcaster.NumAttestations())
-			time.Sleep(100 * time.Millisecond) // Wait for async pool save
-			assert.Equal(t, 2, s.AttestationsPool.UnaggregatedAttestationCount())
+			require.Eventually(t, func() bool {
+				return s.AttestationsPool.UnaggregatedAttestationCount() == 2
+			}, time.Second, 10*time.Millisecond, "Expected 2 attestations in pool")
 		})
 		t.Run("no body", func(t *testing.T) {
 			request := httptest.NewRequest(http.MethodPost, "http://example.com", nil)
@@ -1375,9 +1379,9 @@ func TestSubmitSignedBLSToExecutionChanges_Ok(t *testing.T) {
 	writer.Body = &bytes.Buffer{}
 	s.SubmitBLSToExecutionChanges(writer, request)
 	assert.Equal(t, http.StatusOK, writer.Code)
-	time.Sleep(100 * time.Millisecond) // Delay to let the routine start
-	assert.Equal(t, true, broadcaster.BroadcastCalled.Load())
-	assert.Equal(t, numValidators, len(broadcaster.BroadcastMessages))
+	require.Eventually(t, func() bool {
+		return broadcaster.BroadcastCalled.Load() && len(broadcaster.BroadcastMessages) == numValidators
+	}, time.Second, 10*time.Millisecond, "Broadcast should be called with all messages")

 	poolChanges, err := s.BLSChangesPool.PendingBLSToExecChanges()
 	require.Equal(t, len(poolChanges), len(signedChanges))
@@ -1591,10 +1595,10 @@ func TestSubmitSignedBLSToExecutionChanges_Failures(t *testing.T) {

 	s.SubmitBLSToExecutionChanges(writer, request)
 	assert.Equal(t, http.StatusBadRequest, writer.Code)
-	time.Sleep(10 * time.Millisecond) // Delay to allow the routine to start
 	require.StringContains(t, "One or more messages failed validation", writer.Body.String())
-	assert.Equal(t, true, broadcaster.BroadcastCalled.Load())
-	assert.Equal(t, numValidators, len(broadcaster.BroadcastMessages)+1)
+	require.Eventually(t, func() bool {
+		return broadcaster.BroadcastCalled.Load() && len(broadcaster.BroadcastMessages)+1 == numValidators
+	}, time.Second, 10*time.Millisecond, "Broadcast should be called with expected messages")

 	poolChanges, err := s.BLSChangesPool.PendingBLSToExecChanges()
 	require.Equal(t, len(poolChanges)+1, len(signedChanges))
--- a/beacon-chain/sync/service_test.go
+++ b/beacon-chain/sync/service_test.go
@@ -70,7 +70,6 @@ func TestSyncHandlers_WaitToSync(t *testing.T) {

 	topic := "/eth2/%x/beacon_block"
 	go r.startDiscoveryAndSubscriptions()
-	time.Sleep(100 * time.Millisecond)

 	var vr [32]byte
 	require.NoError(t, gs.SetClock(startup.NewClock(time.Now(), vr)))
@@ -83,9 +82,11 @@ func TestSyncHandlers_WaitToSync(t *testing.T) {
 	msg.Block.ParentRoot = util.Random32Bytes(t)
 	msg.Signature = sk.Sign([]byte("data")).Marshal()
 	p2p.ReceivePubSub(topic, msg)
-	// wait for chainstart to be sent
-	time.Sleep(400 * time.Millisecond)
-	require.Equal(t, true, r.chainStarted.IsSet(), "Did not receive chain start event.")
+
+	// Wait for chainstart event to be processed
+	require.Eventually(t, func() bool {
+		return r.chainStarted.IsSet()
+	}, 5*time.Second, 50*time.Millisecond, "Did not receive chain start event.")
 }

 func TestSyncHandlers_WaitForChainStart(t *testing.T) {
@@ -217,20 +218,18 @@ func TestSyncService_StopCleanly(t *testing.T) {
 	p2p.Digest, err = r.currentForkDigest()
 	require.NoError(t, err)

-	// wait for chainstart to be sent
-	time.Sleep(2 * time.Second)
-	require.Equal(t, true, r.chainStarted.IsSet(), "Did not receive chain start event.")
-
-	require.NotEqual(t, 0, len(r.cfg.p2p.PubSub().GetTopics()))
-	require.NotEqual(t, 0, len(r.cfg.p2p.Host().Mux().Protocols()))
+	// Wait for chainstart and topics to be registered
+	require.Eventually(t, func() bool {
+		return r.chainStarted.IsSet() && len(r.cfg.p2p.PubSub().GetTopics()) > 0 && len(r.cfg.p2p.Host().Mux().Protocols()) > 0
+	}, 5*time.Second, 50*time.Millisecond, "Did not receive chain start event or topics not registered.")

 	// Both pubsub and rpc topics should be unsubscribed.
 	require.NoError(t, r.Stop())

-	// Sleep to allow pubsub topics to be deregistered.
-	time.Sleep(1 * time.Second)
-	require.Equal(t, 0, len(r.cfg.p2p.PubSub().GetTopics()))
-	require.Equal(t, 0, len(r.cfg.p2p.Host().Mux().Protocols()))
+	// Wait for pubsub topics to be deregistered.
+	require.Eventually(t, func() bool {
+		return len(r.cfg.p2p.PubSub().GetTopics()) == 0 && len(r.cfg.p2p.Host().Mux().Protocols()) == 0
+	}, 5*time.Second, 50*time.Millisecond, "Pubsub topics were not deregistered")
 }

 func TestService_Stop_SendsGoodbyeMessages(t *testing.T) {
--- a/beacon-chain/sync/validate_aggregate_proof_test.go
+++ b/beacon-chain/sync/validate_aggregate_proof_test.go
@@ -614,11 +614,10 @@ func TestVerifyIndexInCommittee_SeenAggregatorEpoch(t *testing.T) {
 		},
 	}

-	time.Sleep(10 * time.Millisecond) // Wait for cached value to pass through buffers.
-	if res, err := r.validateAggregateAndProof(t.Context(), "", msg); res == pubsub.ValidationAccept {
-		_ = err
-		t.Fatal("Validated status is true")
-	}
+	require.Eventually(t, func() bool {
+		res, _ := r.validateAggregateAndProof(t.Context(), "", msg)
+		return res != pubsub.ValidationAccept
+	}, time.Second, 10*time.Millisecond, "Expected validation to reject duplicate aggregate")
 }

 func TestValidateAggregateAndProof_BadBlock(t *testing.T) {
--- a/beacon-chain/sync/validate_beacon_blocks_test.go
+++ b/beacon-chain/sync/validate_beacon_blocks_test.go
@@ -992,7 +992,6 @@ func TestValidateBeaconBlockPubSub_SeenProposerSlot(t *testing.T) {

 	// Mark the proposer/slot as seen
 	r.setSeenBlockIndexSlot(msg.Block.Slot, msg.Block.ProposerIndex)
-	time.Sleep(10 * time.Millisecond) // Wait for cached value to pass through buffers

 	// Prepare and validate the second message (clone)
 	buf := new(bytes.Buffer)
@@ -1010,9 +1009,11 @@ func TestValidateBeaconBlockPubSub_SeenProposerSlot(t *testing.T) {
 	}

 	// Since this is not an equivocation (same signature), it should be ignored
-	res, err := r.validateBeaconBlockPubSub(ctx, "", m)
-	assert.NoError(t, err)
-	assert.Equal(t, pubsub.ValidationIgnore, res, "block with same signature should be ignored")
+	// Wait for the cached value to propagate through buffers
+	require.Eventually(t, func() bool {
+		res, err := r.validateBeaconBlockPubSub(ctx, "", m)
+		return err == nil && res == pubsub.ValidationIgnore
+	}, time.Second, 10*time.Millisecond, "block with same signature should be ignored")

 	// Verify no slashings were created
 	assert.Equal(t, 0, len(slashingPool.PendingPropSlashings), "Expected no slashings for same signature")
--- a/changelog/pvl_fix-flaky-tests-polling.md
+++ b/changelog/pvl_fix-flaky-tests-polling.md
@@ -0,0 +1,3 @@
+### Changed
+
+- Replaced `time.Sleep` with `require.Eventually` polling in tests to fix flaky behavior caused by race conditions between goroutines and assertions.
--- a/testing/assertions/assertions.go
+++ b/testing/assertions/assertions.go
@@ -8,6 +8,7 @@ import (
 	"runtime"
 	"sort"
 	"strings"
+	"time"

 	"github.com/OffchainLabs/prysm/v7/encoding/ssz/equality"
 	"github.com/d4l3k/messagediff"
@@ -138,12 +139,21 @@ func StringContains(loggerFn assertionLoggerFn, expected, actual string, flag bo

 // NoError asserts that error is nil.
 func NoError(loggerFn assertionLoggerFn, err error, msg ...any) {
-	// reflect.ValueOf is needed for nil instances of custom types implementing Error
-	if err != nil && !reflect.ValueOf(err).IsNil() {
-		errMsg := parseMsg("Unexpected error", msg...)
-		_, file, line, _ := runtime.Caller(2)
-		loggerFn("%s:%d %s: %v", filepath.Base(file), line, errMsg, err)
+	if err == nil {
+		return
 	}
+	// reflect.ValueOf is needed for nil instances of custom types implementing Error.
+	// Only check IsNil for types that support it to avoid panics on struct types.
+	v := reflect.ValueOf(err)
+	switch v.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice, reflect.UnsafePointer:
+		if v.IsNil() {
+			return
+		}
+	}
+	errMsg := parseMsg("Unexpected error", msg...)
+	_, file, line, _ := runtime.Caller(2)
+	loggerFn("%s:%d %s: %v", filepath.Base(file), line, errMsg, err)
 }

 // ErrorIs uses Errors.Is to recursively unwrap err looking for target in the chain.
@@ -341,3 +351,18 @@ func (tb *TBMock) Errorf(format string, args ...any) {
 func (tb *TBMock) Fatalf(format string, args ...any) {
 	tb.FatalfMsg = fmt.Sprintf(format, args...)
 }
+
+// Eventually asserts that given condition will be met within waitFor time,
+// periodically checking target function each tick.
+func Eventually(loggerFn assertionLoggerFn, condition func() bool, waitFor, tick time.Duration, msg ...any) {
+	deadline := time.Now().Add(waitFor)
+	for time.Now().Before(deadline) {
+		if condition() {
+			return
+		}
+		time.Sleep(tick)
+	}
+	errMsg := parseMsg("Condition never satisfied", msg...)
+	_, file, line, _ := runtime.Caller(2)
+	loggerFn("%s:%d %s (waited %v)", filepath.Base(file), line, errMsg, waitFor)
+}
--- a/testing/require/requires.go
+++ b/testing/require/requires.go
@@ -1,6 +1,8 @@
 package require

 import (
+	"time"
+
 	"github.com/OffchainLabs/prysm/v7/testing/assertions"
 	"github.com/sirupsen/logrus/hooks/test"
 )
@@ -87,3 +89,9 @@ func ErrorIs(tb assertions.AssertionTestingTB, err, target error, msg ...any) {
 func StringContains(tb assertions.AssertionTestingTB, expected, actual string, msg ...any) {
 	assertions.StringContains(tb.Fatalf, expected, actual, true, msg)
 }
+
+// Eventually asserts that given condition will be met within waitFor time,
+// periodically checking target function each tick.
+func Eventually(tb assertions.AssertionTestingTB, condition func() bool, waitFor, tick time.Duration, msg ...any) {
+	assertions.Eventually(tb.Fatalf, condition, waitFor, tick, msg...)
+}