From e9acf48a25feb9719a795f49977f5e667ba07ded Mon Sep 17 00:00:00 2001
From: Daniel Liu <139250065@qq.com>
Date: Fri, 15 May 2026 23:46:52 +0800
Subject: [PATCH] test(eth): stabilize fast sync disabling test

Replace the fixed sleep and one-shot synchronise call with a timeout-based retry loop so the test tolerates CI scheduling variance. Add protocol manager cleanup to avoid leaking background work between test runs.
---
 eth/sync_test.go | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/eth/sync_test.go b/eth/sync_test.go
index 8c25a98190b4..06d2c69a6364 100644
--- a/eth/sync_test.go
+++ b/eth/sync_test.go
@@ -31,11 +31,13 @@ import (
 func TestFastSyncDisabling(t *testing.T) {
 	// Create a pristine protocol manager, check that fast sync is left enabled
 	pmEmpty, _ := newTestProtocolManagerMust(t, downloader.FastSync, 0, nil, nil)
+	defer pmEmpty.Stop()
 	if atomic.LoadUint32(&pmEmpty.snapSync) == 0 {
 		t.Fatalf("snap sync disabled on pristine blockchain")
 	}
 	// Create a full protocol manager, check that snap sync gets disabled
 	pmFull, _ := newTestProtocolManagerMust(t, downloader.FastSync, 1024, nil, nil)
+	defer pmFull.Stop()
 	if atomic.LoadUint32(&pmFull.snapSync) == 1 {
 		t.Fatalf("snap sync not disabled on non-empty blockchain")
 	}
@@ -45,11 +47,19 @@ func TestFastSyncDisabling(t *testing.T) {
 	go pmFull.handle(pmFull.newPeer(63, p2p.NewPeer(enode.ID{}, "empty", nil), io2))
 	go pmEmpty.handle(pmEmpty.newPeer(63, p2p.NewPeer(enode.ID{}, "full", nil), io1))
 
-	time.Sleep(250 * time.Millisecond)
-	pmEmpty.synchronise(pmEmpty.peers.BestPeer())
+	deadline := time.After(15 * time.Second)
+	ticker := time.NewTicker(100 * time.Millisecond)
+	defer ticker.Stop()
 
-	// Check that snap sync was disabled
-	if atomic.LoadUint32(&pmEmpty.snapSync) == 1 {
-		t.Fatalf("snap sync not disabled after successful synchronisation")
+	for {
+		if atomic.LoadUint32(&pmEmpty.snapSync) == 0 {
+			return
+		}
+		select {
+		case <-deadline:
+			t.Fatalf("snap sync not disabled after successful synchronisation")
+		case <-ticker.C:
+			pmEmpty.synchronise(pmEmpty.peers.BestPeer())
+		}
 	}
 }