From 7d463aedd3ad1a88964a4286f443c712164543ec Mon Sep 17 00:00:00 2001
From: Daniel Liu <139250065@qq.com>
Date: Mon, 13 Apr 2026 20:10:56 +0800
Subject: [PATCH] accounts/keystore: fix flaky TestUpdatedKeyfileContents
 (#34084)

TestUpdatedKeyfileContents was intermittently failing with:

- Emptying account file failed
- wasn't notified of new accounts

Root cause: waitForAccounts required the account list match and an
immediately readable ks.changes notification in the same instant,
creating a timing race between cache update visibility and channel
delivery.

This change keeps the same timeout window but waits until both
conditions are observed, which preserves test intent while removing the
flaky timing dependency.

Validation:
- go test ./accounts/keystore -run '^TestUpdatedKeyfileContents$'
-count=100
---
 accounts/keystore/account_cache_test.go | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/accounts/keystore/account_cache_test.go b/accounts/keystore/account_cache_test.go
index c9a8cdfcef..e49b110e7e 100644
--- a/accounts/keystore/account_cache_test.go
+++ b/accounts/keystore/account_cache_test.go
@@ -68,18 +68,27 @@ func waitWatcherStart(ks *KeyStore) bool {
 
 func waitForAccounts(wantAccounts []accounts.Account, ks *KeyStore) error {
 	var list []accounts.Account
+	haveAccounts := false
+	haveChange := false
 	for t0 := time.Now(); time.Since(t0) < 5*time.Second; time.Sleep(100 * time.Millisecond) {
-		list = ks.Accounts()
-		if reflect.DeepEqual(list, wantAccounts) {
-			// ks should have also received change notifications
+		if !haveAccounts {
+			list = ks.Accounts()
+			haveAccounts = reflect.DeepEqual(list, wantAccounts)
+		}
+		if !haveChange {
 			select {
 			case <-ks.changes:
+				haveChange = true
 			default:
-				return errors.New("wasn't notified of new accounts")
 			}
+		}
+		if haveAccounts && haveChange {
 			return nil
 		}
 	}
+	if haveAccounts {
+		return errors.New("wasn't notified of new accounts")
+	}
 	return fmt.Errorf("\ngot  %v\nwant %v", list, wantAccounts)
 }