fix(redis): default sentinel ports per address

changelog/haoshengzhen-redis-sentinel-default-port.md

@@ -0,0 +1,2 @@
+### Fixed
+- Default missing Redis Sentinel ports per address when parsing `redis+sentinel` URLs.

util/redisutil/redisutil.go

@@ -96,7 +96,7 @@ func getAddressesWithDefaults(u *url.URL) []string {
 	for _, urlHost := range urlHosts {
 		host, port, err := net.SplitHostPort(urlHost)
 		if err != nil {
-			host = u.Host
+			host = strings.TrimPrefix(strings.TrimSuffix(urlHost, "]"), "[")
 		}
 		if host == "" {
 			host = "localhost"

util/redisutil/redisutil_test.go

@@ -0,0 +1,21 @@
+// Copyright 2021-2026, Offchain Labs, Inc.
+// For license information, see https://github.com/OffchainLabs/nitro/blob/master/LICENSE.md
+
+package redisutil
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestParseFailoverRedisUrlDefaultsPortPerAddress(t *testing.T) {
+	options, err := parseFailoverRedisUrl("redis+sentinel://sentinel-1,sentinel-2:26379/master")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	want := []string{"sentinel-1:6379", "sentinel-2:26379"}
+	if !reflect.DeepEqual(options.SentinelAddrs, want) {
+		t.Fatalf("unexpected sentinel addrs: have %v, want %v", options.SentinelAddrs, want)
+	}
+}