From 7e55ff3458f77f9b434f7bcfda4c66a06d3c0ced Mon Sep 17 00:00:00 2001
From: "R.B. Boyer" <rb@hashicorp.com>
Date: Thu, 31 Oct 2024 16:19:53 -0500
Subject: [PATCH] move out of package

---
 agent/consul/state/catalog.go       | 15 ++-------------
 lib/stringslice/stringslice.go      | 14 ++++++++++++++
 lib/stringslice/stringslice_test.go | 25 +++++++++++++++++++++++++
 3 files changed, 41 insertions(+), 13 deletions(-)

diff --git a/agent/consul/state/catalog.go b/agent/consul/state/catalog.go
index 2c92d7d58d..b8588f17cc 100644
--- a/agent/consul/state/catalog.go
+++ b/agent/consul/state/catalog.go
@@ -20,6 +20,7 @@ import (
 	"github.com/hashicorp/consul/api"
 	"github.com/hashicorp/consul/lib"
 	"github.com/hashicorp/consul/lib/maps"
+	"github.com/hashicorp/consul/lib/stringslice"
 	"github.com/hashicorp/consul/types"
 )
 
@@ -1169,7 +1170,7 @@ func (s *Store) AssignManualServiceVIPs(idx uint64, psn structs.PeeredServiceNam
 	newEntry := entry.(ServiceVirtualIP)
 
 	// Check to see if the slice already contains the same ips.
-	if !vipSliceEqualsMapKeys(newEntry.ManualIPs, assignedIPs) {
+	if !stringslice.EqualMapKeys(newEntry.ManualIPs, assignedIPs) {
 		newEntry.ManualIPs = slices.Clone(ips)
 		newEntry.ModifyIndex = idx
 
@@ -1193,18 +1194,6 @@ func (s *Store) AssignManualServiceVIPs(idx uint64, psn structs.PeeredServiceNam
 	return true, maps.SliceOfKeys(modifiedEntries), nil
 }
 
-func vipSliceEqualsMapKeys(a []string, b map[string]struct{}) bool {
-	if len(a) != len(b) {
-		return false
-	}
-	for _, ip := range a {
-		if _, ok := b[ip]; !ok {
-			return false
-		}
-	}
-	return true
-}
-
 func updateVirtualIPMaxIndexes(txn WriteTxn, idx uint64, partition, peerName string) error {
 	// update global max index (for snapshots)
 	if err := indexUpdateMaxTxn(txn, idx, tableServiceVirtualIPs); err != nil {
diff --git a/lib/stringslice/stringslice.go b/lib/stringslice/stringslice.go
index 7c32864b94..71e90dba2a 100644
--- a/lib/stringslice/stringslice.go
+++ b/lib/stringslice/stringslice.go
@@ -80,3 +80,17 @@ func CloneStringSlice(s []string) []string {
 	copy(out, s)
 	return out
 }
+
+// EqualMapKeys returns true if the slice equals the keys of
+// the map ignoring any ordering.
+func EqualMapKeys[V any](a []string, b map[string]V) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for _, ip := range a {
+		if _, ok := b[ip]; !ok {
+			return false
+		}
+	}
+	return true
+}
diff --git a/lib/stringslice/stringslice_test.go b/lib/stringslice/stringslice_test.go
index dd25071757..b861d9c38a 100644
--- a/lib/stringslice/stringslice_test.go
+++ b/lib/stringslice/stringslice_test.go
@@ -63,3 +63,28 @@ func TestMergeSorted(t *testing.T) {
 		})
 	}
 }
+
+func TestEqualMapKeys(t *testing.T) {
+	for _, tc := range []struct {
+		a    []string
+		b    map[string]int
+		same bool
+	}{
+		// same
+		{nil, nil, true},
+		{[]string{}, nil, true},
+		{nil, map[string]int{}, true},
+		{[]string{}, map[string]int{}, true},
+		{[]string{"a"}, map[string]int{"a": 1}, true},
+		{[]string{"b", "a"}, map[string]int{"a": 1, "b": 1}, true},
+		// different
+		{[]string{"a"}, map[string]int{}, false},
+		{[]string{}, map[string]int{"a": 1}, false},
+		{[]string{"b", "a"}, map[string]int{"c": 1, "a": 1, "b": 1}, false},
+		{[]string{"b", "a"}, map[string]int{"c": 1, "a": 1, "b": 1}, false},
+		{[]string{"b", "a", "c"}, map[string]int{"a": 1, "b": 1}, false},
+	} {
+		got := EqualMapKeys(tc.a, tc.b)
+		require.Equal(t, tc.same, got)
+	}
+}