fix: isolate in-memory client persistence

memory_auth_test.go

@@ -10,7 +10,6 @@ import (
 	"path/filepath"
 	"reflect"
 	"strings"
-	"sync"
 	"testing"
 )
 
@@ -136,18 +135,31 @@ func TestMemoryRefreshCallbackCanReadCurrentAuth(t *testing.T) {
 	}
 }
 
-func TestMemoryRefreshCallbackCanAcquireApplicationLock(t *testing.T) {
-	var persistenceMu sync.Mutex
-	client, _, server := newMemoryRefreshClient(t, func(AuthData) error {
-		persistenceMu.Lock()
-		defer persistenceMu.Unlock()
-		return nil
+func TestMemoryRefreshCallbackCanPersistIndependently(t *testing.T) {
+	persistencePath := filepath.Join(t.TempDir(), "persisted-auth.json")
+	client, _, server := newMemoryRefreshClient(t, func(authData AuthData) error {
+		payload, err := authData.MarshalJSON()
+		if err != nil {
+			return err
+		}
+		return os.WriteFile(persistencePath, payload, 0o600)
 	})
 	defer server.Close()
 
 	if err := client.refreshToken(context.Background()); err != nil {
 		t.Fatal(err)
 	}
+	payload, err := os.ReadFile(persistencePath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var persisted AuthData
+	if err := persisted.UnmarshalJSON(payload); err != nil {
+		t.Fatal(err)
+	}
+	if persisted.ServiceToken != "new-token" || persisted.CUserID != "new-c-user" {
+		t.Fatalf("persisted auth = %#v", persisted)
+	}
 }
 
 func TestMemoryRefreshPersistsGeneratedIdentity(t *testing.T) {