add newTokenIsDifferent test

src/test/java/com/ddf/vodsystem/security/TokenServiceTest.java

@@ -304,6 +304,24 @@ class TokenServiceTest {
                     .orElseThrow(() -> new AssertionError("no unused token was saved"));
             assertNull(newToken.getTokenFamily().getRevokedAt());
         }
-    }
 
+        @Test
+        void unusedToken_newTokenIsDifferentFromOldToken() {
+            TokenFamily tokenFamily = new TokenFamily();
+            tokenFamily.setId(1L);
+            tokenFamily.setUser(createUser(1L, "user", "user"));
+            tokenFamily.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            RefreshToken refreshToken = new RefreshToken();
+            refreshToken.setTokenHash(rawToken.getBytes());
+            refreshToken.setTokenFamily(tokenFamily);
+            refreshToken.setExpiresAt(Instant.now(clock).plusSeconds(10));
+
+            when(refreshTokenRepository.findByHash(any()))
+                    .thenReturn(Optional.of(refreshToken));
+
+            TokenService.Rotation rotation = tokenService.rotate(rawToken);
+            assertNotEquals(rawToken, rotation.newRefreshToken());
+        }
+    }
 }