@Test
    public void testVerificationStateEntryExpiration() {
        VerificationStateEntry originalEntry = stateManager.maybeCreateVerificationStateEntry(producerId, 0, epoch);

        // Before timeout, we do not remove. Note: Accessing the verification entry does not update the time.
        time.sleep(producerStateManagerConfig.producerIdExpirationMs() / 2);
        stateManager.removeExpiredProducers(time.milliseconds());
        assertEquals(originalEntry, stateManager.verificationStateEntry(producerId));

        time.sleep((producerStateManagerConfig.producerIdExpirationMs() / 2) + 1);
        stateManager.removeExpiredProducers(time.milliseconds());
        assertNull(stateManager.verificationStateEntry(producerId));
    }
Test that marking a snapshot for deletion when the file has already been deleted
returns None instead of the SnapshotFile. The snapshot file should be removed from
the in-memory state of the ProducerStateManager. This scenario can occur during log
recovery when the intermediate ProducerStateManager instance deletes a file without
updating the state of the "real" ProducerStateManager instance which is passed to the Log.
storage/src/test/java/org/apache/kafka/storage/internals/log/ProducerStateManagerTest.java