@Test
    public void testFetchOnCompletedFetchesForPausedAndResumedPartitions() {
        buildFetcher();

        assignFromUser(singleton(tp0));
        subscriptions.seek(tp0, 0);

        assertEquals(1, sendFetches());

        subscriptions.pause(tp0);

        client.prepareResponse(fullFetchResponse(tidp0, records, Errors.NONE, 100L, 0));
        networkClientDelegate.poll(time.timer(0));

        assertEmptyFetch("Should not return any records or advance position when partition is paused");

        assertTrue(fetcher.hasCompletedFetches(), "Should still contain completed fetches");
        assertFalse(fetcher.hasAvailableFetches(), "Should not have any available (non-paused) completed fetches");
        assertEquals(0, sendFetches());

        subscriptions.resume(tp0);

        assertTrue(fetcher.hasAvailableFetches(), "Should have available (non-paused) completed fetches");

        networkClientDelegate.poll(time.timer(0));
        Map<TopicPartition, List<ConsumerRecord<byte[], byte[]>>> fetchedRecords = fetchRecords();
        assertEquals(1, fetchedRecords.size(), "Should return records when partition is resumed");
        assertNotNull(fetchedRecords.get(tp0));
        assertEquals(3, fetchedRecords.get(tp0).size());

        networkClientDelegate.poll(time.timer(0));
        assertEmptyFetch("Should not return records or advance position after previously paused partitions are fetched");
        assertFalse(fetcher.hasCompletedFetches(), "Should no longer contain completed fetches");
    }
Test the case where the client makes a post KIP-74 FetchRequest, but the server replies with only a
partial request. For v3 and later FetchRequests, the implementation of KIP-74 changed the behavior
so that at least one message is always returned. Therefore, this case should not happen, and it indicates
that an internal error has taken place.
clients/src/test/java/org/apache/kafka/clients/consumer/internals/FetchRequestManagerTest.java