Previous KafkaStreamsTest takes 2min20s on my local laptop, because lots of its integration test which is producing / consuming records, and checking state directory file system takes lots of time. On the other hand, these tests should be well simplified with mocks.
This test reduces the test from a clumsy integration test class into a unit tests with mocks of its internal modules. And some other test functions should not be in KafkaStreamsTest actually and have been moved to other modular test classes. Now it takes 2s.
Also it helps removing the potential flakiness of the following (some of them are claimed resolved only because we have not seen them recently, but after looking at the test code I can verify they are still flaky):
* KAFKA-5818 (the original JIRA ticket indeed exposed a real issue that has been fixed, but the test itself remains flaky)
* KAFKA-6215
* KAFKA-7921
* KAFKA-7990
* KAFKA-8319
* KAFKA-8427
Reviewers: Bill Bejeck <bill@confluent.io>, John Roesler <john@confluent.io>, Bruno Cadonna <bruno@confluent.io>
This commit was cherry-picked from trunk and adapted.
Co-authored-by: Guozhang Wang <wangguoz@gmail.com>
Reviewers: Guozhang Wang <wangguoz@gmail.com>
Bruno Cadonna