Hi kafka team: I raise a pr https://github.com/apache/kafka/pull/13965 to fix https://issues.apache.org/jira/browse/KAFKA-15106, it mentions some serious bug and no one check it for a long time, plz help me review if could. thx!
these bugs are in org.apache.kafka.clients.consumer.internals.AbstractStickyAssignor.ConstrainedAssignmentBuilder#ConstrainedAssignmentBuilder and all of them could cause rebalance stuck for ever, and they could occur in production environment, very, very, very easy.
