Github user walterddr commented on the issue:
https://github.com/apache/flink/pull/5070
@twalthr I think my previous unit test method was not correct. Since
TableAPI always use `java.util.HashMap` per flink documentation. I think it is
safe to directly use `$leftTerm.equals($rightTerm)` and it should always be
using `java.util.AbstractMap.equals` implementation. Do you think I should add
extra check or do you think the `isMap(resultType)` should be suffice? ---
