test_describe_formatted hasn't been doing anything in a while since the hive-jdbc jar is not in the classpath, hence bin/run-jdbc-client.sh always produces empty STDOUT. So exec_and_compare_hive_and_impala_hs2 always compare two empty result sets and always succeed.
I found the issue during https://gerrit.cloudera.org/#/c/16450/ This sets the classpath for run-jdbc-client.sh correctly. But this change request failed during the pre-commit tests because it activated test_describe_formatted and turned out it is failing.
Seems like the problem is that Hive outputs some extra table statistics under "Table parameters", e.g.:
'','numFiles ','24 '
'','numPartitions ','24 '
'','numRows ','0 '
'','rawDataSize ','0 '
'','totalSize ','489934 '