In PIG-5085 we changed the behavior of FLATTEN on map.
(I didn't even know this was even allowed until I saw the following test failure.)
e2e nightly FOREACH_6 started failing after this change.
'num' => 6,
'pig' => q\register :FUNCPATH:/testudf.jar;
a = load ':INPATH:/singlefile/studenttab10k' as (name, age, gpa);
b = foreach a generate flatten(name) as n, flatten(org.apache.pig.test.udf.evalfunc.CreateMap((chararray)name, gpa)) as m;
store b into ':OUTPATH:' using org.apache.pig.test.udf.storefunc.StringStore();\,