I have >1 times to encounter some feature test failures due to reported
missing stuffs.
e.g.
1. I did not have pl/python installed in my hawq build so
UDF/sql/function_set_returning.sql fails to "create language plpythonu"
This makes this case fails.
2. Sometimes I forgot to source a greenplum.sh, then all cases run
with failures due to missing psql.
We seem to be able to improve.
1) Sanity-check some file existence in common code, e.g.
psql, gpdiff.pl,
2) Some cases could do sanity-check in their own test constructor functions,
e.g. if the case uses the extension plpython, the test case should
check it itself.
More thoughts?
