Used
sed -r -i -e '/ helpers =/ s/$/\nlocal itp = helpers.gen_itp(it)/; s/^(\s*)it\(/\1itp(/' test/unit/**/*_spec.lua
to alter all tests. Locally they all run fine now.
Reasoning:
1. General: state from one test should not affect other tests.
2. Local: travis build is failing with something which may be an output of
garbage collector. This should prevent state of the garbage collector from
interferring as well.
Move typedef expand_T to types.h for tests
Fix lint error for old style comments
Describe 'check_ff_value' valid values as an initial test.
Fix 'get_sts_value' comment inaccuracy and add unit test for it