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.
Actual value on FreeBSD is -31, UV_EMLINK was obtained from
/usr/include/asm-generic/errno-base.h (there EMLINK is defined as 31 there).
This may actually be something else, but I do not think so as “Too many links”
description also fits in. [Man page][1] agrees with me, search for `[EMLINK]`
([linux man page][2] also specifies ELOOP explicitly in a similar section).
[1]: https://www.freebsd.org/cgi/man.cgi?query=open&sektion=2
[2]: http://man7.org/linux/man-pages/man3/open.3p.html