PSA - Do not assign the result of ::getenv to a std::string

This is a lesson I apparently have to learn repeatedly. Many, many times. Way too many times.

Unit tests are failing, I'm too ADD to actually read the error message for comprehension, fart around changing things to try to find why the exception is being thrown, then spontaneously remember "oh, yeah, ::getenv will return NULL if the variable hasn't been defined, and assigning a NULL to a std::string is Bad Juju.

Wasted a whole day on this nonsense.

I know this. I have known this for years, and I still make this mistake.

Blah. Needed to vent.

https://redd.it/1tx3eb6
@r_cpp