Helpful when comparing expected/unexpected outputs against each other for working/broken code.
Also account for TimeoutExpired.output being None and halt instead of re-raising.
Partial revert of fab085c15f7221986f73af7e05e799edf3eadaf0
subprocess.run(..., text=True) is not sufficient to make the TimeoutExpired exception stop using byte buffers. This is a known issue, see: https://github.com/python/cpython/issues/87597
All touched Python scripts already assume and require UTF8, so manually
specifying encoding or decoding for functions in the subprocess module
is redundant to just using text=True, which exists since Python 3.7
We would only modify the parent process' first --tmpdir arg.
Now we tack on an additional --tmpdir after the parent's arguments. Also simplifies the code.
Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
