Previously the random port was a default-arg expression
(`_rando_port: str = random.randint(1000, 9999)`) — evaluated
ONCE at module import time, making it a per-process singleton.
Two parallel pytest sessions had a 1/9000 birthday-pair chance
of picking the same port; when it hit, every `reg_addr`-using
test in BOTH runs would cascade-fail with "Address already in
use".
Switch to per-call `random.randint()` salted with `os.getpid()`
so:
- within one session: two calls return distinct ports — e.g.
`test_tpt_bind_addrs::bind-subset-reg` now actually gets two
different reg addrs on the TCP backend (it was silently
duplicating before),
- across parallel sessions: pid salt biases each process's
port choices apart, making cross-run collisions
vanishingly rare.
Drop the bogus `: str` annotation (was always `int`). UDS already gets
per-process isolation via `UDSAddress.get_random()`'s `@<pid>`
socket-path suffix, so no change needed there.
(this patch was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
Gud Boi
7c5dd4d033