Add `test_subint_forkserver_key_errors_cleanly` — a tn-tier
regression guard that pins down the variant-2 reservation
contract: the `'subint_forkserver'` key in
`_spawn._methods` MUST raise `NotImplementedError` today,
not silently dispatch to `main_thread_forkserver_proc`.
The transient alias-state existed briefly during the rename
(commit `57dae0e4`'s "Split forkserver backend into variant
1/2 mods" landed the alias; `5e83881f` flipped it to the
stub). Without a guard, a future refactor could easily
re-collapse the two keys back to a single coro and silently
break the variant-1 / variant-2 contract.
Also asserts the stub's error msg surfaces the two pointers
an operator hitting it actually needs:
- `'main_thread_forkserver'` — the working backend they
prolly meant,
- `'msgspec#1026'` — the upstream blocker that has to land
before variant-2 can ship.
(this patch was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
Rename `tests/spawn/test_subint_forkserver.py` →
`test_main_thread_forkserver.py` and migrate its imports +
internal refs to the new canonical names:
- `fork_from_worker_thread`, `wait_child` → from
`tractor.spawn._main_thread_forkserver`.
- `run_subint_in_worker_thread` → still from `_subint_forkserver`
(variant-2 primitive).
- Module docstring + tier-3 fixture + the `*_spawn_basic` test fn
renamed for variant-1-honesty.
- Orphan-harness subprocess argv flipped from `'subint_forkserver'`
→ `'main_thread_forkserver'`.
`ai/conc-anal/subint_fork_from_main_thread_smoketest.py` imports split
the same way.
`tractor/spawn/_subint_forkserver.py` drops the backward- compat
re-exports of the fork primitives — the only consumers (test file
+ smoketest) now import from `_main_thread_forkserver` directly.
(this patch was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
Gud Boi