Bottle up the diagnostic primitives that actually cracked the
silent mid-suite hangs in the `subint` spawn-backend bringup (issue
there" session has them on the shelf instead of reinventing from
scratch.
Deats,
- `dump_on_hang(seconds, *, path)` — context manager wrapping
`faulthandler.dump_traceback_later()`. Critical gotcha baked in:
dumps go to a *file*, not `sys.stderr`, bc pytest's stderr
capture silently eats the output and you can spend an hour
convinced you're looking at the wrong thing
- `track_resource_deltas(label, *, writer)` — context manager
logging per-block `(threading.active_count(),
len(_interpreters.list_all()))` deltas; quickly rules out
leak-accumulation theories when a suite progressively worsens (if
counts don't grow, it's not a leak, look for a race on shared
cleanup instead)
- `resource_delta_fixture(*, autouse, writer)` — factory returning
a `pytest` fixture wrapping `track_resource_deltas` per-test; opt
in by importing into a `conftest.py`. Kept as a factory (not a
bare fixture) so callers own `autouse` / `writer` wiring
Also,
- export the three names from `tractor.devx`
- dep-free on py<3.13 (swallows `ImportError` for `_interpreters`)
- link back to the provenance in the module docstring (issue #379 /
commit `26fb820`)
(this patch was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
(cherry picked from commit 09466a1e9d)
Gud Boi