Resolve#474 with a new `tests/trionics/test_taskc.py` (9
tests) covering the `trio.Nursery.start()` wrapper landed in
PR #464, incl. the `modden.runtime.progman.open_wks()` use
case dug out as a minimal repro.
Deats,
- the lossy `RuntimeError('child exited without calling
task_status.started()')` only fires when the child absorbs
its ambient cancel pre-`.started()` (graceful-teardown
pattern); a well-behaved child surfaces `Cancelled` direct
from `.start()` on `trio` 0.29 - verified empirically 1st.
- `test_sibling_err_not_masked_by_startup_rte`: the `modden`
case; ONLY the root-cause sibling `ValueError` escapes the
nursery with the wrapper vs. bare-`.start()`'s lossy
riding-along startup-RTE noise.
- `test_pure_oob_cancel_not_morphed_to_rte`: plain ancestor
`cs.cancel()` exits clean vs. bare's eg-wrapped RTE.
- `test_genuine_startup_rte_still_raised`: sans cancellation
the protocol-bug RTE re-raises same as bare.
- `test_childs_own_rte_never_demoted_to_cancel`: exact-msg +
`isinstance`-guard regression cover; a child's own
`RuntimeError('never got started!')`/`RuntimeError(1234)`
never demotes to a `Cancelled`.
- `test_started_value_and_args_passthru`: positional args,
`name=` and `.started()`-value forwarding.
Also,
- `use_start_or_cancel=False` params pin upstream `trio`'s
current lossy behaviour as wart-documentation: a break on
a `trio` upgrade likely means new upstream porcelain and
the wrapper deserves a re-audit.
- verified 0 flakes over 50 hammer runs + 2 impl mutations
each caught by exactly the targeted tests.
Prompt-IO: ai/prompt-io/claude/20260702T161624Z_65bf9df5_prompt_io.md
(this patch was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code