Track T by default, because this job TIMED OUT. The source path says what a job compiles, not what went wrong, and a timeout did not fail in any of its sources — it ran out of budget. Guessing a lane from the path is the wrong turn bug-t-a-timeout-bisects-to-an-innocent-commit was filed to stop, so a timeout stays T's until someone shows otherwise. Re-lane it if the budget was not the problem.

It was executing line 2 of 11 when the budget ran out: tools/expect_same.sh test_nilpy_noleak "$(/tmp/test_nilpy_noleak | tail -n 1)" "PYLEAK OK". That is where to look; it is not an accusation against that line.

The SLUG names test_nilpy_format_and_set_do_not_leak_a_temporary_list_per_call, and that is not what broke. The slug is derived from the job's src: selector so that it stays stable across a renumbering — it is the dedupe key and the close key — but src: says what the job is ABOUT. The failing step names expect_same. Read the Failing step: bullet, not the file name in the title, before you reproduce anything: the row the slug names may be passing.

origin/master has advanced 9 commit(s) since this sha. Re-verify at current HEAD before acting — the callback is tagged to the sha that was tested, which may no longer be the state of the tree.

regression: lib-test#src:test/test_nilpy_format_and_set_do_not_leak_a_temporary_list_per_call.npy at ebe1a9b4d011 in step 2/11, tools/expect_same.sh test_nilpy_noleak "$(/tmp/test_nilpy_noleak | tail -n 1)" "PYLEAK OK" (auto-filed by twatch)

• Type: regression (auto-filed by Track T watcher, host borg, twatch f35167cd4e55). Untriaged.
• Found: 2026-09-23T21:46:13Z
• Test source: test/test_nilpy_format_and_set_do_not_leak_a_temporary_list_per_call.npy tools/expect_same.sh
• Failing step: line 2 of 11 of the job's recipe; it names tools/expect_same.sh.

  tools/expect_same.sh test_nilpy_noleak "$(/tmp/test_nilpy_noleak | tail -n 1)" "PYLEAK OK"
  
  

Repro

tools/testmgr.py --tier full --job 'lib-test#src:test/test_nilpy_format_and_set_do_not_leak_a_temporary_list_per_call.npy' at ebe1a9b4d0110b63c3e8e4a3a0d60f5c069ab131

Range

The named sha ebe1a9b4d011 CANNOT be the cause — it touches no buildable file (docs / tickets / tstate only). It is the sha that was TESTED, i.e. the upper bound of an untested range; the cause is somewhere below it.

bad ebe1a9b4d011, last good 77eff6982552, 2 commit(s) in range — the watcher narrows this by idle bisect; check tstate/TSTATE.md for the current range.

Log tail

ok: /tmp/testmgr-scratch-980262/test_nilpy_noleak  [code=657646B  data=100700B  bss=72012B  procs=2247  codeseg=659168B]

Stub ticket: signal only. Track T agent (face 2) enriches or a dev track takes it from the repro line.

Log

• 2026-09-23 — the borg watcher saw lib-test#src:test/test_nilpy_format_and_set_do_not_leak_a_temporary_list_per_call.npy GREEN at 434cc8f7ff79 (tier full) and did NOT close this: this is a repeat stub (regression-lib-test-test-nilpy-format-and-set-do-not-leak-a-temporary-list-per-call-2, not regression-lib-test-test-nilpy-format-and-set-do-not-leak-a-temporary-list-per-call) — the job already went red, was closed, and came back, so one green is the outcome a live intermittent bug produces most of the time. The green is recorded because it is evidence and because a ticket that stops moving with no reason reads as forgotten; closing this one is a human's call.
• 2026-09-24 — the borg watcher saw lib-test#src:test/test_nilpy_format_and_set_do_not_leak_a_temporary_list_per_call.npy GREEN at 692ea558bbe4 (tier full) and did NOT close this: this is a repeat stub (regression-lib-test-test-nilpy-format-and-set-do-not-leak-a-temporary-list-per-call-2, not regression-lib-test-test-nilpy-format-and-set-do-not-leak-a-temporary-list-per-call) — the job already went red, was closed, and came back, so one green is the outcome a live intermittent bug produces most of the time. The green is recorded because it is evidence and because a ticket that stops moving with no reason reads as forgotten; closing this one is a human's call.
• 2026-09-24 — the borg watcher saw lib-test#src:test/test_nilpy_format_and_set_do_not_leak_a_temporary_list_per_call.npy GREEN at e09adcd641b6 (tier full) and did NOT close this: this is a repeat stub (regression-lib-test-test-nilpy-format-and-set-do-not-leak-a-temporary-list-per-call-2, not regression-lib-test-test-nilpy-format-and-set-do-not-leak-a-temporary-list-per-call) — the job already went red, was closed, and came back, so one green is the outcome a live intermittent bug produces most of the time. The green is recorded because it is evidence and because a ticket that stops moving with no reason reads as forgotten; closing this one is a human's call.
• 2026-09-25 — the borg watcher saw lib-test#src:test/test_nilpy_format_and_set_do_not_leak_a_temporary_list_per_call.npy GREEN at fdca56b72841 (tier full) and did NOT close this: this is a repeat stub (regression-lib-test-test-nilpy-format-and-set-do-not-leak-a-temporary-list-per-call-2, not regression-lib-test-test-nilpy-format-and-set-do-not-leak-a-temporary-list-per-call) — the job already went red, was closed, and came back, so one green is the outcome a live intermittent bug produces most of the time. The green is recorded because it is evidence and because a ticket that stops moving with no reason reads as forgotten; closing this one is a human's call.

Closed (2026-10-02, frankuser): a budget timeout, removed twice over

It was never a leak. The job ran out of its 90 s unit budget on a loaded borg. On 2026-09-25, N in the fixture was cut from 12000 to 1000 (see the fixture's own "N IS A SLOPE, NOT A SOAK" note), and every borg run logged above since then is green.

The fixture was still slow for its size: 5.0 s on plexus against CPython's 0.23 s. Profiling found the cause. pyiter_has cleared about 46 Variant temps on every element step. It now has a fast path for list, range and generator cursors, and the fixture runs in 3.6 s. The deeper cost, an exception frame around every routine with a managed result, is filed as perf-a-a-routine-with-a-managed-result-pays-an-exception-frame-even-when-its-body-cannot-raise.