File size: 20,071 Bytes
9a46c96
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
import json
import hashlib
import os
import signal
import subprocess
import sys
from pathlib import Path

import pytest

import dlb.runner as runner_module
from dlb.runner import RunRequest, run_experiment


class FakeAdapter:
    def __init__(
        self, command: list[str], records: list[dict[str, object]], identity: str = "tests.fake_adapter:v1"
    ) -> None:
        self.command = command
        self.records = records
        self.identity = identity
        self.calls = 0

    def build_command(self, request: RunRequest, run_dir: Path) -> list[str]:
        del request, run_dir
        return self.command

    def convert_outputs(self, request: RunRequest, run_dir: Path) -> list[dict[str, object]]:
        del request, run_dir
        self.calls += 1
        return self.records


def make_records(count: int) -> list[dict[str, object]]:
    return [
        {
            "sample_id": index,
            "text": f"sample {index}",
            "token_ids": [index + 1],
            "seed": 42,
            "generation_seconds": 0.25,
        }
        for index in range(count)
    ]


def make_request(command: list[str] | None = None) -> RunRequest:
    return RunRequest(
        run_id="flm-lm1b-steps-2",
        model_id="flm",
        dataset_id="lm1b",
        step_count=2,
        seed=42,
        sample_count=2,
        command=command,
    )


def prepare_canonical_root(
    root: Path, *, source_sha: str = "a" * 40, checkpoint_payload: bytes = b"checkpoint"
) -> None:
    """Create the minimal canonical provenance inputs for the FLM/LM1B cell."""

    project_root = Path(__file__).parents[1]
    (root / "configs").mkdir(exist_ok=True)
    (root / "artifacts").mkdir(exist_ok=True)
    (root / "configs" / "experiments.yaml").write_text(
        (project_root / "configs" / "experiments.yaml").read_text()
    )
    manifest = root / "artifacts" / "checkpoints.yaml"
    manifest.write_text((project_root / "artifacts" / "checkpoints.yaml").read_text())
    (root / "artifacts" / "source_lock.json").write_text(
        json.dumps({"sources": {"flm": {"commit": source_sha}}})
    )
    checkpoint = root / "checkpoints" / "official" / "flm_ckpt" / "lm1b" / "lm1b_flm.ckpt"
    checkpoint.parent.mkdir(parents=True, exist_ok=True)
    checkpoint.write_bytes(checkpoint_payload)


def test_runner_records_command_failure(tmp_path: Path) -> None:
    """Catch child failures that lose the exit code or diagnostic logs."""

    command = [sys.executable, "-c", "import sys; print('out'); print('bad', file=sys.stderr); sys.exit(7)"]
    prepare_canonical_root(tmp_path)
    result = run_experiment(make_request(command), tmp_path, adapter=FakeAdapter(command, make_records(2)))

    assert result.status == "failed"
    assert result.returncode == 7
    failure = json.loads((result.run_dir / "failure.json").read_text())
    assert failure["stage"] == "command"
    assert failure["exit_code"] == 7
    assert failure["stderr_tail"] == "bad\n"
    assert (result.run_dir / "stdout.log").read_text() == "out\n"


def test_runner_skips_only_matching_valid_publication(tmp_path: Path) -> None:
    """Catch resume logic that trusts metadata without checking output and provenance."""

    prepare_canonical_root(tmp_path)
    command = [sys.executable, "-c", "print('ok')"]
    adapter = FakeAdapter(command, make_records(2))
    request = make_request(command)

    first = run_experiment(request, tmp_path, adapter=adapter)
    second = run_experiment(request, tmp_path, adapter=adapter)

    assert first.status == "succeeded"
    assert second.status == "skipped"
    assert adapter.calls == 1
    metadata = json.loads((first.run_dir / "run_metadata.json").read_text())
    assert metadata["command"] == command
    assert metadata["command_sha256"]
    assert metadata["source_sha256"] == "a" * 40
    assert metadata["checkpoint_lock_id"].startswith("recipe:flm_lm1b_official_ckpt:")


def test_runner_reruns_when_checkpoint_identity_changes(tmp_path: Path) -> None:
    """Catch stale reuse after the checkpoint lock resolves to different content."""

    prepare_canonical_root(tmp_path)
    command = [sys.executable, "-c", "print('ok')"]
    adapter = FakeAdapter(command, make_records(2))
    first_request = make_request(command)
    assert run_experiment(first_request, tmp_path, adapter=adapter).status == "succeeded"
    prepare_canonical_root(tmp_path, checkpoint_payload=b"changed-checkpoint")
    assert run_experiment(first_request, tmp_path, adapter=adapter).status == "succeeded"
    assert adapter.calls == 2


def test_runner_does_not_publish_metadata_after_conversion_failure(tmp_path: Path) -> None:
    """Catch a success marker published before converted samples satisfy the contract."""

    prepare_canonical_root(tmp_path)
    command = [sys.executable, "-c", "print('ok')"]
    result = run_experiment(
        make_request(command),
        tmp_path,
        adapter=FakeAdapter(command, [{**make_records(1)[0], "text": ""}]),
    )

    assert result.status == "failed"
    assert result.returncode == 1
    assert not (result.run_dir / "run_metadata.json").exists()
    assert json.loads((result.run_dir / "failure.json").read_text())["stage"] == "conversion"


def test_failed_rerun_removes_stale_success_metadata(tmp_path: Path) -> None:
    """Catch a failed rerun retaining an old success marker for different provenance."""

    prepare_canonical_root(tmp_path)
    command = [sys.executable, "-c", "print('ok')"]
    first_request = make_request(command)
    assert run_experiment(
        first_request, tmp_path, adapter=FakeAdapter(command, make_records(2))
    ).status == "succeeded"
    prepare_canonical_root(tmp_path, source_sha="x" * 40)

    result = run_experiment(
        first_request,
        tmp_path,
        adapter=FakeAdapter(command, [{**make_records(1)[0], "text": ""}]),
    )

    assert result.status == "failed"
    assert not (result.run_dir / "run_metadata.json").exists()


def test_runner_refuses_symlinked_log_target(tmp_path: Path) -> None:
    """Catch a prepared log symlink that would truncate a file outside the run."""

    prepare_canonical_root(tmp_path)
    command = [sys.executable, "-c", "print('ok')"]
    request = make_request(command)
    run_dir = tmp_path / "results" / "samples" / "lm1b" / "flm" / "steps_2"
    run_dir.mkdir(parents=True)
    outside = tmp_path / "outside.log"
    outside.write_text("sentinel\n")
    (run_dir / "stdout.log").symlink_to(outside)

    try:
        run_experiment(request, tmp_path, adapter=FakeAdapter(command, make_records(2)))
    except ValueError as error:
        assert "symlink" in str(error)
    else:
        raise AssertionError("symlinked log target was accepted")
    assert outside.read_text() == "sentinel\n"


def test_runner_resolves_checkpoint_identity_from_coverage_lock(tmp_path: Path) -> None:
    """Catch CLI requests that cannot bind a coverage cell to its checkpoint lock."""

    project_root = Path(__file__).parents[1]
    (tmp_path / "configs").mkdir()
    (tmp_path / "artifacts").mkdir()
    (tmp_path / "configs" / "experiments.yaml").write_text(
        (project_root / "configs" / "experiments.yaml").read_text()
    )
    checkpoints_manifest = tmp_path / "artifacts" / "checkpoints.yaml"
    checkpoints_manifest.write_text((project_root / "artifacts" / "checkpoints.yaml").read_text())
    (tmp_path / "artifacts" / "source_lock.json").write_text(
        json.dumps({"sources": {"duo": {"commit": "a" * 40}}})
    )
    files = [
        {
            "path": "checkpoints/reference_reproduction/flm_baselines/lm1b/lm1b_Duo.ckpt",
            "size_bytes": 3,
            "sha256": "b" * 64,
        }
    ]
    (tmp_path / "artifacts" / "checkpoint_lock.json").write_text(
        json.dumps(
            {
                "manifest_sha256": hashlib.sha256(checkpoints_manifest.read_bytes()).hexdigest(),
                "resources": {
                    "flm_lm1b_reproductions": {
                        "status": "downloaded",
                        "files": files,
                    }
                },
            }
        )
    )
    command = [sys.executable, "-c", "print('ok')"]
    request = RunRequest(
        run_id="duo-lm1b-steps-2",
        model_id="duo",
        dataset_id="lm1b",
        step_count=2,
        seed=42,
        sample_count=2,
        command=command,
    )

    result = run_experiment(request, tmp_path, adapter=FakeAdapter(command, make_records(2)))

    metadata = json.loads((result.run_dir / "run_metadata.json").read_text())
    manifest_sha = hashlib.sha256(checkpoints_manifest.read_bytes()).hexdigest()
    expected = hashlib.sha256(
        json.dumps(
            {
                "manifest_sha256": manifest_sha,
                "selector": {
                    "resource": "flm_lm1b_reproductions",
                    "path": "lm1b_Duo.ckpt",
                    "teacher_family": "uniform_duo",
                },
                "files": files,
            },
            sort_keys=True,
            separators=(",", ":"),
            ensure_ascii=False,
        ).encode("utf-8")
    ).hexdigest()
    assert metadata["checkpoint_sha256"] == expected
    assert (
        metadata["checkpoint_lock_id"]
        == "flm_lm1b_reproductions:" + manifest_sha + ":lm1b_Duo.ckpt"
    )


def test_runner_resolves_recipe_checkpoint_identity(tmp_path: Path) -> None:
    """Catch supported recipe-backed cells that cannot acquire a checkpoint identity."""

    project_root = Path(__file__).parents[1]
    (tmp_path / "configs").mkdir()
    (tmp_path / "artifacts").mkdir()
    (tmp_path / "configs" / "experiments.yaml").write_text(
        (project_root / "configs" / "experiments.yaml").read_text()
    )
    (tmp_path / "artifacts" / "checkpoints.yaml").write_text(
        (project_root / "artifacts" / "checkpoints.yaml").read_text()
    )
    (tmp_path / "artifacts" / "source_lock.json").write_text(
        json.dumps({"sources": {"candi": {"commit": "a" * 40}}})
    )
    checkpoint = tmp_path / "checkpoints" / "reference_reproduction" / "candi" / "owt" / "model.bin"
    checkpoint.parent.mkdir(parents=True)
    checkpoint.write_bytes(b"model")
    command = [sys.executable, "-c", "print('ok')"]
    request = RunRequest(
        run_id="candi-owt-steps-2",
        model_id="candi",
        dataset_id="owt",
        step_count=2,
        seed=42,
        sample_count=2,
        command=command,
    )

    result = run_experiment(request, tmp_path, adapter=FakeAdapter(command, make_records(2)))

    metadata = json.loads((result.run_dir / "run_metadata.json").read_text())
    assert metadata["checkpoint_lock_id"].startswith("recipe:candi_owt:")
    assert metadata["checkpoint_sha256"]


def test_recipe_checkpoint_identity_ignores_empty_runtime_logs(tmp_path: Path) -> None:
    """Catch successful recipe outputs being rejected because Hydra wrote empty logs."""

    project_root = Path(__file__).parents[1]
    (tmp_path / "configs").mkdir()
    (tmp_path / "artifacts").mkdir()
    (tmp_path / "configs" / "experiments.yaml").write_text(
        (project_root / "configs" / "experiments.yaml").read_text()
    )
    (tmp_path / "artifacts" / "checkpoints.yaml").write_text(
        (project_root / "artifacts" / "checkpoints.yaml").read_text()
    )
    (tmp_path / "artifacts" / "source_lock.json").write_text(
        json.dumps({"sources": {"candi": {"commit": "a" * 40}}})
    )
    output = tmp_path / "checkpoints" / "reference_reproduction" / "candi" / "owt"
    output.mkdir(parents=True)
    (output / "model.bin").write_bytes(b"model")
    (output / "main.log").write_bytes(b"")
    (output / "stdout.log").write_bytes(b"")
    command = [sys.executable, "-c", "print('ok')"]
    request = RunRequest(
        run_id="candi-owt-steps-2",
        model_id="candi",
        dataset_id="owt",
        step_count=2,
        seed=42,
        sample_count=2,
        command=command,
    )

    result = run_experiment(request, tmp_path, adapter=FakeAdapter(command, make_records(2)))

    metadata = json.loads((result.run_dir / "run_metadata.json").read_text())
    assert metadata["checkpoint_lock_id"].startswith("recipe:candi_owt:")
    assert metadata["checkpoint_sha256"]


def test_runner_reruns_when_declared_adapter_identity_changes(tmp_path: Path) -> None:
    """Catch cache reuse after an adapter changes declared conversion semantics."""

    prepare_canonical_root(tmp_path)
    command = [sys.executable, "-c", "print('ok')"]
    request = make_request(command)
    first_adapter = FakeAdapter(command, make_records(2), identity="adapter-v1")
    second_adapter = FakeAdapter(command, make_records(2), identity="adapter-v2")

    assert run_experiment(request, tmp_path, adapter=first_adapter).status == "succeeded"
    assert run_experiment(request, tmp_path, adapter=second_adapter).status == "succeeded"
    assert second_adapter.calls == 1


def test_success_and_skip_clear_stale_failure_marker(tmp_path: Path) -> None:
    """Catch failure evidence surviving a later validated success or exact skip."""

    prepare_canonical_root(tmp_path)
    marker = tmp_path / "ran-once"
    command = [
        sys.executable,
        "-c",
        f"from pathlib import Path; import sys; p=Path({str(marker)!r}); "
        "(p.write_text('done') if not p.exists() else None); sys.exit(7 if p.read_text() == 'done' else 0)",
    ]
    request = make_request(command)
    failed = run_experiment(request, tmp_path, adapter=FakeAdapter(command, make_records(2)))
    assert failed.status == "failed"
    assert (failed.run_dir / "failure.json").exists()
    marker.write_text("succeeded")

    succeeded = run_experiment(request, tmp_path, adapter=FakeAdapter(command, make_records(2)))
    skipped = run_experiment(request, tmp_path, adapter=FakeAdapter(command, make_records(2)))

    assert succeeded.status == "succeeded"
    assert skipped.status == "skipped"
    assert not (succeeded.run_dir / "failure.json").exists()


def test_explicit_provenance_assertion_cannot_override_source_lock(tmp_path: Path) -> None:
    """Catch a caller spoofing source provenance instead of matching the canonical lock."""

    prepare_canonical_root(tmp_path)
    command = [sys.executable, "-c", "print('ok')"]
    request = RunRequest(**{**make_request(command).__dict__, "source_sha256": "x" * 40})

    try:
        run_experiment(request, tmp_path, adapter=FakeAdapter(command, make_records(2)))
    except ValueError as error:
        assert "source SHA" in str(error)
    else:
        raise AssertionError("mismatched source assertion was accepted")


def test_cli_reemits_child_sigterm_after_writing_failure(tmp_path: Path) -> None:
    """Catch CLI conversion of a child SIGTERM into an unrelated numeric exit status."""

    prepare_canonical_root(tmp_path)
    source_root = Path(__file__).parents[1] / "src"
    child = """
import os
import signal
import sys
from dlb import runner

class Adapter:
    identity = 'signal-adapter'
    def build_command(self, request, run_dir):
        return [sys.executable, '-c', 'import os, signal; os.kill(os.getpid(), signal.SIGTERM)']
    def convert_outputs(self, request, run_dir):
        return []

runner.load_adapter = lambda adapter_id: Adapter()
raise SystemExit(runner.main([
    '--root', sys.argv[1], '--model', 'flm', '--dataset', 'lm1b', '--steps', '2',
    '--num-samples', '2', '--seed', '42',
]))
"""
    environment = {**os.environ, "PYTHONPATH": str(source_root)}
    completed = subprocess.run([sys.executable, "-c", child, str(tmp_path)], env=environment)

    assert completed.returncode == -signal.SIGTERM
    run_dir = tmp_path / "results" / "samples" / "lm1b" / "flm" / "steps_2"
    assert json.loads((run_dir / "failure.json").read_text())["signal"] == signal.SIGTERM


def test_run_one_rejects_registry_invalid_step_before_fake_conda() -> None:
    """Catch shell validation that launches Conda or loses the registry error status."""

    project_root = Path(__file__).parents[1]
    environment = {
        **os.environ,
        "DLB_PYTHON": sys.executable,
        "DLB_CONDA": "/usr/bin/false",
    }
    completed = subprocess.run(
        [
            "bash",
            str(project_root / "scripts" / "run_one.sh"),
            "--model",
            "flm",
            "--dataset",
            "lm1b",
            "--steps",
            "3",
            "--num-samples",
            "1",
            "--seed",
            "42",
        ],
        env=environment,
        capture_output=True,
        text=True,
    )

    assert completed.returncode == 2
    assert "invalid step count 3" in completed.stderr


def test_validate_only_uses_rdlm_official_step_override(capsys) -> None:
    """Catch RDLM inheriting low-step many-grid cells after being marked official-only."""

    project_root = Path(__file__).parents[1]

    assert (
        runner_module.main(
            [
                "--root",
                str(project_root),
                "--model",
                "rdlm",
                "--dataset",
                "lm1b",
                "--steps",
                "1000",
                "--seed",
                "42",
                "--validate-only",
            ]
        )
        == 0
    )
    assert capsys.readouterr().out.strip() == "dlb-rdlm"
    with pytest.raises(SystemExit) as raised:
        runner_module.main(
            [
                "--root",
                str(project_root),
                "--model",
                "rdlm",
                "--dataset",
                "lm1b",
                "--steps",
                "32",
                "--seed",
                "42",
                "--validate-only",
            ]
        )
    assert raised.value.code == 2
    assert "invalid step count 32" in capsys.readouterr().err


@pytest.mark.parametrize("signum", [signal.SIGKILL, signal.SIGSTOP])
def test_cli_does_not_reset_uncatchable_signal_handlers(monkeypatch, tmp_path: Path, signum: int) -> None:
    """Catch attempts to reset SIGKILL/SIGSTOP before re-emitting a child signal."""

    reset_calls: list[int] = []
    kill_calls: list[tuple[int, int]] = []
    monkeypatch.setattr(runner_module, "run_experiment", lambda request, root: runner_module.RunResult("failed", tmp_path, -signum))
    monkeypatch.setattr(runner_module.os, "name", "posix")
    monkeypatch.setattr(signal, "signal", lambda observed, handler: reset_calls.append(observed))
    monkeypatch.setattr(runner_module.os, "kill", lambda process, observed: kill_calls.append((process, observed)))

    assert runner_module.main(["--root", str(tmp_path), "--model", "flm", "--dataset", "lm1b", "--steps", "2", "--seed", "42"]) == 128 + signum
    assert reset_calls == []
    assert kill_calls == [(os.getpid(), signum)]


@pytest.mark.skipif(os.name != "posix", reason="POSIX signal semantics")
def test_cli_reemits_child_sigkill_without_handler_reset(tmp_path: Path) -> None:
    """Catch SIGKILL propagation failing before the parent can self-send SIGKILL."""

    prepare_canonical_root(tmp_path)
    source_root = Path(__file__).parents[1] / "src"
    child = """
import os
import signal
import sys
from dlb import runner

class Adapter:
    identity = 'sigkill-adapter'
    def build_command(self, request, run_dir):
        return [sys.executable, '-c', 'import os, signal; os.kill(os.getpid(), signal.SIGKILL)']
    def convert_outputs(self, request, run_dir):
        return []

runner.load_adapter = lambda adapter_id: Adapter()
raise SystemExit(runner.main([
    '--root', sys.argv[1], '--model', 'flm', '--dataset', 'lm1b', '--steps', '2',
    '--num-samples', '2', '--seed', '42',
]))
"""
    completed = subprocess.run(
        [sys.executable, "-c", child, str(tmp_path)],
        env={**os.environ, "PYTHONPATH": str(source_root)},
    )

    assert completed.returncode == -signal.SIGKILL
    run_dir = tmp_path / "results" / "samples" / "lm1b" / "flm" / "steps_2"
    assert json.loads((run_dir / "failure.json").read_text())["signal"] == signal.SIGKILL