OBLITERATUS/tests/test_quality_policy.py

"""Tests for quality-policy immutability and mature-scope measurement."""

from __future__ import annotations

from copy import deepcopy
from datetime import date
import json
from pathlib import Path
import sys

import pytest
import yaml

from scripts import check_mutation_targets
from scripts import prepare_mutation_coverage
from scripts import run_prepared_mutmut
from scripts import check_quality_policy as quality


def _workflow_step(name: str) -> dict:
    workflow = yaml.safe_load(Path(".github/workflows/ci.yml").read_text())
    steps = workflow["jobs"]["quality-depth"]["steps"]
    matches = [step for step in steps if step.get("name") == name]
    assert len(matches) == 1
    return matches[0]


def test_mutation_campaign_uses_fork_safe_native_runtime_policy():
    pyproject = Path("pyproject.toml").read_text()
    mutmut_config = pyproject.split("[tool.mutmut]", maxsplit=1)[1].split(
        "\n[", maxsplit=1,
    )[0]
    mutation_step = _workflow_step("Run bounded selective mutation gate")
    mutation_run = mutation_step["run"]
    mutation_env = mutation_step["env"]
    quality_job = yaml.safe_load(Path(".github/workflows/ci.yml").read_text())["jobs"][
        "quality-depth"
    ]

    assert "mutate_only_covered_lines = true" in mutmut_config
    assert "timeout_constant = 2.0" in mutmut_config
    assert '"obliteratus/runtime_contracts.py"' in mutmut_config
    assert '"obliteratus/persistence_contracts.py"' in mutmut_config
    assert '"obliteratus/evaluation/lm_eval_integration.py"' in mutmut_config
    assert '"obliteratus/analysis/numerical_contracts.py"' in mutmut_config
    assert '"obliteratus/analysis/whitened_svd.py"' in mutmut_config
    assert "required_mutation_targets" in mutmut_config
    required_mutation_config = mutmut_config.split(
        "required_mutation_targets = [",
        maxsplit=1,
    )[1].split("]", maxsplit=1)[0]
    assert '"obliteratus/persistence_contracts.py"' in required_mutation_config
    assert '"obliteratus/reporting/report.py"' not in mutmut_config
    assert '"tests/test_runtime_contracts.py"' in mutmut_config
    assert '"tests/test_persistence_contracts.py"' in mutmut_config
    assert '"tests/test_lm_eval_reporting_contracts.py"' in mutmut_config
    assert '"tests/test_telemetry_failure_contracts.py"' not in mutmut_config
    assert '"tests/test_evaluation_reporting_contracts.py"' in Path(
        "scripts/run_repeat_gate.py",
    ).read_text()
    assert '"tests/test_lm_eval_reporting_contracts.py"' in Path(
        "scripts/run_repeat_gate.py",
    ).read_text()
    assert '"tests/test_telemetry_failure_contracts.py"' in Path(
        "scripts/run_repeat_gate.py",
    ).read_text()
    repeat_config = Path("scripts/run_repeat_gate.py").read_text()
    assert '"tests/test_checkpoint_atomicity.py"' in repeat_config
    assert '"tests/test_persistence_pipeline.py"' in repeat_config
    assert mutation_env == {
        "BLIS_NUM_THREADS": "1",
        "MKL_NUM_THREADS": "1",
        "NUMEXPR_NUM_THREADS": "1",
        "OMP_THREAD_LIMIT": "1",
        "OMP_NUM_THREADS": "1",
        "OPENBLAS_NUM_THREADS": "1",
        "VECLIB_MAXIMUM_THREADS": "1",
    }
    assert quality_job["timeout-minutes"] == 45
    assert "scripts/check_mutation_targets.py prepare" in mutation_run
    assert "scripts/prepare_mutation_coverage.py prepare-coverage --max-children 8" in mutation_run
    assert "scripts/prepare_mutation_coverage.py prepare-stats --max-children 8" in mutation_run
    assert "scripts/run_prepared_mutmut.py run --max-children 8" in mutation_run
    assert "OBLITERATUS_MUTMUT_REUSE_COVERAGE=1" not in mutation_run
    assert "scripts/check_mutation_targets.py check" in mutation_run
    assert '"$QUALITY_ENV/bin/mutmut" run --max-children 8' not in mutation_run
    assert "/usr/bin/time" in mutation_run
    timed_block = mutation_run.split("/usr/bin/time", maxsplit=1)[1]
    assert timed_block.index("scripts/prepare_mutation_coverage.py prepare-coverage") < (
        timed_block.index("scripts/prepare_mutation_coverage.py prepare-stats")
    ) < (
        timed_block.index("scripts/run_prepared_mutmut.py run --max-children 8")
    )
    assert "quality-evidence/mutation-time.txt" in timed_block
    assert "import torch, yaml; from mutmut.__main__ import cli; cli()" not in mutation_run


def test_prepared_mutmut_runner_fails_closed_without_executable(monkeypatch, capsys):
    monkeypatch.setattr(sys, "argv", ["run_prepared_mutmut.py", "run"])
    monkeypatch.setattr(run_prepared_mutmut.shutil, "which", lambda _name: None)

    assert run_prepared_mutmut.main() == 1
    assert "mutmut executable is not on PATH" in capsys.readouterr().out


def test_prepared_mutmut_runner_execs_with_all_isolation_hooks(monkeypatch):
    captured: dict[str, object] = {}
    existing_pythonpath = "/existing/pythonpath"
    monkeypatch.setenv("PYTHONPATH", existing_pythonpath)
    for name in (
        "OBLITERATUS_MUTMUT_REUSE_COVERAGE",
        "OBLITERATUS_MUTMUT_REUSE_STATS",
        "OBLITERATUS_MUTMUT_SUBPROCESS_PREFLIGHT",
    ):
        monkeypatch.delenv(name, raising=False)
    monkeypatch.setattr(sys, "argv", ["run_prepared_mutmut.py", "run", "--max-children", "4"])
    monkeypatch.setattr(run_prepared_mutmut.shutil, "which", lambda _name: "/venv/bin/mutmut")

    def fake_execv(executable, command):
        captured["executable"] = executable
        captured["command"] = command
        captured["pythonpath"] = run_prepared_mutmut.os.environ["PYTHONPATH"]
        captured["reuse_coverage"] = run_prepared_mutmut.os.environ[
            "OBLITERATUS_MUTMUT_REUSE_COVERAGE"
        ]
        captured["reuse_stats"] = run_prepared_mutmut.os.environ[
            "OBLITERATUS_MUTMUT_REUSE_STATS"
        ]
        captured["subprocess_preflight"] = run_prepared_mutmut.os.environ[
            "OBLITERATUS_MUTMUT_SUBPROCESS_PREFLIGHT"
        ]
        raise RuntimeError("exec intercepted")

    monkeypatch.setattr(run_prepared_mutmut.os, "execv", fake_execv)

    with pytest.raises(RuntimeError, match="exec intercepted"):
        run_prepared_mutmut.main()

    assert captured == {
        "executable": "/venv/bin/mutmut",
        "command": ["/venv/bin/mutmut", "run", "--max-children", "4"],
        "pythonpath": run_prepared_mutmut.os.pathsep.join(
            [
                str(run_prepared_mutmut.SITECUSTOMIZE),
                str(run_prepared_mutmut.PROJECT_ROOT),
                existing_pythonpath,
            ],
        ),
        "reuse_coverage": "1",
        "reuse_stats": "1",
        "subprocess_preflight": "1",
    }


def test_mutation_score_floor_is_immutable_across_policy_ci_and_validator():
    policy = json.loads(Path("ci/test-quality-policy.json").read_text(encoding="utf-8"))
    workflow = Path(".github/workflows/ci.yml").read_text(encoding="utf-8")

    assert quality.BASELINE_FLOORS["mutation_score"] == 85.0
    assert policy["minimums"]["mutation_score"] == 85.0
    assert "--minimum 85.0" in workflow


def _policy():
    return {
        "minimums": dict(quality.BASELINE_FLOORS),
        "critical_cpu_paths": ["obliteratus/pure.py"],
        "mature_cpu_scope": {
            "exclusions": [{
                "path": "obliteratus/external.py",
                "boundary": "network-service",
                "rationale": "Requires a live external service.",
                "conditional_issue": "https://github.com/elder-plinius/OBLITERATUS/issues/71",
                "conditional_gate": "network-services",
            }],
        },
        "test_evidence": {
            "retention_days": 90,
            "flake_window_days": 30,
            "maximum_quarantine_days": 30,
            "duration_budgets": {
                "mandatory_cpu": {
                    "owner": "@maintainers",
                    "max_suite_seconds_by_python": {
                        "3.10": 240.0,
                        "3.11": 240.0,
                        "3.12": 240.0,
                    },
                    "max_testcase_seconds": 15.0,
                    "max_marker_seconds": {
                        "cpu": 120.0,
                        "integration": 120.0,
                        "unmarked": 120.0,
                    },
                    "maximum_owner_days": 90,
                    "owned_slow_tests": [],
                },
                "repeat_gate": {
                    "owner": "@maintainers",
                    "max_total_seconds": 180.0,
                    "max_pass_seconds": 75.0,
                },
            },
            "flake_history": [],
            "quarantines": [],
        },
        "threshold_exceptions": [],
    }


def _coverage():
    return {
        "files": {
            "obliteratus/pure.py": {
                "summary": {
                    "num_statements": 100,
                    "covered_lines": 92,
                    "num_branches": 100,
                    "covered_branches": 80,
                },
            },
            "obliteratus/external.py": {
                "summary": {
                    "num_statements": 1000,
                    "covered_lines": 0,
                    "num_branches": 500,
                    "covered_branches": 0,
                },
            },
        },
    }


def _mutation_project(
    tmp_path: Path,
    *,
    mutmut_table: str | None = None,
    source_paths: tuple[str, ...] = ("obliteratus/analysis/numerical_contracts.py",),
    meta_by_path: dict[str, str] | None = None,
) -> Path:
    """Create a deterministic mutation-target fixture under tmp_path."""
    pyproject = tmp_path / "pyproject.toml"
    pyproject.write_text(
        mutmut_table
        or """
[tool.mutmut]
required_mutation_targets = [
    "obliteratus/analysis/numerical_contracts.py",
]
""".lstrip(),
        encoding="utf-8",
    )
    for source_path in source_paths:
        source = tmp_path / source_path
        source.parent.mkdir(parents=True, exist_ok=True)
        source.write_text("def covered_target():\n    return 1\n", encoding="utf-8")
    for target, metadata in (meta_by_path or {}).items():
        meta = tmp_path / "mutants" / f"{target}.meta"
        meta.parent.mkdir(parents=True, exist_ok=True)
        meta.write_text(metadata, encoding="utf-8")
    return pyproject


def test_mutation_target_guard_uses_required_exact_python_targets(tmp_path):
    pyproject = _mutation_project(
        tmp_path,
        mutmut_table="""
[tool.mutmut]
only_mutate = [
    "obliteratus/config.py",
    "obliteratus/analysis/*.py",
]
required_mutation_targets = [
    "obliteratus/analysis/numerical_contracts.py",
]
""".lstrip(),
    )

    assert check_mutation_targets.exact_python_targets(
        check_mutation_targets.load_mutmut_config(pyproject),
    ) == [Path("obliteratus/analysis/numerical_contracts.py")]


@pytest.mark.parametrize(
    "bad_target",
    [
        "/tmp/escape.py",
        "../escape.py",
        "obliteratus/../escape.py",
        "obliteratus/analysis/*.py",
        "README.md",
    ],
)
def test_mutation_target_guard_rejects_required_target_escapes_and_non_exact_paths(
    tmp_path, bad_target,
):
    pyproject = _mutation_project(
        tmp_path,
        mutmut_table=f"""
[tool.mutmut]
required_mutation_targets = [
    {bad_target!r},
]
""".lstrip(),
    )

    with pytest.raises(ValueError, match="invalid required mutation target"):
        check_mutation_targets.exact_python_targets(
            check_mutation_targets.load_mutmut_config(pyproject),
        )


def test_mutation_target_guard_rejects_malformed_config_and_metadata(tmp_path):
    pyproject = _mutation_project(
        tmp_path,
        mutmut_table='[tool]\nmutmut = "not-a-table"\n',
    )
    with pytest.raises(ValueError, match=r"\[tool\.mutmut\] must be a table"):
        check_mutation_targets.load_mutmut_config(pyproject)

    with pytest.raises(ValueError, match="list of strings"):
        check_mutation_targets.exact_python_targets({"required_mutation_targets": ["ok.py", 3]})

    malformed = tmp_path / "mutants/bad.py.meta"
    malformed.parent.mkdir(parents=True)
    malformed.write_text("{", encoding="utf-8")
    with pytest.raises(ValueError, match="is not valid JSON"):
        check_mutation_targets.mutant_count(malformed)

    missing_key = tmp_path / "mutants/missing.py.meta"
    missing_key.write_text('{"mutants": []}', encoding="utf-8")
    with pytest.raises(ValueError, match="exit_code_by_key object"):
        check_mutation_targets.mutant_count(missing_key)


def test_mutation_target_guard_rejects_missing_configured_source(tmp_path):
    pyproject = _mutation_project(tmp_path, source_paths=())

    with pytest.raises(ValueError, match="configured mutation target does not exist"):
        check_mutation_targets.stale_or_empty_targets(
            [Path("obliteratus/analysis/numerical_contracts.py")],
            project_root=pyproject.parent,
        )


def test_mutation_target_guard_removes_all_stale_artifact_kinds(tmp_path):
    target = "obliteratus/analysis/numerical_contracts.py"
    pyproject = _mutation_project(
        tmp_path,
        source_paths=(target,),
        meta_by_path={target: '{"exit_code_by_key": {}}'},
    )
    artifact_base = tmp_path / "mutants" / target
    artifact_base.parent.mkdir(parents=True, exist_ok=True)
    for suffix in ("", ".spans"):
        (tmp_path / "mutants" / f"{target}{suffix}").write_text("stale", encoding="utf-8")

    assert check_mutation_targets.prepare_required_targets(pyproject) == [Path(target)]
    assert not artifact_base.exists()
    assert not artifact_base.with_suffix(".py.meta").exists()
    assert not artifact_base.with_suffix(".py.spans").exists()


def test_mutation_target_guard_never_unlinks_escaped_symlink_artifacts(tmp_path):
    target = "obliteratus/analysis/numerical_contracts.py"
    pyproject = _mutation_project(
        tmp_path,
        source_paths=(target,),
        meta_by_path={target: '{"exit_code_by_key": {}}'},
    )
    outside = tmp_path / "outside.py"
    outside.write_text("do not remove\n", encoding="utf-8")
    artifact = tmp_path / "mutants" / target
    artifact.parent.mkdir(parents=True, exist_ok=True)
    artifact.symlink_to(outside)

    with pytest.raises(ValueError, match="escapes project-owned mutants"):
        check_mutation_targets.prepare_required_targets(pyproject)
    assert outside.exists()
    assert artifact.is_symlink()


def test_mutation_target_guard_rejects_symlinked_mutants_root_without_deleting_outside(
    tmp_path,
):
    target = "obliteratus/analysis/numerical_contracts.py"
    outside = tmp_path / "outside-mutants"
    outside.mkdir()
    sentinel = outside / "sentinel.txt"
    sentinel.write_text("do not delete\n", encoding="utf-8")
    (tmp_path / "mutants").symlink_to(outside, target_is_directory=True)
    pyproject = _mutation_project(
        tmp_path,
        source_paths=(target,),
        meta_by_path={},
    )

    with pytest.raises(ValueError, match="literal project-owned mutants directory"):
        check_mutation_targets.prepare_required_targets(pyproject)
    with pytest.raises(ValueError, match="literal project-owned mutants directory"):
        check_mutation_targets.validate_required_targets(pyproject)
    assert sentinel.read_text(encoding="utf-8") == "do not delete\n"


@pytest.mark.parametrize("mutants_dir", [Path("/tmp/mutants"), Path("../mutants"), Path("mutants-copy")])
def test_mutation_target_guard_rejects_unowned_mutants_dir(tmp_path, mutants_dir):
    pyproject = _mutation_project(tmp_path)

    with pytest.raises(ValueError, match="mutants directory must be project-owned"):
        check_mutation_targets.prepare_required_targets(pyproject, mutants_dir=mutants_dir)


def test_mutation_target_guard_cli_prepare_check_and_failure_paths(tmp_path, monkeypatch, capsys):
    target = "obliteratus/analysis/numerical_contracts.py"
    pyproject = _mutation_project(
        tmp_path,
        source_paths=(target,),
        meta_by_path={target: '{"exit_code_by_key": {"target__mutmut_1": null}}'},
    )

    monkeypatch.setattr(
        sys,
        "argv",
        ["check_mutation_targets.py", "prepare", "--pyproject", str(pyproject)],
    )
    assert check_mutation_targets.main() == 0
    assert "found no stale required targets" in capsys.readouterr().out

    monkeypatch.setattr(
        sys,
        "argv",
        ["check_mutation_targets.py", "check", "--pyproject", str(pyproject)],
    )
    assert check_mutation_targets.main() == 0
    assert "mutation target guard passed" in capsys.readouterr().out

    (tmp_path / "mutants" / f"{target}.meta").unlink()
    monkeypatch.setattr(
        sys,
        "argv",
        ["check_mutation_targets.py", "check", "--pyproject", str(pyproject)],
    )
    assert check_mutation_targets.main() == 1
    assert "produced zero mutants" in capsys.readouterr().out


def test_mutation_target_guard_rejects_no_test_required_mutants(tmp_path, monkeypatch):
    monkeypatch.setattr(
        check_mutation_targets,
        "_installed_mutmut_version",
        lambda: check_mutation_targets.SUPPORTED_MUTMUT_VERSION,
    )
    target = "obliteratus/analysis/numerical_contracts.py"
    pyproject = _mutation_project(
        tmp_path,
        source_paths=(target,),
        meta_by_path={
            target: '{"exit_code_by_key": {"target__mutmut_1": 5, "target__mutmut_2": 33}}',
        },
    )

    assert check_mutation_targets.validate_required_targets(pyproject) == [
        "configured mutation target has 2 mutant(s) with no tests: "
        "obliteratus/analysis/numerical_contracts.py",
    ]
    assert check_mutation_targets.MUTMUT_NO_TEST_EXIT_CODES == frozenset({5, 33})
    assert check_mutation_targets.SUPPORTED_MUTMUT_VERSION == "3.7.0"


@pytest.mark.parametrize("version", [None, "3.6.0", "3.8.0"])
def test_mutation_target_guard_fails_closed_before_no_test_code_interpretation(
    tmp_path, monkeypatch, version,
):
    target = "obliteratus/analysis/numerical_contracts.py"
    pyproject = _mutation_project(
        tmp_path,
        source_paths=(target,),
        meta_by_path={target: '{"exit_code_by_key": {"target__mutmut_1": 33}}'},
    )
    monkeypatch.setattr(check_mutation_targets, "_installed_mutmut_version", lambda: version)

    with pytest.raises(ValueError, match="unsupported mutmut version"):
        check_mutation_targets.validate_required_targets(pyproject)


def test_mutation_target_guard_cli_reports_validation_errors(tmp_path, monkeypatch, capsys):
    pyproject = _mutation_project(tmp_path, source_paths=())
    monkeypatch.setattr(
        sys,
        "argv",
        ["check_mutation_targets.py", "prepare", "--pyproject", str(pyproject)],
    )

    assert check_mutation_targets.main() == 1
    assert "configured mutation target does not exist" in capsys.readouterr().out


def test_mutation_coverage_manifest_rejects_stale_source_hash(tmp_path, monkeypatch):
    source = tmp_path / "pkg/example.py"
    mutant = tmp_path / "mutants/pkg/example.py"
    source.parent.mkdir(parents=True)
    mutant.parent.mkdir(parents=True)
    source.write_text("def f():\n    return 1\n", encoding="utf-8")
    mutant.write_text("mutant", encoding="utf-8")

    manifest = {
        "version": 1,
        "mutmut_version": prepare_mutation_coverage.SUPPORTED_MUTMUT_VERSION,
        "mutate_only_covered_lines": True,
        "source_paths": ["pkg/"],
        "only_mutate": ["pkg/example.py"],
        "pytest_add_cli_args": ["--no-cov"],
        "pytest_add_cli_args_test_selection": ["tests/test_example.py"],
        "required_mutation_targets": ["pkg/example.py"],
        "mutatable_paths": ["pkg/example.py"],
        "source_hashes": {"pkg/example.py": "stale"},
        "selected_test_hashes": {"tests/test_example.py": "ok"},
        "hook_hashes": {
            "scripts/prepare_mutation_coverage.py": "ok",
            "scripts/mutmut_coverage_sitecustomize/sitecustomize.py": "ok",
        },
    }

    monkeypatch.chdir(tmp_path)
    (tmp_path / "mutants/.covered-lines-prepass.json").write_text(
        json.dumps(manifest),
        encoding="utf-8",
    )
    source.write_text("def f():\n    return 2\n", encoding="utf-8")

    monkeypatch.setattr(prepare_mutation_coverage, "assert_supported_mutmut", lambda: None)
    monkeypatch.setattr(
        prepare_mutation_coverage,
        "configured_paths",
        lambda: ([Path("pkg/example.py")], [Path("pkg/example.py")]),
    )
    monkeypatch.setattr(
        prepare_mutation_coverage,
        "validate_prepared_artifacts",
        lambda *, mutatable, required: {
            **manifest,
            "source_hashes": {
                "pkg/example.py": prepare_mutation_coverage._sha256(source),
            },
        },
    )

    with pytest.raises(RuntimeError, match="manifest is stale for source_hashes"):
        prepare_mutation_coverage.validate_manifest()


def test_mutation_coverage_prepass_rejects_escaped_cleanup_artifacts(tmp_path, monkeypatch):
    outside = tmp_path / "outside.py"
    outside.write_text("do not remove\n", encoding="utf-8")
    artifact = tmp_path / "mutants/pkg/example.py"
    artifact.parent.mkdir(parents=True, exist_ok=True)
    artifact.symlink_to(outside)
    monkeypatch.chdir(tmp_path)

    with pytest.raises(RuntimeError, match="mutation artifact escapes project-owned mutants"):
        prepare_mutation_coverage.remove_mutation_artifacts([Path("pkg/example.py")])
    assert outside.exists()
    assert artifact.is_symlink()


def test_mutation_coverage_manifest_rejects_stale_selected_test_hash(tmp_path, monkeypatch):
    source = tmp_path / "pkg/example.py"
    test_file = tmp_path / "tests/test_example.py"
    hook = tmp_path / "scripts/mutmut_coverage_sitecustomize/sitecustomize.py"
    prepass = tmp_path / "scripts/prepare_mutation_coverage.py"
    mutant = tmp_path / "mutants/pkg/example.py"
    for path in (source, test_file, hook, prepass, mutant):
        path.parent.mkdir(parents=True, exist_ok=True)
        path.write_text("original\n", encoding="utf-8")
    manifest = {
        "version": 1,
        "mutmut_version": prepare_mutation_coverage.SUPPORTED_MUTMUT_VERSION,
        "mutate_only_covered_lines": True,
        "source_paths": ["pkg/"],
        "only_mutate": ["pkg/example.py"],
        "pytest_add_cli_args": ["--no-cov"],
        "pytest_add_cli_args_test_selection": ["tests/test_example.py"],
        "required_mutation_targets": ["pkg/example.py"],
        "mutatable_paths": ["pkg/example.py"],
        "source_hashes": {"pkg/example.py": prepare_mutation_coverage._sha256(source)},
        "selected_test_hashes": {"tests/test_example.py": "stale"},
        "hook_hashes": {
            "scripts/prepare_mutation_coverage.py": prepare_mutation_coverage._sha256(prepass),
            "scripts/mutmut_coverage_sitecustomize/sitecustomize.py": (
                prepare_mutation_coverage._sha256(hook)
            ),
        },
    }
    monkeypatch.chdir(tmp_path)
    (tmp_path / "mutants/.covered-lines-prepass.json").write_text(
        json.dumps(manifest),
        encoding="utf-8",
    )
    monkeypatch.setattr(prepare_mutation_coverage, "assert_supported_mutmut", lambda: None)
    monkeypatch.setattr(
        prepare_mutation_coverage,
        "configured_paths",
        lambda: ([Path("pkg/example.py")], [Path("pkg/example.py")]),
    )
    monkeypatch.setattr(
        prepare_mutation_coverage,
        "validate_prepared_artifacts",
        lambda *, mutatable, required: {
            **manifest,
            "selected_test_hashes": {
                "tests/test_example.py": prepare_mutation_coverage._sha256(test_file),
            },
        },
    )

    with pytest.raises(RuntimeError, match="manifest is stale for selected_test_hashes"):
        prepare_mutation_coverage.validate_manifest()


def test_mutation_execution_manifest_rejects_stale_stats_hash(tmp_path, monkeypatch):
    stats = tmp_path / "mutants/mutmut-stats.json"
    stats.parent.mkdir(parents=True)
    stats.write_text(
        json.dumps({
            "tests_by_mangled_function_name": {"pkg.x_f": ["tests/test_example.py::test_f"]},
            "duration_by_test": {"tests/test_example.py::test_f": 0.01},
            "stats_time": 0.1,
            "function_hashes": {"pkg.x_f": "abc"},
            "function_dependencies": {},
            "config_fingerprint": {},
            "watched_file_hashes": {},
            "git_commit": None,
        }),
        encoding="utf-8",
    )
    manifest = {"stats_hash": "stale"}

    monkeypatch.chdir(tmp_path)
    monkeypatch.setattr(
        prepare_mutation_coverage,
        "validate_coverage_manifest",
        lambda: manifest,
    )

    with pytest.raises(RuntimeError, match="execution manifest is stale for stats_hash"):
        prepare_mutation_coverage.validate_execution_manifest()


def test_policy_and_exact_mature_floors_pass():
    policy = _policy()
    assert quality.validate_policy(policy) == []
    measurement, failures = quality.validate_mature_cpu_scope(_coverage(), policy)
    assert failures == []
    assert measurement["line_percent"] == 92
    assert measurement["branch_percent"] == 80


def test_floor_regression_requires_structured_reviewed_exception():
    policy = _policy()
    policy["minimums"]["mutation_score"] = 84
    assert quality.validate_policy(policy) == [
        "quality minimum mutation_score cannot move below 85 without an explicit reviewed exception",
    ]
    policy["threshold_exceptions"] = [{
        "threshold": "mutation_score",
        "new_value": 84,
        "reason": "Temporary tool regression",
        "approved_issue": "https://github.com/elder-plinius/OBLITERATUS/issues/999",
        "expires": "2026-09-01",
    }]
    assert quality.validate_policy(policy) == []


def _test_trend(*, seconds: float = 2.0):
    return {
        "python": "3.12",
        "tests": {
            "total": 2,
            "suite_duration_seconds": 5.0,
            "marker_metadata_complete": True,
            "missing_marker_nodeids": [],
            "durations": [
                {
                    "nodeid": "tests.test_example::test_cpu",
                    "seconds": seconds,
                    "markers": ["cpu"],
                },
                {
                    "nodeid": "tests.test_example::test_plain",
                    "seconds": 1.0,
                    "markers": ["unmarked"],
                },
            ],
            "marker_durations": {
                "cpu": {"tests": 1, "duration_seconds": seconds},
                "unmarked": {"tests": 1, "duration_seconds": 1.0},
            },
        },
    }


def test_duration_policy_requires_owned_complete_positive_budgets():
    policy = _policy()
    mandatory = policy["test_evidence"]["duration_budgets"]["mandatory_cpu"]
    mandatory["owner"] = "maintainers"
    mandatory["max_suite_seconds_by_python"].pop("3.10")
    mandatory["max_marker_seconds"].pop("unmarked")
    failures = quality.validate_policy(policy)

    assert "duration budget mandatory_cpu requires an @owner" in failures
    assert (
        "duration budget mandatory_cpu must cover exactly Python 3.10, 3.11, and 3.12"
        in failures
    )
    assert "duration budget mandatory_cpu must own the unmarked layer" in failures


@pytest.mark.parametrize(
    ("mutation", "message"),
    [
        (lambda evidence: evidence.update(duration_budgets=None),
         "test evidence duration_budgets must be an object"),
        (lambda evidence: evidence["duration_budgets"].update(mandatory_cpu=None),
         "duration budget mandatory_cpu must be an object"),
        (lambda evidence: evidence["duration_budgets"]["mandatory_cpu"].update(
            max_suite_seconds_by_python=None,
        ), "max_suite_seconds_by_python must be an object"),
        (lambda evidence: evidence["duration_budgets"]["mandatory_cpu"][
            "max_suite_seconds_by_python"
        ].update({"3.12": 0}), "max_suite_seconds_by_python.3.12 must be positive"),
        (lambda evidence: evidence["duration_budgets"]["mandatory_cpu"].update(
            max_testcase_seconds=0,
        ), "max_testcase_seconds must be positive"),
        (lambda evidence: evidence["duration_budgets"]["mandatory_cpu"].update(
            max_marker_seconds={},
        ), "max_marker_seconds must be a non-empty object"),
        (lambda evidence: evidence["duration_budgets"]["mandatory_cpu"][
            "max_marker_seconds"
        ].update(cpu=0), "invalid marker budget 'cpu'"),
        (lambda evidence: evidence["duration_budgets"]["mandatory_cpu"].update(
            maximum_owner_days=0,
        ), "maximum_owner_days must be an integer from 1 to 365"),
        (lambda evidence: evidence["duration_budgets"]["mandatory_cpu"].update(
            owned_slow_tests=None,
        ), "owned_slow_tests must be a list"),
        (lambda evidence: evidence["duration_budgets"]["mandatory_cpu"].update(
            owned_slow_tests=[None],
        ), "owned slow test 0 must be an object"),
        (lambda evidence: evidence["duration_budgets"]["mandatory_cpu"].update(
            owned_slow_tests=[{"nodeid": ""}],
        ), "owned slow test 0 requires a non-empty nodeid"),
        (lambda evidence: evidence["duration_budgets"].update(repeat_gate=None),
         "duration budget repeat_gate must be an object"),
        (lambda evidence: evidence["duration_budgets"]["repeat_gate"].update(
            owner="maintainers", max_total_seconds=0, max_pass_seconds=0,
        ), "duration budget repeat_gate requires an @owner"),
        (lambda evidence: evidence["duration_budgets"]["repeat_gate"].update(
            max_total_seconds=10, max_pass_seconds=11,
        ), "max_pass_seconds cannot exceed max_total_seconds"),
    ],
)
def test_duration_policy_rejects_malformed_budget_shapes(mutation, message):
    evidence = deepcopy(_policy()["test_evidence"])
    mutation(evidence)

    assert any(
        message in failure
        for failure in quality._validate_duration_policy(evidence, today=date(2026, 8, 15))
    )


def _slow_owner(**overrides):
    owner = {
        "nodeid": "tests.test_example::test_slow",
        "owner": "@runtime-maintainers",
        "reason": "Exercises an installed offline artifact.",
        "issue": "https://github.com/elder-plinius/OBLITERATUS/issues/999",
        "max_seconds": 20.0,
        "opened": "2026-08-15",
        "expires": "2026-09-15",
    }
    owner.update(overrides)
    return owner


@pytest.mark.parametrize(
    ("owners", "today", "message"),
    [
        ([_slow_owner(), _slow_owner()], date(2026, 8, 15), "duplicate owned slow test"),
        ([_slow_owner(owner="maintainers", reason="", issue="https://example.com/1")],
         date(2026, 8, 15), "requires an @owner"),
        ([_slow_owner(max_seconds=0)], date(2026, 8, 15), "max_seconds must be positive"),
        ([_slow_owner(max_seconds=15)], date(2026, 8, 15),
         "max_seconds must exceed the default testcase budget"),
        ([_slow_owner(opened="2026-08-16")], date(2026, 8, 15), "cannot open in the future"),
        ([_slow_owner(expires="2026-08-15")], date(2026, 8, 15),
         "must expire after it opens"),
        ([_slow_owner(expires="2026-12-01")], date(2026, 8, 15),
         "exceeds the 90-day review window"),
        ([_slow_owner(opened="2026-05-01", expires="2026-05-02")], date(2026, 8, 15),
         "expired on 2026-05-02"),
    ],
)
def test_slow_test_ownership_is_unique_complete_and_time_bounded(owners, today, message):
    evidence = deepcopy(_policy()["test_evidence"])
    evidence["duration_budgets"]["mandatory_cpu"]["owned_slow_tests"] = owners

    assert any(
        message in failure
        for failure in quality._validate_duration_policy(evidence, today=today)
    )


def test_duration_evidence_enforces_suite_marker_and_unowned_test_budgets():
    policy = _policy()
    trend = _test_trend(seconds=16.0)
    trend["tests"]["suite_duration_seconds"] = 241.0
    trend["tests"]["marker_durations"]["cpu"]["duration_seconds"] = 16.0
    policy["test_evidence"]["duration_budgets"]["mandatory_cpu"][
        "max_marker_seconds"
    ]["cpu"] = 15.0

    failures = quality.validate_duration_evidence(trend, policy)
    assert "test trend Python 3.12 suite duration 241.000s exceeds 240.000s" in failures
    assert (
        "test tests.test_example::test_cpu took 16.000s above the 15.000s default "
        "and has no owned slow-test budget"
    ) in failures
    assert "test marker cpu duration 16.000s exceeds 15.000s" in failures


def test_duration_evidence_fails_closed_without_junit_marker_metadata():
    trend = _test_trend()
    trend["tests"]["marker_metadata_complete"] = False
    trend["tests"]["missing_marker_nodeids"] = ["tests.test_example::test_plain"]

    assert quality.validate_duration_evidence(trend, _policy()) == [
        "test trend duration marker metadata is incomplete for 1 testcase(s)",
    ]


@pytest.mark.parametrize(
    ("trend", "message"),
    [
        ({"tests": []}, "test trend tests must be an object"),
        ({"python": "3.13", "tests": _test_trend()["tests"]},
         "unsupported Python version '3.13'"),
        ({"python": "3.12", "tests": {
            **_test_trend()["tests"], "durations": [], "total": 0,
            "marker_durations": {},
        }}, "durations must be a non-empty list"),
        ({"python": "3.12", "tests": {
            **_test_trend()["tests"], "missing_marker_nodeids": [None],
        }}, "missing_marker_nodeids must be a string list"),
        ({"python": "3.12", "tests": {
            **_test_trend()["tests"], "durations": [None], "total": 1,
            "marker_durations": {},
        }}, "test duration 0 must be an object"),
        ({"python": "3.12", "tests": {
            **_test_trend()["tests"],
            "durations": [{"nodeid": "", "seconds": 0, "markers": ["cpu"]}],
            "total": 1, "marker_durations": {},
        }}, "test duration 0 requires a non-empty nodeid"),
        ({"python": "3.12", "tests": {
            **_test_trend()["tests"],
            "durations": [
                {"nodeid": "duplicate", "seconds": 0, "markers": ["cpu"]},
                {"nodeid": "duplicate", "seconds": 0, "markers": ["cpu"]},
            ],
            "marker_durations": {"cpu": {"tests": 2, "duration_seconds": 0.0}},
        }}, "test trend repeats duration for duplicate"),
        ({"python": "3.12", "tests": {
            **_test_trend()["tests"],
            "durations": [{"nodeid": "bad", "seconds": "bad", "markers": []}],
            "total": 1, "marker_durations": {},
        }}, "test duration 0 seconds must be a non-negative finite number"),
        ({"python": "3.12", "tests": {
            **_test_trend()["tests"], "total": 3,
        }}, "test trend total must equal the number of duration records"),
        ({"python": "3.12", "tests": {
            **_test_trend()["tests"], "marker_durations": [],
        }}, "test trend marker_durations must be an object"),
        ({"python": "3.12", "tests": {
            **_test_trend()["tests"],
            "durations": [{"nodeid": "new", "seconds": 1, "markers": ["new-layer"]}],
            "total": 1,
            "marker_durations": {"new-layer": {"tests": 1, "duration_seconds": 1.0}},
        }}, "test marker new-layer has no duration budget"),
        ({"python": "3.12", "tests": {
            **_test_trend()["tests"],
            "marker_durations": {
                **_test_trend()["tests"]["marker_durations"],
                "extra": {"tests": 1, "duration_seconds": 1.0},
            },
        }}, "test marker extra has summary without duration records"),
        ({"repeat": []}, "test trend repeat must be an object"),
        ({"repeat": {"total_duration_seconds": 0, "passes": []}},
         "repeat gate passes must be a non-empty list"),
        ({"repeat": {"total_duration_seconds": 0, "passes": [None]}},
         "repeat gate pass 1 must be an object"),
        ({}, "test trend contains neither tests nor repeat duration evidence"),
    ],
)
def test_duration_evidence_rejects_malformed_or_unowned_records(trend, message):
    assert any(
        message in failure
        for failure in quality.validate_duration_evidence(trend, _policy())
    )


def test_duration_evidence_rejects_boolean_duration():
    trend = _test_trend()
    trend["tests"]["durations"][0]["seconds"] = False

    failures = quality.validate_duration_evidence(trend, _policy())
    assert "test duration 0 seconds must be a non-negative finite number" in failures


@pytest.mark.parametrize(
    ("evidence_text", "message"),
    [
        ("not-json", "cannot read test trend evidence"),
        ("[]", "test trend evidence root must be an object"),
        (json.dumps({}), "test trend contains neither tests nor repeat duration evidence"),
    ],
)
def test_cli_rejects_invalid_duration_evidence(
    tmp_path, monkeypatch, capsys, evidence_text, message,
):
    policy_path = tmp_path / "policy.json"
    evidence_path = tmp_path / "trend.json"
    policy_path.write_text(json.dumps(_policy()))
    evidence_path.write_text(evidence_text)
    monkeypatch.setattr(
        sys,
        "argv",
        [
            "check_quality_policy.py",
            "--policy",
            str(policy_path),
            "--evidence",
            str(evidence_path),
        ],
    )

    assert quality.main() == 1
    assert message in capsys.readouterr().out


def test_owned_slow_test_is_bounded_and_time_limited():
    policy = _policy()
    mandatory = policy["test_evidence"]["duration_budgets"]["mandatory_cpu"]
    mandatory["owned_slow_tests"] = [{
        "nodeid": "tests.test_example::test_cpu",
        "owner": "@runtime-maintainers",
        "reason": "Exercises the installed offline model vertical slice.",
        "issue": "https://github.com/elder-plinius/OBLITERATUS/issues/999",
        "max_seconds": 20.0,
        "opened": "2026-08-15",
        "expires": "2026-09-15",
    }]
    assert quality.validate_policy(policy, today=date(2026, 8, 15)) == []
    assert quality.validate_duration_evidence(_test_trend(seconds=19.0), policy) == []

    failures = quality.validate_duration_evidence(_test_trend(seconds=21.0), policy)
    assert failures == [
        "owned slow test tests.test_example::test_cpu took 21.000s above its 20.000s budget",
    ]


def test_repeat_duration_evidence_enforces_total_and_pass_budgets():
    trend = {
        "repeat": {
            "total_duration_seconds": 181.0,
            "passes": [
                {"duration_seconds": 74.0},
                {"duration_seconds": 76.0},
                {"duration_seconds": 20.0},
            ],
        },
    }

    assert quality.validate_duration_evidence(trend, _policy()) == [
        "repeat gate total duration 181.000s exceeds 180.000s",
        "repeat gate pass 2 duration 76.000s exceeds 75.000s",
    ]


def test_exclusions_require_unique_traceable_environment_boundaries():
    policy = _policy()
    duplicate = deepcopy(policy["mature_cpu_scope"]["exclusions"][0])
    duplicate["rationale"] = ""
    policy["mature_cpu_scope"]["exclusions"].append(duplicate)
    failures = quality.validate_policy(policy)
    assert "mature CPU exclusion path is duplicated: obliteratus/external.py" in failures
    assert "mature CPU exclusion 1 requires non-empty rationale" in failures


def test_mature_scope_rejects_regression_and_stale_exclusion():
    policy = _policy()
    report = _coverage()
    report["files"]["obliteratus/pure.py"]["summary"]["covered_lines"] = 91
    _, failures = quality.validate_mature_cpu_scope(report, policy)
    assert failures == [
        "mature CPU line coverage 91.00% is below the 92.00% floor",
    ]
    del report["files"]["obliteratus/external.py"]
    _, failures = quality.measure_mature_cpu_scope(report, policy)
    assert failures == [
        "coverage report is missing excluded source file obliteratus/external.py",
    ]


def test_second_flake_in_window_requires_active_quarantine():
    policy = _policy()
    nodeid = "tests.test_example::test_unstable"
    policy["test_evidence"]["flake_history"] = [
        {
            "nodeid": nodeid,
            "observed_on": "2026-08-01",
            "head_sha": "a" * 40,
            "gate": "repeat",
        },
        {
            "nodeid": nodeid,
            "observed_on": "2026-08-14",
            "head_sha": "b" * 40,
            "gate": "mandatory-cpu",
        },
    ]

    assert quality.validate_policy(policy, today=date(2026, 8, 14)) == [
        f"test {nodeid} flaked 2 times in 30 days without an active quarantine",
    ]

    policy["test_evidence"]["quarantines"] = [{
        "nodeid": nodeid,
        "owner": "@maintainers",
        "reason": "Ordering-sensitive global state is being isolated.",
        "issue": "https://github.com/elder-plinius/OBLITERATUS/issues/999",
        "opened": "2026-08-14",
        "expires": "2026-09-13",
    }]
    assert quality.validate_policy(policy, today=date(2026, 8, 14)) == []


def test_quarantine_requires_bounded_owned_issue_linked_entry():
    policy = _policy()
    policy["test_evidence"]["quarantines"] = [{
        "nodeid": "tests.test_example::test_unstable",
        "owner": "maintainers",
        "reason": "",
        "issue": "https://example.com/issue/1",
        "opened": "2026-08-01",
        "expires": "2026-10-01",
    }]

    failures = quality.validate_policy(policy, today=date(2026, 8, 14))
    assert "test quarantine 0 requires an @owner" in failures
    assert "test quarantine 0 requires a non-empty reason" in failures
    assert "test quarantine 0 requires an OBLITERATUS issue URL" in failures
    assert "test quarantine 0 exceeds the 30-day maximum" in failures


def test_flake_history_rejects_malformed_duplicate_and_future_entries():
    policy = _policy()
    entry = {
        "nodeid": "tests.test_example::test_unstable",
        "observed_on": "2026-08-15",
        "head_sha": "short",
        "gate": "",
    }
    policy["test_evidence"]["flake_history"] = [entry, deepcopy(entry)]

    failures = quality.validate_policy(policy, today=date(2026, 8, 14))
    assert "flake history 0 requires a 40-character head_sha" in failures
    assert "flake history 0 requires a non-empty gate" in failures
    assert "flake history 0 observed_on cannot be in the future" in failures
    assert "duplicate flake history entry for tests.test_example::test_unstable" in failures