fix(ci): sanitize diagnostics fail-closed and purge malformed trace records

.github/scripts/verify_sanitized_artifacts.py

@@ -0,0 +1,206 @@
+#!/usr/bin/env python3
+"""Fail-closed independent verification and sanitization gate for test diagnostics.
+
+Runs after test suite completion or abnormal runner termination (e.g. failures, timeouts, crashes).
+Ensures that no unsanitized traces, raw credentials, temporary archives, or unauthorized
+diagnostics can ever be published as CI artifacts, while preserving safe JUnit XML reporting.
+"""
+from __future__ import annotations
+
+import argparse
+import json
+import logging
+import os
+import sys
+import tempfile
+import xml.etree.ElementTree as ET
+from pathlib import Path
+
+# Add repository root to Python path to import sanitizer
+REPO_ROOT = Path(__file__).resolve().parents[2]
+if str(REPO_ROOT) not in sys.path:
+    sys.path.insert(0, str(REPO_ROOT))
+
+try:
+    from scripts.sanitize_trace_artifacts import sanitize_trace_archive
+except ImportError:
+    # If import fails, define fail-closed fallback
+    def sanitize_trace_archive(zp: str) -> bool:
+        if os.path.exists(zp):
+            try:
+                os.remove(zp)
+            except OSError:
+                pass
+        return False
+
+logging.basicConfig(level=logging.INFO, format="%(levelname)s: %(message)s")
+logger = logging.getLogger("verify_sanitized_artifacts")
+
+PNG_MAGIC = b"\x89PNG\r\n\x1a\n"
+
+
+def is_valid_disposable_ci_fixture() -> bool:
+    """Verify that execution ran inside an authorized disposable synthetic fixture."""
+    is_ci = bool(os.environ.get("CI") or os.environ.get("GITHUB_ACTIONS"))
+    if not is_ci:
+        # Local runs require explicit trace opt-in
+        trace_opt_in = os.environ.get("PLAYWRIGHT_ENABLE_TRACE", "").lower() in ("1", "true")
+        return trace_opt_in
+
+    if os.environ.get("ODYSSEUS_E2E_DISPOSABLE_ARTIFACTS") != "1":
+        return False
+    if os.environ.get("PHOTO_EDITOR_E2E_AUTH") == "0":
+        return False
+
+    data_dir = os.environ.get("PHOTO_EDITOR_E2E_DATA_DIR")
+    if not data_dir:
+        return False
+    resolved = os.path.abspath(data_dir)
+    base_name = os.path.basename(resolved)
+    if not base_name.startswith("odysseus-photo-editor-e2e-"):
+        return False
+
+    allowed_tmp = [os.path.abspath(p) for p in (tempfile.gettempdir(), "/tmp", "/var/tmp")]
+    if not any(resolved.startswith(b + os.sep) or resolved == b for b in allowed_tmp):
+        return False
+
+    db_path = os.environ.get("PHOTO_EDITOR_E2E_DB_PATH")
+    if db_path != os.path.join(resolved, "app.db"):
+        return False
+
+    marker_path = os.path.join(resolved, ".disposable-ci-fixture.json")
+    if not os.path.exists(marker_path):
+        return False
+
+    try:
+        with open(marker_path, "r", encoding="utf-8") as f:
+            fixture = json.load(f)
+            return (
+                fixture.get("synthetic") is True
+                and fixture.get("authenticated") is True
+                and fixture.get("database") == os.path.join(resolved, "app.db")
+            )
+    except Exception:
+        return False
+
+
+def verify_and_sanitize_artifacts(target_dir: str) -> bool:
+    """Independently verify and sanitize diagnostics fail-closed, preserving safe JUnit XML.
+
+    Returns True if verification succeeded, False if fail-closed purge was required.
+    """
+    if not os.path.exists(target_dir):
+        logger.info("Target directory %s does not exist; nothing to sanitize.", target_dir)
+        return True
+
+    disposable_ci = is_valid_disposable_ci_fixture()
+    preserved_xmls = 0
+    sanitized_archives = 0
+    purged_files = 0
+
+    try:
+        for root, _, files in os.walk(target_dir):
+            for filename in files:
+                filepath = os.path.join(root, filename)
+                name_lower = filename.lower()
+
+                # 1. Safe JUnit reporting: preserve valid XML reports
+                if name_lower.endswith(".xml"):
+                    try:
+                        ET.parse(filepath)
+                        preserved_xmls += 1
+                        continue
+                    except Exception as exc:
+                        logger.warning("Corrupted XML report %s: %s; purging fail-closed", filepath, exc)
+                        try:
+                            os.remove(filepath)
+                            purged_files += 1
+                        except OSError:
+                            pass
+                        continue
+
+                # 2. Check if diagnostics are authorized (disposable synthetic fixture)
+                if not disposable_ci:
+                    # In CI without disposable fixture, or local without opt-in: purge all diagnostics
+                    logger.info("Purging diagnostic artifact %s (disposable CI fixture not verified)", filepath)
+                    try:
+                        os.remove(filepath)
+                        purged_files += 1
+                    except OSError:
+                        pass
+                    continue
+
+                # 3. Disposable CI is authorized: enforce strict sanitization
+                if name_lower.endswith(".zip"):
+                    ok = sanitize_trace_archive(filepath)
+                    if ok and os.path.exists(filepath):
+                        sanitized_archives += 1
+                    else:
+                        logger.warning("Trace archive %s failed sanitization; purged fail-closed", filepath)
+                        if os.path.exists(filepath):
+                            try:
+                                os.remove(filepath)
+                            except OSError:
+                                pass
+                        purged_files += 1
+
+                elif name_lower.endswith(".png"):
+                    # Validate PNG magic bytes to ensure not a secret payload disguised as an image
+                    try:
+                        with open(filepath, "rb") as pf:
+                            header = pf.read(8)
+                            if header == PNG_MAGIC:
+                                continue
+                    except Exception:
+                        pass
+                    logger.warning("Invalid or suspicious screenshot %s; purged fail-closed", filepath)
+                    try:
+                        os.remove(filepath)
+                        purged_files += 1
+                    except OSError:
+                        pass
+
+                else:
+                    # Purge any .tmp, .har, .db, .sqlite, .log or unrecognized files
+                    logger.info("Purging unauthorized diagnostic file %s", filepath)
+                    try:
+                        os.remove(filepath)
+                        purged_files += 1
+                    except OSError:
+                        pass
+
+        logger.info(
+            "Artifact verification complete for %s: preserved %d XML reports, sanitized %d archives, purged %d files.",
+            target_dir,
+            preserved_xmls,
+            sanitized_archives,
+            purged_files,
+        )
+        return True
+
+    except Exception as exc:
+        logger.error("Unexpected error during artifact verification: %s; purging all non-XML files fail-closed", exc)
+        try:
+            for p in Path(target_dir).rglob("*"):
+                if p.is_file() and not p.name.lower().endswith(".xml"):
+                    try:
+                        p.unlink(missing_ok=True)
+                    except OSError:
+                        pass
+        except Exception:
+            pass
+        return False
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("target_dir", nargs="?", default="test-results", help="Directory containing test results")
+    args = parser.parse_args()
+
+    ok = verify_and_sanitize_artifacts(args.target_dir)
+    # Always exit 0 so upload-artifact can safely publish verified reports
+    sys.exit(0 if ok else 0)
+
+
+if __name__ == "__main__":
+    main()

.github/workflows/native-test-suites.yml

@@ -39,6 +39,10 @@ jobs:
         run: |
           node .github/scripts/run_native_tests.mjs
           python .github/scripts/check_test_execution.py test-results/native-node/junit.xml --minimum 43
+      - name: Verify and sanitize native test results fail-closed
+        if: always()
+        run: |
+          python .github/scripts/verify_sanitized_artifacts.py test-results/native-node/
       - name: Save native test identities and results
         if: always()
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
@@ -95,6 +99,10 @@ jobs:
         run: |
           npm run test:photo-editor -- --reporter=line,junit
           python .github/scripts/check_test_execution.py test-results/browser-junit.xml --minimum 137
+      - name: Verify and sanitize failure diagnostics fail-closed
+        if: always()
+        run: |
+          python .github/scripts/verify_sanitized_artifacts.py test-results/
       - name: Save per-test results and sanitized failure diagnostics
         if: always()
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1

docs/maintainers/native-test-coverage.md

@@ -25,6 +25,10 @@ Default CI trace suppression remains intact. Only this job's explicit opt-in plu
 a newly generated authenticated synthetic fixture marker permits failure traces.
 The existing structured sanitizer runs before artifacts are uploaded; invalid
 ownership, failed sanitization and missing tooling purge sensitive artifacts.
+Unsupported or malformed sensitive records cause the affected archive to be removed
+fail-closed. An independent fail-closed verification step (.github/scripts/verify_sanitized_artifacts.py)
+runs after test suite execution or abnormal runner termination to prevent publishing
+unsanitized diagnostics while preserving safe JUnit reporting.
 Never upload the fixture directory, database or browser storage state.
 
 The stroke budget now excludes measured synthetic event-delivery pacing and also

scripts/sanitize_trace_artifacts.py

@@ -77,13 +77,14 @@ def sanitize_body_text(text: str) -> str:
 
     # 1. Try JSON
     trimmed = text.strip()
-    if (trimmed.startswith("{") and trimmed.endswith("}")) or (trimmed.startswith("[") and trimmed.endswith("]")):
+    if trimmed.startswith(("{", "[")):
         try:
             parsed = json.loads(trimmed)
             sanitized = sanitize_structured_obj(parsed)
             return json.dumps(sanitized, ensure_ascii=False)
-        except Exception:
-            pass
+        except Exception as exc:
+            if SENSITIVE_KEY_PATTERN.search(trimmed) or any(p in trimmed.lower() for p in SENSITIVE_PARAM_NAMES):
+                raise ValueError(f"Malformed sensitive JSON request body: {exc}") from exc
 
     # 2. Try URL-encoded form data
     if "=" in trimmed and not trimmed.startswith("<"):
@@ -98,8 +99,13 @@ def sanitize_body_text(text: str) -> str:
                     else:
                         out_pairs.append((k, v))
                 return urllib.parse.urlencode(out_pairs)
-        except Exception:
-            pass
+        except Exception as exc:
+            if SENSITIVE_KEY_PATTERN.search(trimmed):
+                raise ValueError(f"Malformed sensitive form request body: {exc}") from exc
+
+    # If unparsed body text contains sensitive keys or tokens, fail closed
+    if SENSITIVE_KEY_PATTERN.search(trimmed) or any(p in trimmed.lower() for p in SENSITIVE_PARAM_NAMES):
+        raise ValueError("Malformed or unsupported sensitive request body in trace entry")
 
     return text
 
@@ -207,7 +213,11 @@ def sanitize_structured_obj(obj: Any) -> Any:
 
 
 def sanitize_jsonl_content(data: bytes) -> bytes:
-    """Sanitize newline-delimited JSON Lines (.trace, .network, .stacks)."""
+    """Sanitize newline-delimited JSON Lines (.trace, .network, .stacks).
+    
+    If any non-empty record cannot be decoded as valid UTF-8 or parsed as valid JSON,
+    or is malformed, raise ValueError fail-closed so the affected archive is permanently removed.
+    """
     lines = data.split(b"\n")
     out_lines = []
     for line in lines:
@@ -216,10 +226,8 @@ def sanitize_jsonl_content(data: bytes) -> bytes:
             continue
         try:
             parsed = json.loads(line.decode("utf-8"))
-        except (json.JSONDecodeError, UnicodeDecodeError):
-            # Not valid JSON, keep as-is
-            out_lines.append(line)
-            continue
+        except (json.JSONDecodeError, UnicodeDecodeError) as err:
+            raise ValueError(f"Malformed or unsupported JSONL trace record: {err}")
         sanitized = sanitize_structured_obj(parsed)
         out_lines.append(json.dumps(sanitized, ensure_ascii=False).encode("utf-8"))
     return b"\n".join(out_lines)
@@ -275,11 +283,10 @@ def sanitize_trace_archive(zp: str) -> bool:
                     elif filename_lower.endswith((".json", ".har")):
                         try:
                             parsed = json.loads(content.decode("utf-8"))
-                            sanitized = sanitize_structured_obj(parsed)
-                            zout.writestr(item, json.dumps(sanitized, ensure_ascii=False).encode("utf-8"))
-                        except Exception:
-                            # If invalid JSON, treat as text line-by-line
-                            zout.writestr(item, sanitize_jsonl_content(content))
+                        except (json.JSONDecodeError, UnicodeDecodeError) as exc:
+                            raise ValueError(f"Malformed JSON in archive member {item.filename}: {exc}") from exc
+                        sanitized = sanitize_structured_obj(parsed)
+                        zout.writestr(item, json.dumps(sanitized, ensure_ascii=False).encode("utf-8"))
                     else:
                         # Unknown binary or text member: exclude to fail closed
                         continue

tests/test_trace_artifact_sanitizer.py

@@ -242,3 +242,72 @@ def test_multiple_trace_archives_in_directory(tmp_path):
     with zipfile.ZipFile(z2, "r") as z:
         content = json.loads(z.read("0.trace").decode().strip())
         assert content["params"]["value"] == "[REDACTED]"
+
+
+def test_fail_closed_malformed_jsonl_record(tmp_path):
+    """Malformed JSONL lines in .trace archives fail closed and delete the archive."""
+    zp = str(tmp_path / "malformed_jsonl.zip")
+    with zipfile.ZipFile(zp, "w") as z:
+        z.writestr(
+            "0-trace.trace",
+            b'{"type": "action", "params": {"value": "secret123"}}\n'
+            b'this is invalid json {"password": "leak_raw_pass"}\n'
+        )
+    ok = sanitize_trace_archive(zp)
+    assert ok is False
+    assert not os.path.exists(zp)
+    assert not os.path.exists(zp + ".tmp")
+
+
+def test_fail_closed_malformed_jsonl_truncated(tmp_path):
+    """Truncated JSONL records in .network archives fail closed and delete the archive."""
+    zp = str(tmp_path / "truncated_jsonl.zip")
+    with zipfile.ZipFile(zp, "w") as z:
+        z.writestr(
+            "0-trace.network",
+            b'{"type": "request", "request": {"url": "https://example.com/api/auth", "headers": [{"name": "Authorization", "value": "Bearer secret_tok"'
+        )
+    ok = sanitize_trace_archive(zp)
+    assert ok is False
+    assert not os.path.exists(zp)
+    assert not os.path.exists(zp + ".tmp")
+
+
+def test_fail_closed_malformed_sensitive_body(tmp_path):
+    """Malformed sensitive request body in trace archives fails closed and deletes archive."""
+    zp = str(tmp_path / "malformed_sensitive_body.zip")
+    with zipfile.ZipFile(zp, "w") as z:
+        record = {
+            "type": "request",
+            "request": {
+                "url": "https://example.com/api/login",
+                "postData": '{"password": "super_secret_pw", "corrupt_trailing": ',
+            },
+        }
+        z.writestr("0-trace.network", json.dumps(record).encode() + b"\n")
+    ok = sanitize_trace_archive(zp)
+    assert ok is False
+    assert not os.path.exists(zp)
+    assert not os.path.exists(zp + ".tmp")
+
+
+def test_fail_closed_malformed_har_member(tmp_path):
+    """Malformed JSON in .har archives fails closed and deletes the archive."""
+    zp = str(tmp_path / "malformed_har.zip")
+    with zipfile.ZipFile(zp, "w") as z:
+        z.writestr("network.har", b'{"log": {"entries": [ malformed JSON content')
+    ok = sanitize_trace_archive(zp)
+    assert ok is False
+    assert not os.path.exists(zp)
+    assert not os.path.exists(zp + ".tmp")
+
+
+def test_fail_closed_invalid_utf8_jsonl_record(tmp_path):
+    """Non-UTF8 byte sequences in JSONL trace records fail closed and delete the archive."""
+    zp = str(tmp_path / "invalid_utf8.zip")
+    with zipfile.ZipFile(zp, "w") as z:
+        z.writestr("0-trace.trace", b"\xff\xfe\x00\x00 invalid utf8 raw bytes\n")
+    ok = sanitize_trace_archive(zp)
+    assert ok is False
+    assert not os.path.exists(zp)
+    assert not os.path.exists(zp + ".tmp")

tests/test_verify_sanitized_artifacts.py

@@ -0,0 +1,209 @@
+"""Tests for the fail-closed artifact verification step (.github/scripts/verify_sanitized_artifacts.py).
+
+Validates that:
+1. Safe JUnit XML reporting is preserved across all scenarios.
+2. Abnormal runner termination without verified disposable CI fixture purges all diagnostics.
+3. Valid disposable CI environments sanitize trace archives fail-closed.
+4. Malformed trace archives are deleted fail-closed without corrupting or deleting JUnit XML reports.
+5. In-progress temporary files, HAR files, and database dumps are purged unconditionally.
+6. Top-level exceptions fail closed to purge all non-XML diagnostics.
+"""
+from __future__ import annotations
+
+import json
+import os
+import subprocess
+import sys
+import tempfile
+import zipfile
+from pathlib import Path
+
+import pytest
+
+REPO_ROOT = Path(__file__).resolve().parents[1]
+VERIFY_SCRIPT = REPO_ROOT / ".github" / "scripts" / "verify_sanitized_artifacts.py"
+
+import importlib.util
+
+spec = importlib.util.spec_from_file_location("verify_sanitized_artifacts", str(VERIFY_SCRIPT))
+verify_module = importlib.util.module_from_spec(spec)
+sys.modules["verify_sanitized_artifacts"] = verify_module
+spec.loader.exec_module(verify_module)
+
+is_valid_disposable_ci_fixture = verify_module.is_valid_disposable_ci_fixture
+verify_and_sanitize_artifacts = verify_module.verify_and_sanitize_artifacts
+
+
+def _setup_disposable_ci(tmp_path: Path) -> dict[str, str]:
+    data_dir = tmp_path / "odysseus-photo-editor-e2e-fixture"
+    data_dir.mkdir(parents=True, exist_ok=True)
+    db_path = data_dir / "app.db"
+    db_path.write_bytes(b"SQLite format 3\x00")
+    marker_file = data_dir / ".disposable-ci-fixture.json"
+    marker_file.write_text(
+        json.dumps({
+            "synthetic": True,
+            "authenticated": True,
+            "database": str(db_path),
+        })
+    )
+    return {
+        "CI": "true",
+        "GITHUB_ACTIONS": "true",
+        "ODYSSEUS_E2E_DISPOSABLE_ARTIFACTS": "1",
+        "PHOTO_EDITOR_E2E_DATA_DIR": str(data_dir),
+        "PHOTO_EDITOR_E2E_DB_PATH": str(db_path),
+        "PHOTO_EDITOR_E2E_AUTH": "1",
+        "ODYSSEUS_TEST_PYTHON": sys.executable,
+    }
+
+
+def test_preserves_valid_junit_xml_cleanly(tmp_path):
+    """Valid JUnit XML files are preserved intact."""
+    results_dir = tmp_path / "test-results"
+    results_dir.mkdir()
+    junit = results_dir / "browser-junit.xml"
+    junit.write_text('<testsuites><testsuite name="photo-editor" tests="137" failures="0"/></testsuites>')
+
+    ok = verify_and_sanitize_artifacts(str(results_dir))
+    assert ok is True
+    assert junit.exists()
+    assert "tests=\"137\"" in junit.read_text()
+
+
+def test_fail_closed_abnormal_termination_purges_all_diagnostics(tmp_path, monkeypatch):
+    """Abnormal runner termination without disposable fixture purges all diagnostics, keeping JUnit."""
+    # Simulate CI without disposable fixture
+    monkeypatch.setenv("CI", "true")
+    monkeypatch.setenv("GITHUB_ACTIONS", "true")
+    monkeypatch.delenv("ODYSSEUS_E2E_DISPOSABLE_ARTIFACTS", raising=False)
+    monkeypatch.delenv("PHOTO_EDITOR_E2E_DATA_DIR", raising=False)
+
+    results_dir = tmp_path / "test-results"
+    results_dir.mkdir()
+    junit = results_dir / "browser-junit.xml"
+    junit.write_text('<testsuites><testsuite name="photo-editor" tests="10" failures="1"/></testsuites>')
+
+    trace = results_dir / "trace.zip"
+    trace.write_bytes(b"PK0304 sensitive trace archive")
+    har = results_dir / "session.har"
+    har.write_text('{"log": {"entries": ["secret"]}}')
+    png = results_dir / "failure.png"
+    png.write_bytes(b"\x89PNG\r\n\x1a\nfake screenshot")
+    tmp = results_dir / "temp.tmp"
+    tmp.write_text("in-progress trace")
+    db = results_dir / "app.db"
+    db.write_bytes(b"SQLite format 3 database")
+
+    ok = verify_and_sanitize_artifacts(str(results_dir))
+    assert ok is True
+
+    # Safe JUnit reporting MUST be preserved
+    assert junit.exists()
+    assert "failures=\"1\"" in junit.read_text()
+
+    # All sensitive diagnostics MUST be purged
+    assert not trace.exists()
+    assert not har.exists()
+    assert not png.exists()
+    assert not tmp.exists()
+    assert not db.exists()
+
+
+def test_sanitizes_trace_archive_when_disposable_ci_verified(tmp_path, monkeypatch):
+    """When running inside a verified disposable CI fixture, trace archives are sanitized fail-closed."""
+    env = _setup_disposable_ci(tmp_path)
+    for k, v in env.items():
+        monkeypatch.setenv(k, v)
+
+    results_dir = tmp_path / "test-results"
+    results_dir.mkdir()
+    junit = results_dir / "browser-junit.xml"
+    junit.write_text('<testsuites><testsuite name="photo-editor" tests="137" failures="0"/></testsuites>')
+
+    trace = results_dir / "trace.zip"
+    with zipfile.ZipFile(trace, "w") as z:
+        action = {"type": "action", "name": "fill", "params": {"value": "super_secret_password"}}
+        z.writestr("0-trace.trace", json.dumps(action).encode() + b"\n")
+
+    png = results_dir / "failure.png"
+    png.write_bytes(b"\x89PNG\r\n\x1a\nvalid screenshot payload")
+
+    ok = verify_and_sanitize_artifacts(str(results_dir))
+    assert ok is True
+
+    assert junit.exists()
+    assert trace.exists()
+    assert png.exists()
+
+    with zipfile.ZipFile(trace, "r") as z:
+        content = json.loads(z.read("0-trace.trace").decode().strip())
+        assert content["params"]["value"] == "[REDACTED]"
+
+
+def test_malformed_trace_archive_purged_preserving_junit_xml(tmp_path, monkeypatch):
+    """Malformed trace archive is purged fail-closed without affecting JUnit XML."""
+    env = _setup_disposable_ci(tmp_path)
+    for k, v in env.items():
+        monkeypatch.setenv(k, v)
+
+    results_dir = tmp_path / "test-results"
+    results_dir.mkdir()
+    junit = results_dir / "browser-junit.xml"
+    junit.write_text('<testsuites><testsuite name="photo-editor" tests="137" failures="1"/></testsuites>')
+
+    # Create trace archive with malformed JSONL line
+    malformed_trace = results_dir / "trace.zip"
+    with zipfile.ZipFile(malformed_trace, "w") as z:
+        z.writestr("0-trace.trace", b'{"type": "action"}\nmalformed not json line\n')
+
+    ok = verify_and_sanitize_artifacts(str(results_dir))
+    assert ok is True
+
+    # JUnit XML is preserved
+    assert junit.exists()
+    # Malformed archive is purged!
+    assert not malformed_trace.exists()
+
+
+def test_unhandled_exception_fails_closed_purges_all_non_xml(tmp_path, monkeypatch):
+    """Unexpected exception during verification triggers emergency fail-closed purge of non-XML files."""
+    env = _setup_disposable_ci(tmp_path)
+    for k, v in env.items():
+        monkeypatch.setenv(k, v)
+
+    results_dir = tmp_path / "test-results"
+    results_dir.mkdir()
+    junit = results_dir / "browser-junit.xml"
+    junit.write_text('<testsuites><testsuite name="photo-editor" tests="137" failures="0"/></testsuites>')
+
+    trace = results_dir / "trace.zip"
+    trace.write_bytes(b"PK0304 trace")
+
+    def broken_sanitize(zp):
+        raise RuntimeError("Simulated unexpected crash in sanitizer")
+
+    monkeypatch.setattr(verify_module, "sanitize_trace_archive", broken_sanitize)
+
+    ok = verify_and_sanitize_artifacts(str(results_dir))
+    assert ok is False
+    # Safe JUnit reporting is preserved
+    assert junit.exists()
+    # Sensitive non-XML file is purged fail-closed!
+    assert not trace.exists()
+
+
+def test_cli_invocation_returns_cleanly(tmp_path):
+    """Running the script as a CLI entrypoint succeeds with exit code 0."""
+    results_dir = tmp_path / "test-results"
+    results_dir.mkdir()
+    junit = results_dir / "junit.xml"
+    junit.write_text('<testsuites><testsuite name="native-node" tests="43" failures="0"/></testsuites>')
+
+    res = subprocess.run(
+        [sys.executable, str(VERIFY_SCRIPT), str(results_dir)],
+        capture_output=True,
+        text=True,
+    )
+    assert res.returncode == 0
+    assert junit.exists()