test(i18n): guard issue-277 artifact determinism

docs/ISSUE-277-SHARED-I18N-PARITY-ARTIFACT.md

@@ -76,4 +76,5 @@ Status: **Shared locale matrix is aligned (`en`, `da`) and backend→frontend er
 ```bash
 python3 scripts/check_i18n_drift.py
 python3 scripts/report_i18n_parity.py
+python3 scripts/check_i18n_parity_artifact.py
 ```

scripts/check_i18n_parity_artifact.py

@@ -0,0 +1,36 @@
+#!/usr/bin/env python3
+"""Guard issue #277 parity artifact against non-deterministic regeneration."""
+
+from __future__ import annotations
+
+import hashlib
+import subprocess
+import sys
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).resolve().parents[1]
+ARTIFACT_PATH = REPO_ROOT / "docs" / "ISSUE-277-SHARED-I18N-PARITY-ARTIFACT.md"
+REPORT_SCRIPT = REPO_ROOT / "scripts" / "report_i18n_parity.py"
+
+
+def sha256(path: Path) -> str:
+    return hashlib.sha256(path.read_bytes()).hexdigest()
+
+
+def main() -> int:
+    before = sha256(ARTIFACT_PATH)
+
+    for run in range(1, 3):
+        subprocess.run([sys.executable, str(REPORT_SCRIPT)], cwd=REPO_ROOT, check=True)
+        after = sha256(ARTIFACT_PATH)
+        if after != before:
+            raise SystemExit(
+                f"issue #277 parity artifact is not deterministic after run {run}: {before} != {after}"
+            )
+
+    print(f"issue #277 parity artifact deterministic: {before}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

scripts/report_i18n_parity.py

@@ -179,6 +179,7 @@ def render_report(catalog: dict) -> str:
     lines.append("```bash")
     lines.append("python3 scripts/check_i18n_drift.py")
     lines.append("python3 scripts/report_i18n_parity.py")
+    lines.append("python3 scripts/check_i18n_parity_artifact.py")
     lines.append("```")
     lines.append("")
     return "\n".join(lines)