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tests/unit/services/backup/service.py

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+# retoor <retoor@molodetz.nl>
+
+from devplacepy.services.backup import service, store
+
+
+def _stats(used_percent):
+    return {
+        "disk": {
+            "total_bytes": 100,
+            "used_bytes": used_percent,
+            "free_bytes": 100 - used_percent,
+            "total_human": "100 B",
+            "used_human": f"{used_percent} B",
+            "free_human": f"{100 - used_percent} B",
+            "used_percent": used_percent,
+        }
+    }
+
+
+def _disk(used_percent):
+    return _stats(used_percent)["disk"]
+
+
+def test_check_disk_usage_warns_once_and_recovers_once(local_db, monkeypatch):
+    svc = service.BackupService()
+    assert svc.disk_warn_percent_field.default == service.DEFAULT_DISK_WARN_PERCENT
+    logs = []
+    monkeypatch.setattr(svc, "log", lambda message: logs.append(message))
+
+    monkeypatch.setattr(store, "disk_usage", lambda: _disk(50))
+    svc._check_disk_usage()
+    assert logs == []
+    assert svc._disk_warned is False
+
+    monkeypatch.setattr(store, "disk_usage", lambda: _disk(95))
+    svc._check_disk_usage()
+    assert len(logs) == 1
+    assert "critical" in logs[0].lower()
+    assert svc._disk_warned is True
+
+    svc._check_disk_usage()
+    assert len(logs) == 1
+
+    monkeypatch.setattr(store, "disk_usage", lambda: _disk(40))
+    svc._check_disk_usage()
+    assert len(logs) == 2
+    assert "under threshold" in logs[1].lower()
+    assert svc._disk_warned is False
+
+
+def test_collect_metrics_includes_disk_usage_stat(local_db, monkeypatch):
+    svc = service.BackupService()
+    monkeypatch.setattr(store, "disk_usage", lambda: _disk(62))
+
+    metrics = svc.collect_metrics()
+
+    labels = [stat["label"] for stat in metrics["stats"]]
+    assert "Disk usage" in labels
+    disk_stat = next(stat for stat in metrics["stats"] if stat["label"] == "Disk usage")
+    assert "62%" in disk_stat["value"]
+
+
+def test_collect_metrics_never_walks_storage_tree(local_db, monkeypatch):
+    svc = service.BackupService()
+    monkeypatch.setattr(store, "disk_usage", lambda: _disk(10))
+
+    def boom():
+        raise AssertionError("compute_storage_stats must not run on the service tick")
+
+    monkeypatch.setattr(store, "compute_storage_stats", boom)
+    svc.collect_metrics()
+    svc._check_disk_usage()