feat(event_bus): add payload_if_entered_folder predicate with unit tests

surfsense_backend/tests/unit/event_bus/test_entered_folder_predicate.py

@@ -0,0 +1,58 @@
+"""payload_if_entered_folder: decides whether a document commit warrants an event."""
+
+from __future__ import annotations
+
+from typing import Any
+
+import pytest
+
+from app.event_bus.events.document_entered_folder import payload_if_entered_folder
+
+pytestmark = pytest.mark.unit
+
+
+def _call(**overrides: Any) -> dict[str, Any] | None:
+    defaults: dict[str, Any] = {
+        "document_id": 1,
+        "search_space_id": 10,
+        "new_folder_id": 7,
+        "previous_folder_id": None,
+        "folder_id_changed": True,
+        "status_state": "ready",
+        "document_type": "FILE",
+        "title": "report.pdf",
+        "connector_id": None,
+        "created_by_id": None,
+    }
+    defaults.update(overrides)
+    return payload_if_entered_folder(**defaults)
+
+
+def test_folder_set_ready_fires() -> None:
+    result = _call()
+
+    assert result is not None
+    assert result["event_type"] == "document.entered_folder"
+    assert result["search_space_id"] == 10
+    assert result["payload"]["folder_id"] == 7
+    assert result["payload"]["previous_folder_id"] is None
+
+
+def test_no_folder_is_silent() -> None:
+    assert _call(new_folder_id=None) is None
+
+
+def test_not_ready_is_silent() -> None:
+    assert _call(status_state="processing") is None
+
+
+def test_folder_unchanged_is_silent() -> None:
+    assert _call(folder_id_changed=False) is None
+
+
+def test_move_carries_previous_folder_id() -> None:
+    result = _call(previous_folder_id=3, new_folder_id=7)
+
+    assert result is not None
+    assert result["payload"]["previous_folder_id"] == 3
+    assert result["payload"]["folder_id"] == 7