test: cover summary custom instruction clears

tests/test_config_helpers.py

@@ -0,0 +1,51 @@
+from types import SimpleNamespace
+from typing import Any
+
+from src.schemas import MessageConfiguration, SummaryConfiguration
+from src.utils.config_helpers import deep_update, get_configuration
+
+
+def _configured_node(configuration: dict[str, Any]) -> Any:
+    return SimpleNamespace(configuration=configuration)
+
+
+class TestDeepUpdate:
+    def test_summary_custom_instructions_none_clears_inherited_value(self) -> None:
+        base = {
+            "summary": {
+                "enabled": True,
+                "custom_instructions": "Write summaries in German.",
+            }
+        }
+
+        deep_update(
+            base,
+            {"summary": {"enabled": None, "custom_instructions": None}},
+        )
+
+        assert base["summary"]["enabled"] is True
+        assert base["summary"]["custom_instructions"] is None
+
+
+class TestGetConfiguration:
+    def test_session_can_clear_workspace_summary_custom_instructions(self) -> None:
+        workspace = _configured_node(
+            {"summary": {"custom_instructions": "Write summaries in German."}}
+        )
+        session = _configured_node({"summary": {"custom_instructions": None}})
+
+        configuration = get_configuration(None, session, workspace)
+
+        assert configuration.summary.custom_instructions is None
+
+    def test_message_can_clear_session_summary_custom_instructions(self) -> None:
+        session = _configured_node(
+            {"summary": {"custom_instructions": "Write summaries in German."}}
+        )
+        message_configuration = MessageConfiguration(
+            summary=SummaryConfiguration(custom_instructions=None)
+        )
+
+        configuration = get_configuration(message_configuration, session)
+
+        assert configuration.summary.custom_instructions is None