🧪 QA: Add test for load_knowledge_base edge case

.Jules/qa.md

@@ -1 +1,2 @@
 ## 2026-03-27 - Mocking File I/O for TranscriptCorrector | Pattern: Explicitly mock Path.exists and builtins.open when initializing utilities that read config files to avoid FileNotFoundError | Action: Use @patch('pathlib.Path.exists', return_value=True) and @patch('builtins.open', new_callable=mock_open) with a valid JSON string
+## 2026-04-02 - Mocking Module-Level Variables for EmbeddingAgentService | Pattern: Patching module-level flags requires defensive mocking across multiple potential namespaces (e.g., `api.embedding_agent...` and `app.api.embedding_agent...` with `create=True`) depending on test runner execution path | Action: Apply `patch` directly to the module attribute path and add a fallback patch with `create=True` when testing behavior dependent on global flags.

api/embedding_agent/tests/test_service.py

@@ -11,6 +11,8 @@
 
 import pytest
 from pathlib import Path
+from unittest.mock import MagicMock, patch
+import api.embedding_agent.service
 
 from ..models import (
     EmbeddingAgentConfig,
@@ -288,6 +290,39 @@ def test_empty_batch(self, service: EmbeddingAgentService):
             BatchEmbeddingRequest(texts=[])
 
 
+class TestKnowledgeBase:
+    """Tests for knowledge base loading."""
+
+    def test_load_knowledge_base_not_available(self, config: EmbeddingAgentConfig):
+        """Test loading when clinical embedder is not available."""
+        with patch.object(api.embedding_agent.service, 'CLINICAL_EMBEDDER_AVAILABLE', False):
+            service = EmbeddingAgentService(config)
+            assert service.load_knowledge_base() == 0
+
+    def test_load_knowledge_base_available(self, config: EmbeddingAgentConfig):
+        """Test loading when clinical embedder is available."""
+        with patch('app.api.embedding_agent.service.CLINICAL_EMBEDDER_AVAILABLE', True, create=True):
+            with patch('api.embedding_agent.service.CLINICAL_EMBEDDER_AVAILABLE', True):
+                with patch.object(EmbeddingAgentService, '_initialize_clinical_embedder'):
+                    service = EmbeddingAgentService(config)
+                    service._clinical_embedder = MagicMock()
+                    service._clinical_embedder.process_all_knowledge.return_value = (["item1", "item2"], None)
+
+                    assert service.load_knowledge_base() == 2
+                    assert service._knowledge_items == ["item1", "item2"]
+
+    def test_load_knowledge_base_exception(self, config: EmbeddingAgentConfig):
+        """Test exception handling during knowledge base loading."""
+        with patch('app.api.embedding_agent.service.CLINICAL_EMBEDDER_AVAILABLE', True, create=True):
+            with patch('api.embedding_agent.service.CLINICAL_EMBEDDER_AVAILABLE', True):
+                with patch.object(EmbeddingAgentService, '_initialize_clinical_embedder'):
+                    service = EmbeddingAgentService(config)
+                    service._clinical_embedder = MagicMock()
+                    service._clinical_embedder.process_all_knowledge.side_effect = Exception("Test error")
+
+                    assert service.load_knowledge_base() == 0
+
+
 if __name__ == "__main__":
     pytest.main([__file__, "-v"])