Refactor: Move backend files to backend/ directory and split .gitignore

backend/tests/test_summarizer.py

@@ -0,0 +1,48 @@
+import pytest
+from unittest.mock import MagicMock, patch
+from langchain_core.messages import AIMessage
+from ea_chatbot.graph.nodes.summarizer import summarizer_node
+from ea_chatbot.graph.state import AgentState
+
+@pytest.fixture
+def mock_llm():
+    with patch("ea_chatbot.graph.nodes.summarizer.get_llm_model") as mock_get_llm:
+        mock_llm_instance = MagicMock()
+        mock_get_llm.return_value = mock_llm_instance
+        yield mock_llm_instance
+
+def test_summarizer_node_success(mock_llm):
+    """Test that summarizer_node invokes LLM with correct inputs and returns messages."""
+    state = {
+        "question": "What is the total count?",
+        "plan": "1. Run query\n2. Sum results",
+        "code_output": "The total is 100",
+        "messages": []
+    }
+    
+    mock_llm.invoke.return_value = AIMessage(content="The final answer is 100.")
+    
+    result = summarizer_node(state)
+    
+    # Verify LLM was called
+    assert mock_llm.invoke.called
+    
+    # Verify result structure
+    assert "messages" in result
+    assert len(result["messages"]) == 1
+    assert isinstance(result["messages"][0], AIMessage)
+    assert result["messages"][0].content == "The final answer is 100."
+
+def test_summarizer_node_empty_state(mock_llm):
+    """Test handling of empty or minimal state."""
+    state = {
+        "question": "Empty?",
+        "messages": []
+    }
+    
+    mock_llm.invoke.return_value = AIMessage(content="No data provided.")
+    
+    result = summarizer_node(state)
+    
+    assert "messages" in result
+    assert result["messages"][0].content == "No data provided."