Add ChatMessageHistory feature for multi-round dialogues in REST sessions (Issue #2284)

Co-Authored-By: Joe Moura <joao@crewai.com>

tests/memory/chat_message_history_test.py

@@ -0,0 +1,151 @@
+import pytest
+from datetime import datetime
+
+from crewai.memory.chat_history.chat_message_history import ChatMessageHistory
+from crewai.memory.chat_history.chat_message import ChatMessage, MessageRole
+
+
+@pytest.fixture
+def chat_message_history():
+    """Fixture to create a ChatMessageHistory instance"""
+    return ChatMessageHistory()
+
+
+def test_add_and_get_messages(chat_message_history):
+    """Test adding messages and retrieving them."""
+    # Add messages
+    chat_message_history.add_human_message("Hello, how are you?")
+    chat_message_history.add_ai_message("I'm doing well, thank you!")
+    chat_message_history.add_system_message("System message")
+    
+    # Get messages
+    messages = chat_message_history.get_messages()
+    
+    # Verify messages
+    assert len(messages) == 3
+    assert messages[0].role == MessageRole.HUMAN
+    assert messages[0].content == "Hello, how are you?"
+    assert messages[1].role == MessageRole.AI
+    assert messages[1].content == "I'm doing well, thank you!"
+    assert messages[2].role == MessageRole.SYSTEM
+    assert messages[2].content == "System message"
+
+
+def test_get_messages_as_dict(chat_message_history):
+    """Test getting messages as dictionaries."""
+    # Add messages
+    chat_message_history.add_human_message("Hello")
+    chat_message_history.add_ai_message("Hi there")
+    
+    # Get messages as dict
+    messages_dict = chat_message_history.get_messages_as_dict()
+    
+    # Verify messages
+    assert len(messages_dict) == 2
+    assert messages_dict[0]["role"] == "human"
+    assert messages_dict[0]["content"] == "Hello"
+    assert messages_dict[1]["role"] == "ai"
+    assert messages_dict[1]["content"] == "Hi there"
+    assert "timestamp" in messages_dict[0]
+    assert "metadata" in messages_dict[0]
+
+
+def test_clear_messages(chat_message_history):
+    """Test clearing messages."""
+    # Add messages
+    chat_message_history.add_human_message("Hello")
+    chat_message_history.add_ai_message("Hi there")
+    
+    # Verify messages were added
+    assert len(chat_message_history.get_messages()) == 2
+    
+    # Clear messages
+    chat_message_history.clear()
+    
+    # Verify messages were cleared
+    assert len(chat_message_history.get_messages()) == 0
+
+
+def test_search_messages(chat_message_history, monkeypatch):
+    """Test searching for messages."""
+    # Add messages with specific content
+    chat_message_history.add_human_message(
+        "I need information about machine learning algorithms"
+    )
+    chat_message_history.add_ai_message(
+        "Machine learning algorithms include decision trees, neural networks, and SVMs"
+    )
+    chat_message_history.add_human_message(
+        "Tell me more about neural networks"
+    )
+    
+    # Mock storage search results
+    mock_search_results = [
+        {
+            "context": "Machine learning algorithms include decision trees, neural networks, and SVMs",
+            "metadata": {
+                "role": "ai",
+                "timestamp": "2023-01-01T00:00:00"
+            }
+        }
+    ]
+    
+    # Monkeypatch the storage.search method
+    def mock_storage_search(*args, **kwargs):
+        return mock_search_results
+    
+    monkeypatch.setattr(chat_message_history.storage, "search", mock_storage_search)
+    
+    # Search for messages about neural networks
+    results = chat_message_history.search("neural networks")
+    
+    # Verify search results
+    assert len(results) > 0
+    assert any("neural networks" in result["content"] for result in results)
+
+
+def test_message_with_metadata(chat_message_history):
+    """Test adding and retrieving messages with metadata."""
+    # Add message with metadata
+    metadata = {"user_id": "123", "session_id": "abc"}
+    chat_message_history.add_human_message(
+        "Hello with metadata", metadata=metadata
+    )
+    
+    # Get messages
+    messages = chat_message_history.get_messages()
+    
+    # Verify metadata
+    assert len(messages) == 1
+    assert messages[0].metadata["user_id"] == "123"
+    assert messages[0].metadata["session_id"] == "abc"
+
+
+def test_chat_message_to_from_dict():
+    """Test converting ChatMessage to and from dictionary."""
+    # Create a message
+    timestamp = datetime.now()
+    message = ChatMessage(
+        role=MessageRole.HUMAN,
+        content="Test message",
+        timestamp=timestamp,
+        metadata={"key": "value"}
+    )
+    
+    # Convert to dict
+    message_dict = message.to_dict()
+    
+    # Verify dict
+    assert message_dict["role"] == "human"
+    assert message_dict["content"] == "Test message"
+    assert message_dict["timestamp"] == timestamp.isoformat()
+    assert message_dict["metadata"] == {"key": "value"}
+    
+    # Convert back to ChatMessage
+    new_message = ChatMessage.from_dict(message_dict)
+    
+    # Verify new message
+    assert new_message.role == MessageRole.HUMAN
+    assert new_message.content == "Test message"
+    assert new_message.timestamp.isoformat() == timestamp.isoformat()
+    assert new_message.metadata == {"key": "value"}