Testing

MicroCoreOS is designed for testability. Since dependencies are injected via constructors, you can test business logic without booting the entire system.

Unit Testing Plugins

We recommend using pytest and anyio for testing plugins. Since plugins are just classes, you can instantiate them with mocks of the tools they need.

import pytest
from unittest.mock import AsyncMock, MagicMock
from domains.users.plugins.create_user_plugin import CreateUserPlugin

@pytest.mark.anyio
async def test_create_user_success():
    # 1. Arrange: Mock the tools
    mock_db = AsyncMock()
    mock_db.execute.return_value = 1  # Simulated ID
    
    mock_logger = MagicMock()
    
    # 2. Act: Instantiate the plugin manually
    plugin = CreateUserPlugin(
        db=mock_db,
        http=MagicMock(),
        event_bus=AsyncMock(),
        logger=mock_logger
    )
    
    result = await plugin.execute({"name": "John Doe", "email": "john@example.com"})
    
    # 3. Assert
    assert result["success"] is True
    assert result["data"]["id"] == 1
    mock_db.execute.assert_called_once()

Integration Testing

To test how multiple plugins and tools interact, you can use the Kernel in your tests to boot a mini-system.

from core.kernel import Kernel

async def test_system_integration():
    kernel = Kernel()
    await kernel.boot()
    
    # Access the container to get specific tools or plugins
    db = kernel.container.get('db')
    
    # ... perform actions and verify state ...
    
    await kernel.shutdown()

Best Practices

• Mock the Database: Use AsyncMock to simulate database responses. This keeps tests fast and deterministic.
• Trace Identity: When testing event-driven flows, verify that the ContextVars (e.g., identity, causality) are preserved.
• 1 Feature = 1 Test File: Just like the architecture, keep your tests focused on the feature they are validating.