# pytest-mock을 사용한 고급 Mock 예제
import pytest
from unittest.mock import patch, MagicMock, AsyncMock
from datetime import datetime

class TestAdvancedMocking:
    """고급 Mock 패턴 예제"""
    
    def test_with_datetime_mock(self):
        """datetime을 mock하는 예제"""
        with patch('datetime.datetime') as mock_datetime:
            mock_datetime.now.return_value = datetime(2024, 1, 1, 12, 0, 0)
            mock_datetime.side_effect = lambda *args, **kw: datetime(*args, **kw)
            
            # 테스트 코드
            from datetime import datetime
            assert datetime.now().year == 2024
    
    def test_with_context_manager_mock(self):
        """Context manager를 mock하는 예제"""
        mock_file = MagicMock()
        mock_file.__enter__.return_value.read.return_value = "file content"
        
        with patch('builtins.open', return_value=mock_file):
            with open('test.txt', 'r') as f:
                content = f.read()
            assert content == "file content"
    
    @pytest.mark.asyncio
    async def test_async_function_mock(self):
        """비동기 함수를 mock하는 예제"""
        mock_service = AsyncMock()
        mock_service.get_data.return_value = {"status": "success"}
        
        result = await mock_service.get_data()
        assert result["status"] == "success"
    
    def test_side_effect_with_exception(self):
        """side_effect로 예외를 발생시키는 예제"""
        mock_func = MagicMock()
        mock_func.side_effect = ValueError("테스트 에러")
        
        with pytest.raises(ValueError, match="테스트 에러"):
            mock_func()
    
    def test_multiple_return_values(self):
        """여러 번 호출 시 다른 값을 반환하는 예제"""
        mock_func = MagicMock()
        mock_func.side_effect = [1, 2, 3]
        
        assert mock_func() == 1
        assert mock_func() == 2
        assert mock_func() == 3
    
    def test_property_mock(self):
        """Property를 mock하는 예제"""
        mock_obj = MagicMock()
        type(mock_obj).name = PropertyMock(return_value="Test Name")
        
        assert mock_obj.name == "Test Name"