## Testing Exceptions

### Testing Expected Exceptions

```python
def test_divide_by_zero():
    """Test that dividing by zero raises ZeroDivisionError."""
    with pytest.raises(ZeroDivisionError):
        divide(10, 0)

def test_custom_exception():
    """Test custom exception with message."""
    with pytest.raises(ValueError, match="invalid input"):
        validate_input("invalid")
```

### Testing Exception Attributes

```python
def test_exception_with_details():
    """Test exception with custom attributes."""
    with pytest.raises(CustomError) as exc_info:
        raise CustomError("error", code=400)

    assert exc_info.value.code == 400
    assert "error" in str(exc_info.value)
```