def test_can_dispatch_validation(self, _has_right_type, validate):
"""
Validator must call methods to check the file type and format.
"""
# Patch `open` built-in on target module
m = mock_open()
import runner.document_validation
with patch.object(runner.document_validation, 'open', m, create=True):
# Create a mock file (for the context manager)
mock_file_pointer = m.return_value
validator = DocumentValidatorProvider(*self.initial_data)
validator.run()
# Assert that the required methods were called
_has_right_type.assert_called_once_with()
validate.assert_called_with(mock_file_pointer)