只是模拟两者os.path.isfile
and the open()
调用,并传入一个假文件名(毕竟,您不应该传入一个打开的文件)。
模拟库包含后者的实用程序:mock_open() https://docs.python.org/3/library/unittest.mock.html#mock-open:
@mock.patch('os.path.isfile')
def test_CheckConfig_with_file(mock_isfile):
mock_isfile.return_value = True
config_data = mock.mock_open(read_data='data')
with mock.patch('mymodule.open', config_data) as mock_open:
expected = parsed_file_data
actual = CheckConfig('mocked/filename').config
assert expected == actual
这导致if isinstance(data, list):
测试为假(因为data
是一个字符串),然后是elif os.path.isfile(data):
返回True
,以及open(data)
调用以使用您的模拟数据mock_open()
result.
您可以使用mock_open
变量来断言open()
被调用时使用了正确的数据(mock_open. assert_called_once_with('mocked/filename')
例如)。
Demo:
>>> import os.path
>>> from unittest import mock
>>> class CheckConfig(object):
... def __init__(self, config):
... self.config = self._check_input_data(config)
... def _check_input_data(self, data):
... if isinstance(data, list):
... return self._parse(data)
... elif os.path.isfile(data):
... with open(data) as f:
... return self._parse(f.readlines())
... def _parse(self, data):
... return data
...
>>> with mock.patch('os.path.isfile') as mock_isfile:
... mock_isfile.return_value = True
... config_data = mock.mock_open(read_data='line1\nline2\n')
... with mock.patch('__main__.open', config_data) as mock_open:
... actual = CheckConfig('mocked/filename').config
...
>>> actual
['line1\n', 'line2\n']
>>> mock_open.mock_calls
[call('mocked/filename'),
call().__enter__(),
call().readlines(),
call().__exit__(None, None, None)]