我想模仿OverflowError因为我想测试变量的值是在引发异常之后。但是，我不知道如何使用我正在使用的库复制OverflowError。我在此特定测试中使用的库pysolar.solar具体为get_altitude，get_azimuth和radiation methods
在盲目地尝试不同的数字以尝试模拟OverflowError之后，我决定尝试模拟该函数并引入副作用。
我正在测试的代码 sunposition.py
import numpy as np
import pandas as pd
from pysolar.solar import get_altitude, get_azimuth, radiation as radiation_module
def sun_position(lat: float, lon: float, time: pd.Timestamp = None) -> List[float]:
if time is None:
time = pd.Timestamp.now(tz='UTC')
dt = time.to_pydatetime()
altitude = get_altitude(lat, lon, dt)
azimuth = get_azimuth(lat, lon, dt)
try:
radiation = radiation_module.get_radiation_direct(dt, altitude)
except OverflowError:
radiation = np.nan
return pd.Series([altitude, azimuth, radiation], index=['Alt', 'Azi', 'Rad'])
**我开始使用补丁**
"""Test sunposition module"""
import unittest
import numpy as np
import pandas as pd
from unittest.mock import MagicMock, patch, Mock
from bigfolder.sun import sunposition
class TestSunposition(unittest.TestCase):
"""Test functions in sunposition."""
def test_sun_position_overflow_error(self):
error_lat = 23
error_lon = 12
error_time = pd.Timestamp('2007-02-18 15:13:05', tz="UTC")
mock_args = {'side_effect': OverflowError}
with patch('bigfolder.sun.sunposition.sun_position', **mock_args):
# run the test
self.assertRaises(OverflowError, sunposition.sun_position(lat=error_lat, lon=error_lon, time=error_time))
if __name__ == '__main__':
unittest.main()
我原本以为它会给我和OverFlow错误...而且确实如此，但是我的断言无论如何都出现了 OverflowError 我的猜测是我修错了地方？无论错误何时仍为OverFlow Error
这是打印出来的
_mock_self = <MagicMock name='sun_position' id='102333856'>, args = ()
kwargs = {'lat': 23, 'lon': 12, 'time': Timestamp('2007-02-18 15:13:05+0000', tz='UTC')}
self = <MagicMock name='sun_position' id='102333856'>, _new_name = ''
_new_parent = None
_call = call(lat=23, lon=12, time=Timestamp('2007-02-18 15:13:05+0000', tz='UTC'))
seen = set(), skip_next_dot = False, do_method_calls = False
name = 'sun_position'
def _mock_call(_mock_self, *args, **kwargs):
self = _mock_self
self.called = True
self.call_count += 1
_new_name = self._mock_new_name
_new_parent = self._mock_new_parent
_call = _Call((args, kwargs), two=True)
self.call_args = _call
self.call_args_list.append(_call)
self.mock_calls.append(_Call(('', args, kwargs)))
seen = set()
skip_next_dot = _new_name == '()'
do_method_calls = self._mock_parent is not None
name = self._mock_name
while _new_parent is not None:
this_mock_call = _Call((_new_name, args, kwargs))
if _new_parent._mock_new_name:
dot = '.'
if skip_next_dot:
dot = ''
skip_next_dot = False
if _new_parent._mock_new_name == '()':
skip_next_dot = True
_new_name = _new_parent._mock_new_name + dot + _new_name
if do_method_calls:
if _new_name == name:
this_method_call = this_mock_call
else:
this_method_call = _Call((name, args, kwargs))
_new_parent.method_calls.append(this_method_call)
do_method_calls = _new_parent._mock_parent is not None
if do_method_calls:
name = _new_parent._mock_name + '.' + name
_new_parent.mock_calls.append(this_mock_call)
_new_parent = _new_parent._mock_new_parent
# use ids here so as not to call __hash__ on the mocks
_new_parent_id = id(_new_parent)
if _new_parent_id in seen:
break
seen.add(_new_parent_id)
ret_val = DEFAULT
effect = self.side_effect
if effect is not None:
if _is_exception(effect):
> raise effect
E OverflowError
那么我认为我必须在错误的地方打补丁并且比我应该更早地介绍副作用？所以我改为在try块中修改方法。 这是我的以下代码。
def test_sun_position_overflow_error(self):
error_lat = 23
error_lon = 12
error_time = pd.Timestamp('2007-02-18 15:13:05', tz="UTC")
mock_args = {'side_effect': OverflowError}
with patch('bigfolder.sun.sunposition.sun_position.radiation_module.get_radiation_direct', **mock_args):
# run the test
self.assertRaises(OverflowError, sunposition.sun_position(lat=error_lat, lon=error_lon, time=error_time))
现在我的错误是＆＃34; ModuleNotFoundError: No module named 'bigfolder.sun.sunposition.sun_position'; 'bigfolder.sun.sunposition' is not a package＆＃34;
我刚刚将路径更改为'sun_position.radiation_module.get_radiation_direct'，但找不到任何模块。
所以我的问题是：如何复制一个OverflowError，这样我就可以检查一旦引发Exception就设置的变量的值。为什么我引入的第一个OverflowError仍未通过我的断言？
由于
更新测试通过
遵循@Gang的建议后，OverFlowError被复制了。我意识到为了测试异常的块，特别是radiation然后np.nan我必须修补我想要的方法以获得OverFlowError而不是sun_position的整个方法。当我尝试这样做时，我错误地导入了它，因为我认为外部库是代码的一部分。所以我将bigfolder.sun.sunposition.sun_position.radiation_module.get_radiation_direct更改为pysolar.solar.radiation.get_radiation_direct，这是具有我想要模拟的get_radiation_direct方法的外部库。
def test_sun_position_overflow_error(self):
lat = 23
lon = 12
time = pd.Timestamp('2007-02-18 15:13:05', tz="UTC")
# get_radiation_direct will now produce an OverFlowError(regardless of coordinates)
mock_args = {'side_effect': OverflowError}
# mock get_radiation_direct and produce OverFlowError
with patch('pysolar.solar.radiation.get_radiation_direct', **mock_args):
# Check radiation column is nan value
assert math.isnan(sunposition.sun_position(lat=lat, lon=lon, time=time)[2])
答案 0 :(得分：1)
为什么我介绍的第一个OverflowError仍未通过我的断言？
几乎就在那里。通往var count = 0;
document.getElementById("word-checker").onclick = function () {
// use count here
// ...
}
的正确方法：
assertRaises查看文档后，如何在def test_sun_position_overflow_error(self):
# This has to be here first and without func call
with self.assertRaises(OverflowError):
# patch the function to have an exception no matter what
mock_args = {'side_effect': OverflowError}
with patch('bigfolder.sun.sunposition.sun_position', **mock_args):
# call this func to trigger an exception
sunposition.sun_position(lat=error_lat, lon=error_lon, time=error_time)
assertRaises（例外，可调用，* args，** kwds）
有趣（* args，** kwds）引发了exc
这种用法是错误的：
assertRaises它应该是kwargs的函数名称：
self.assertRaises(OverflowError, sunposition.sun_position(lat=error_lat, lon=error_lon, time=error_time))