使用patch-Python添加溢出错误的副作用
我想模拟一个使用patch-Python添加溢出错误的副作用,python,unit-testing,exception,mocking,patch,Python,Unit Testing,Exception,Mocking,Patch,我想模拟一个溢出错误,因为我想在引发异常之后测试变量的值。但是,我不知道如何用我正在使用的库复制溢出错误。我在这个特定测试中使用的库是pysolar.solar特别是获取高度,获取方位和辐射方法 在无意识地尝试不同的数字来模拟溢出错误之后,我决定尝试模拟函数并引入一个副作用 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_azimut
溢出错误
,因为我想在引发异常之后测试变量的值。但是,我不知道如何用我正在使用的库复制溢出错误。我在这个特定测试中使用的库是pysolar.solar
特别是获取高度
,获取方位
和辐射方法
在无意识地尝试不同的数字来模拟溢出错误之后,我决定尝试模拟函数并引入一个副作用
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'])
**我开始用patch做什么**
"""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()
我希望它给我和溢出错误。。。但是,我的断言还是失败了,出现了一个溢出错误我猜我打错了补丁?我真的不明白为什么不管错误仍然是溢出错误
这是打印出来的内容
_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
现在我的错误是“modulenofounderror:没有名为'bigfolder.sun.sunposition.sun_position'的模块;'bigfolder.sun.sunposition'不是包
”
然后我只是将路径更改为“太阳位置。辐射模块。直接获取辐射”,但没有找到模块
因此,我的问题是:如何复制溢出错误,以便在引发异常时检查我设置的变量的值。为什么我介绍的第一个溢出错误仍然没有通过我的断言
谢谢
更新测试通过情况
按照@Gang的建议,复制了溢出错误。我意识到为了测试块的异常,特别是辐射
是np.nan
我必须修补我想要的溢出错误
的方法,而不是太阳位置的整个方法。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。因此,我将bigfolder.sun.sunposition.sun\u position.radiation\u module.get\u radiation\u direct
更改为pysolar.solar.radiation.get\u radiation\u direct
,这是具有我想要模拟的get\u radiation\u 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])
为什么我介绍的第一个溢出错误仍然没有通过我的断言
差不多了。assertRaises的正确方法是
:
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)
查看文档后,将讨论如何在assertRaises
assertRaises(异常、可调用、*args、**kwds)
乐趣(*args,**kwds)提升exc
这种用法是错误的:
self.assertRaises(OverflowError, sunposition.sun_position(lat=error_lat, lon=error_lon, time=error_time))
它应该是带有kwargs的func名称:
self.assertRaises(OverflowError, sunposition.sun_position, lat=error_lat, lon=error_lon, time=error_time)
伟大的我的观点是错误的。关于我打补丁的地方,我意识到这是一个模拟的溢出错误
而不是我想要的地方,因为最后我真正想要的是检查辐射
是否是np.nan
。但首先我必须确保溢出错误已经产生。谢谢你回答我的问题。我正在为我想要测试的内容(以防对任何人都有帮助)更新上述内容(使用正确的补丁)。
self.assertRaises(OverflowError, sunposition.sun_position, lat=error_lat, lon=error_lon, time=error_time)