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AttributeError: module 'anyio._backends._asyncio' has no attribute 'run'

I am trying to test below code for Fastapi
from fastapi.testclient import TestClient
import unittest
client=TestClient(app)
class TestTelemetryAdapter(unittest.TestCase):
def test_ready(self):
a=client.get('/readiness')
self.assertEqual(a.status_code, status.HTTP_200_OK)
but I am getting error: AttributeError: module 'anyio._backends._asyncio' has no attribute 'run' for line: a=client.get
my python ver: 3.9.10
don't want to use async with func def

It is resolved after deleting the .pyc files of "asyncio" and "anyio".

How to patch a module that hasn't been imported by parent package's __init__.py

I'm trying to test a tool I'm building which uses some jMetalPy functionality. I had/have a previous version working but I am now trying to refactor out some external dependencies (such as the aforementioned jMetalPy).
Project Code & Structure
Here is a minimalist structure of my project.
MyToolDirectory
¦--/MyTool
¦----/__init__.py
¦----/_jmetal
¦------/__init__.py
¦------/core
¦--------/quality_indicator.py
¦----/core
¦------/__init__.py
¦------/run_manager.py
¦----/tests
¦------/__init__.py
¦------/test_run_manager.py
The _jmetal directory is to remove external dependency on the jMetalPy package - and I have copied only the necessary packages/modules that I need.
Minimal contents of run_manager.py
# MyTool\core\run_manager.py
import jmetal
# from jmetal.core.quality_indicators import HyperVolume # old working version
class RunManager:
def __init__(self):
pass
#staticmethod
def calculate_hypervolume(front, ref_point):
if front is None or len(front) < 1:
return 0.
hv = jmetal.core.quality_indicator.HyperVolume(ref_point)
# hv = HyperVolume(ref_point)
hypervolume = hv.compute(front)
return hypervolume
Minimal contents of test_run_manager.py
# MyTool\tests\test_run_manager.py
import unittest
from unittest.mock import MagicMock, Mock, patch
from MyTool import core
class RunManagerTest(unittest.TestCase):
def setUp(self):
self.rm = core.RunManager()
def test_calculate_hypervolume(self):
ref_points = [0.0, 57.5]
front = [None, None]
# with patch('MyTool.core.run_manager.HyperVolume') as mock_HV: # old working version
with patch('MyTool.core.run_manager.jmetal.core.quality_indicator.HyperVolume') as mock_HV:
mock_HV.return_value = MagicMock()
res = self.rm.calculate_hypervolume(front, ref_points)
mock_HV.assert_called_with(ref_points)
mock_HV().compute.assert_called_with(front)
Main Question
When I run a test with the code as-is, I get this error message:
E ModuleNotFoundError: No module named 'MyTool.core.run_manager.jmetal'; 'MyTool.core.run_manager' is not a package
But when I change it to:
with patch('MyTool.core.run_manager.jmetal.core') as mock_core:
mock_HV = mock_core.quality_indicator.HyperVolume
mock_HV.return_value = MagicMock()
res = self.rm.calculate_hypervolume(front, ref_points)
mock_HV.assert_called_with(ref_points)
mock_HV().compute.assert_called_with(front)
... now the test passes. What gives?!
Why can't (or rather, how can) I surgically patch the exact class I want (i.e., HyperVolume) without patching out an entire sub-package as well? Is there a way around this? There may be code in jmetal.core that needs to run normally.
Is the reason this isn't working only because there is no from . import quality_indicator statement in jMetalPy's jmetal\core\__init__.py ?
Because even with patch('MyTool.core.run_manager.jmetal.core.quality_indicator) throws:
E AttributeError: <module 'jmetal.core' from 'path\\to\\venv\\lib\\site-packages\\jmetal\\core\\__init__.py'> does not have the attribute 'quality_indicator'
Or is there something I'm doing wrong?
In the case that it is just about adding those import statements, I could do that in my _jmetal sub-package, but I was hoping to let the user default to their own jMetalPy installation if they already had one by adding this to MyTool\__init__.py:
try:
import jmetal
except ModuleNotFoundError:
from . import _jmetal as jmetal
and then replacing all instances of import jmetal with from MyTool import jmetal. However, I'd run into the same problem all over again.
I feel that there is some core concept I am not grasping. Thanks for the help.

AttributeError: module 'unittest' has no attribute 'Testcase'

I am new with python, i am trying to fllow the tutorial on youtube https://www.youtube.com/watch?v=6tNS--WetLI&t=168s
I have the error message
code:
import unittest
import calc
class TestCalc(unittest.Testcase):
def test_add(self):
result=calc.add(10,5)
self.assertEqual(result,15)
suite = unittest.TestLoader().loadTestsFromTestCase(TestCalc)
unittest.TextTestRunner(verbosity=2).run(suite)
I already seen all the answer on stackoverflow but the error resist.
Please help

You did a typo when writing the class name. It is with capitalized case TestCase, like you can see in the documentation.

Pytest mocker patch - how to troubleshoot?

I am having what I believe to be a common issue in using mock patching in that I can not figure out the right thing to patch.
I have two questions that I am hoping for help with.
Thoughts on how to fix the specific issue in the below example
And possibly most-importantly pro-tips/pointers/thoughts/suggestions on how to best troubleshoot the "which thing do I patch" question. The problem I'm having is, without a full understanding of how patching works, I really dont even know what I should be looking for and find myself playing a guessing game.
An example using pyarrow that is currently causing me pain:
mymodule.py
import pyarrow
class HdfsSearch:
def __init__(self):
self.fs = self._connect()
def _connect(self) -> object:
return pyarrow.hdfs.connect(driver="libhdfs")
def search(self, path: str):
return self.fs.ls(path=path)
test_module.py
import pyarrow
import pytest
from mymodule import HdfsSearch
#pytest.fixture()
def hdfs_connection_fixture(mocker):
mocker.patch("pyarrow.hdfs.connect")
yield HdfsSearch()
def test_hdfs_connection(hdfs_connection_fixture):
pyarrow.hdfs.connect.assert_called_once() # <-- succeeds
def test_hdfs_search(hdfs_connection_fixture):
hdfs_connection_fixture.search(".")
pyarrow.hdfs.HadoopFileSystem.ls.assert_called_once() # <-- fails
pytest output:
$ python -m pytest --verbose test_module.py
=========================================================================================================== test session starts ============================================================================================================
platform linux -- Python 3.7.4, pytest-5.0.1, py-1.8.0, pluggy-0.12.0 -- /home/bbaur/miniconda3/envs/dev/bin/python
cachedir: .pytest_cache
rootdir: /home/user1/work/app
plugins: cov-2.7.1, mock-1.10.4
collected 2 items
test_module.py::test_hdfs_connection PASSED [ 50%]
test_module.py::test_hdfs_search FAILED [100%]
================================================================================================================= FAILURES =================================================================================================================
_____________________________________________________________________________________________________________ test_hdfs_search _____________________________________________________________________________________________________________
hdfs_connection_fixture = <mymodule.HdfsSearch object at 0x7fdb4ec2a610>
def test_hdfs_search(hdfs_connection_fixture):
hdfs_connection_fixture.search(".")
> pyarrow.hdfs.HadoopFileSystem.ls.assert_called_once()
E AttributeError: 'function' object has no attribute 'assert_called_once'
test_module.py:16: AttributeError

You're not calling the assert on the Mock object, this is the correct assert:
hdfs_connection_fixture.fs.ls.assert_called_once()
Explanation:
When you access any attribute in a Mock object it will return another Mock object.
Since you patched "pyarrow.hdfs.connect" you've replaced it with a Mock, let's call it Mock A. Your _connect method will return that Mock A and you'll assign it to self.fs.
Now let's break down what's happening in the search method when you call self.fs.ls.
self.fs returns your Mock A object, then the .ls will return a different Mock object, let's call it Mock B. In this Mock B object you're doing the call passing (path=path).
In your assert you're trying to access pyarrow.hdfs.HadoopFileSystem, but it was never patched. You'll need do the assert on the Mock B object, which is at hdfs_connection_fixture.fs.ls
What to Patch
If you change your import in mymodule.py to this from pyarrow.hdfs import connect your patch will stop working.
Why is that?
When you patch something you're changing what a name points to, not the actual object.
Your current patch is patching the name pyarrow.hdfs.connect and in mymodule you're using the same name pyarrow.hdfs.connect so everything is fine.
However, if you use from pyarrow.hdfs import connect mymodule will have imported the real pyarrow.hdfs.connect and created a reference for it with the name mymodule.connect.
So when you call connect inside mymodule you're accessing the name mymodule.connect, which is not patched.
That is why you would need to patch mymodule.connect when using from import.
I'd recommend using from x import y when doing this kind of patching. It makes it more explicit what you're trying to mock and the patch will be limited to that module only, which can prevent unforeseen side-effects.
Source, this section in the Python documentation: Where to patch

To understand how patching works in python let's first understand the import statement.
When we use import pyarrow in a module (mymodule.py in this case) it does two operations :
It searches for the pyarrow module in sys.modules
It binds the results of that search to a name(pyarrow) in the local scope.
By doing something like: pyarrow = sys.modules['pyarrow']
NOTE: import statements in python doesn't execute code. The import statement brings a name into local scope. The execution of code happens as a side-effect only when python can't find a module in sys.modules
So, to patch pyarrow imported in mymodule.py we need to patch the pyarrow name present in the local scope of mymodule.py
patch('mymodule.pyarrow', autospec=True)
test_module.py
import pytest
from mock import Mock, sentinel
from pyarrow import hdfs
from mymodule import HdfsSearch
class TestHdfsSearch(object):
#pytest.fixture(autouse=True, scope='function')
def setup(self, mocker):
self.hdfs_mock = Mock(name='HadoopFileSystem', spec=hdfs.HadoopFileSystem)
self.connect_mock = mocker.patch("mymodule.pyarrow.hdfs.connect", return_value=self.hdfs_mock)
def test_initialize_HdfsSearch_should_connect_pyarrow_hdfs_file_system(self):
HdfsSearch()
self.connect_mock.assert_called_once_with(driver="libhdfs")
def test_initialize_HdfsSearch_should_set_pyarrow_hdfs_as_file_system(self):
hdfs_search = HdfsSearch()
assert self.hdfs_mock == hdfs_search.fs
def test_search_should_retrieve_directory_contents(self):
hdfs_search = HdfsSearch()
self.hdfs_mock.ls.return_value = sentinel.contents
result = hdfs_search.search(".")
self.hdfs_mock.ls.assert_called_once_with(path=".")
assert sentinel.contents == result
Use context managers to patch built-ins
def test_patch_built_ins():
with patch('os.curdir') as curdir_mock: # curdir_mock lives only inside with block. Doesn't lives outside
assert curdir_mock == os.curdir
assert os.curdir == '.'

Unit Testing AWS python lambda global variable patch doesnt work

I am trying to unit test Python based aws lambda code. I tried to use patch to mock environment variables but it throws error.How to handle global variables during unit testing. Any help is appreciated
Tried #mock #patch but nothing seems to be working. When executing the testcase the values seems to be empty
[registration.py]
import os
#Global Variables
DEBUG = os.environ.get("EnableLog")
rest_endpoint = os.environ.get('restApiEndpoint')
db_fn_endpoint = rest_endpoint+":3000/rpc/"
def lambda_handler(event,context):
return "success" #to see if this works
if __name__ == "__main__":
lambda_handler('', '')
Unit Test [test_registration.py]
import json
import pytest
import sys, os
from mock import patch
from businesslogic import registration
#mock.patch.dict(os.environ,{'EnableLog':'True'})
#mock.patch.dict(os.environ,{'restApiEndpoint':'http://localhost'})
#patch('registration.restApiEndpoint', 'http://localhost')
def test_lambda_handler():
assert lambda_handler() =="success"
When I run pytest test_registration.py
I get below exception
businesslogic\registration.py:6: in <module>
db_fn_endpoint = rest_endpoint+":3000/rpc/"
E TypeError: unsupported operand type(s) for +: 'NoneType' and 'str'

You can pass it as restApiEndpoint=http://localhost python -m pytest
OR
you if you are using sh file to run export before running test
export restApiEndpoint=http://localhost