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How to use "argparse" argument across python files?

Let's say I have a main.py and a subfile.py.
main.py
import subfile #Writen by myself. I want to share argparse with it
import argparse
parser = argparse.ArgumentParser(description='test',formatter_class=argparse.ArgumentDefaultsHelpFormatter)
parser.add_argument('--a', type=int, default=0, help='test')
args = parser.parse_args()
args.a=0
subfile.fun()
args.a=1
subfile.fun()
args.a=0
subfile.fun()
2.subfile.py
xxxxxsome operation here to use args in main.pyxxxx
# In tensorflow wrapped argparse, I just need to define the same ArgumentParser to use args defined in main.py.
# But it's not suitable for "argparse", which would cause conflicts.
def fun():
if args.a==0:
print('yes')
else:
print('no')
In main.py I use argparse to pass arguments, and main.py use subfile.py.
Now, I want to use args define in main.py, how can I do?
(The codes are an simplified example described the problem, which can't be solved by reorganized code and has to be solved by using args in subfile.py. )
Thanks for your help! I have been torture by some bugs for the whole day and your answer would help me out. Appreciated!
edit:
Actually I know how to pass a paramter to a funciton. But as I said above, I writed the example code just for the key solution: is how to use the library "argparse" across python file, which is supported in a similar library in tensorflow "FLAG".

You can add another file, let's call it arguments.py for example.
Then include at the top of both main.py and subfile.py the following line:
from arguments import args
You then move all the code relating to parsing the command line arguments to arguments.py.
This way both the modules in main.py and subfile.py have access to the same args object.

def
When you define a function, if you need parameters, you can add them between the parentesis.
This is the model:
def fun(par: type) -> ReturnedType:
pass
For example:
def fun(a: int) -> None:
if a == 0:
print("Yes")
else:
print("No")
Then, when calling subfile.fun() add the argument like this:
subfile.fun(a = a)
or like this:
subfile.fun(a)
return
Remember your function doesn't return anything.
If you want to assign to a variable "yes" or "no" you can do like this:
def fun(a: int) -> str:
if a == 0:
return "Yes"
else:
return "No"
If you want to return only "yes" or "no", you might like to return a boolean instead:
def fun(a: int) -> bool:
if a == 0:
return True
else:
return False
You can also write the if statement in one line:
print('Yes') if (a == 0) else print('No)
import
To import subfile.py the file should be in the same directory.
Otherwise you have to do like this:
from sys import path
# Imagine you need C:\\Python\MyFolder\subfile.py
path.append(r"C:\\Python\MyFolder")
import subfile

Python mock launches whole program instead of substituting input to specific method

I have a program, like:
module "Main":
import SymbolCalculator as sc
# Defining constants:
TEXT_INTRO = sc.TEXT_INTRO
TEXT_INVITE = "Please print any sentence below:\n"
sentence = ""
# Printing introduction to the program:
print TEXT_INTRO
def getting_result():
# Getting input string from console
sentence = sc.get_input_from_prompt(TEXT_INVITE)
# Forming result list via methods defined in SymbolCalculator module
return sc.characters_calculator(sentence)
result_list = getting_result()
# Computing summary via method defined in SymbolCalculator module
sc.printing_summary(sentence, result_list)
# Printing tuples with characters and their occurrences raw-by-raw
sc.printing_list(result_list)
raw_input("Please press any button to quit the program.")
print 'Bye!!!'
And I'm trying to create a simple unit test with mocked raw_input (updated):
from unittest import TestCase, main
from mock import patch
from Ex_41_42_SymbolCalculatorMain import getting_result
class Ex_4a1_SymbolCalculatorUnitTestWMock(TestCase):
##patch ('Ex_41_42_SymbolCalculator.get_input_from_prompt', return_value = 'aabc')
def test_valid_input(self):
with patch('__builtin__.raw_input', return_value = 'aaabbc') as _raw_input:
self.assertEqual(getting_result(), [('a', 3), ('b', 2), ('c', 1)])
_raw_input.assert_called_once_with('Please print any sentence below:\n')
#patch ('Ex_41_42_SymbolCalculator.get_input_from_prompt', return_value = '')
def test_empty_input(self, mock):
self.assertEqual(getting_result(), [])
if __name__ == "__main__":
main()
As well I tried to go via decoration of the tested method by itself, like:
...
#patch ('Ex_41_42_SymbolCalculator.get_input_from_prompt', return_value = 'aabc')
...
My problem is that when I launch the test, all the "Main" module runs at the moment of getting_result method calling. So it starts from the very beginning, asks me to make an input via command prompt, etc. Thus not only test, but the whole regular program is running.
While I'm expecting that only getting_result method is called being provided with return_value.
Please advise.

When you import a module, all the code in the module is run. It doesn't matter that you used from Ex_41_42_SymbolCalculatorMain import getting_result instead of import Ex_41_42_SymbolCalculatorMain; you're still importing the module. There's no way to just "get" one function without executing the rest of the code in the module.
Instead, you should put that code in a function, and then call it from within an if __name__ == "__main__" block, like this:
def getting_result():
# Getting input string from console
sentence = sc.get_input_from_prompt(TEXT_INVITE)
# Forming result list via methods defined in SymbolCalculator module
return sc.characters_calculator(sentence)
def do_stuff():
print TEXT_INTRO
result_list = getting_result()
# Computing summary via method defined in SymbolCalculator module
sc.printing_summary(sentence, result_list)
# Printing tuples with characters and their occurrences raw-by-raw
sc.printing_list(result_list)
raw_input("Please press any button to quit the program.")
print 'Bye!!!'
if __name__ == "__main__":
do_stuff()
Then do_stuff() will only be run if you execute that file directly, not if you import it. This will allow you to import the module without running the stuff in do_stuff. You can learn more about the __main__ business by searching this site for zillions of questions about it (such as this one).

AttributeError: while using monkeypatch of pytest

src/mainDir/mainFile.py
contents of mainFile.py
import src.tempDir.tempFile as temp
data = 'someData'
def foo(self):
ans = temp.boo(data)
return ans
src/tempDir/tempFile.py
def boo(data):
ans = data
return ans
Now I want to test foo() from src/tests/test_mainFile.py and I want to mock temp.boo(data) method in foo() method
import src.mainDir.mainFile as mainFunc
testData = 'testData'
def test_foo(monkeypatch):
monkeypatch.setattr('src.tempDir.tempFile', 'boo', testData)
ans = mainFunc.foo()
assert ans == testData
but I get error
AttributeError: 'src.tempDir.tempFile' has no attribute 'boo'
I expect ans = testData.
I would like to know if I am correctly mocking my tempDir.boo() method or I should use pytest's mocker instead of monkeypatch.

You're telling monkeypatch to patch the attribute boo of the string object you pass in.
You'll either need to pass in a module like monkeypatch.setattr(tempFile, 'boo', testData), or pass the attribute as a string too (using the two-argument form), like monkeypatch.setattr('src.tempDir.tempFile.boo', testData).

My use case was was slightly different but should still apply. I wanted to patch the value of sys.frozen which is set when running an application bundled by something like Pyinstaller. Otherwise, the attribute does not exist. Looking through the pytest docs, the raising kwarg controls wether or not AttributeError is raised when the attribute does not already exist. (docs)
Usage Example
import sys
def test_frozen_func(monkeypatch):
monkeypatch.setattr(sys, 'frozen', True, raising=False)
# can use ('fq_import_path.sys.frozen', ...)
# if what you are trying to patch is imported in another file
assert sys.frozen

Update: mocking function calls can be done with monkeypatch.setattr('package.main.slow_fun', lambda: False) (see answer and comments in https://stackoverflow.com/a/44666743/3219667) and updated snippet below
I don't think this can be done with pytest's monkeypatch, but you can use the pytest-mock package. Docs: https://github.com/pytest-dev/pytest-mock
Quick example with the two files below:
# package/main.py
def slow_fun():
return True
def main_fun():
if slow_fun():
raise RuntimeError('Slow func returned True')
# tests/test_main.py
from package.main import main_fun
# Make sure to install pytest-mock so that the mocker argument is available
def test_main_fun(mocker):
mocker.patch('package.main.slow_fun', lambda: False)
main_fun()
# UPDATE: Alternative with monkeypatch
def test_main_fun_monkeypatch(monkeypatch):
monkeypatch.setattr('package.main.slow_fun', lambda: False)
main_fun()
Note: this also works if the functions are in different files

HTMLTestRunner error：raise TypeError("{} is not callable".format(repr(test)))

When I use HTMLTestRunner for Python 3.5，it shows an error.
I have changed the HTMLTestRunner for support python 3.5.
The code :
import pymysql
import pymysql
import unittest
import time
import unittest.suite
import HTMLTestRunner
import sys
def hell(a):
print(a)
return a
testunit = unittest.TestSuite()
testunit.addTest(hell('ad'))
filename = '/Users/vivi/Downloads/aa.html'
fp = open(filename, 'wb')
runner = HTMLTestRunner.HTMLTestRunner(stream=fp, title=u'print', description=u'简单')
runner.run(testunit)
When I run it, I got this error:
Traceback (most recent call last):
File "/Applications/Python 3.5/……/B.py", line 30, in <module>
testunit.addTest(hell('ad'))
File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/unittest/suite.py", line 47, in addTest
raise TypeError("{} is not callable".format(repr(test)))
TypeError: 'ad' is not callable
What should I do to make the script works?

You're adding the result of the call to hell('ad') to your tests, not the hell function itself. Since the hell function returns its argument, it returns the string ad, which is not a callable (function or the like).
Use
testunit.addTest(hell)
instead.
What about that argument then, how do you pass that?
Well, there are ways to do that, but generally, try not to let your unit test functions take an argument. Thus, hell() should siply not take an argument.
If you code your unit test correctly, you'll find that you rarely need to pass it an argument.

The line testunit.addTest(hell('ad')) doesn't do what you intend it to do. It doesn't tell the test suite to run hell('ad') later on. Rather, it calls that function immediately and passed the return value (which happens to be the string 'ad' you gave it as an argument) to addTest. That causes the exception later on, since a string is not a valid test case.
I'm not exactly sure how you should fix this. Your hell function doesn't appear to actually test anything, so there's not an obvious way to transform it into a proper test. There is a unittest.FunctionTestCase class that wraps a function up as a TestCase, but it doesn't appear to have any way of passing arguments to the function. Probably you should write a TestCase subclass class, and add various test_-prefixed methods that actually test things.

I had a right answer for my question, give the code:
# -*- coding: utf-8 -*-
import unittest
import HTMLTestRunner
def hell(a):
print(a)
return a
class HellTest(unittest.TestCase):
def setUp(self):
self.hell = hell
def tearDown(self):
pass
def testHell(self):
self.assertEqual(self.hell('aaa'), 'aaa')
if __name__ == '__main__':
testunit = unittest.TestSuite()
testunit.addTest(HellTest('testHell'))
filename = '/Users/vivi/Downloads/aa.html'
fp = open(filename, 'wb')
runner = HTMLTestRunner.HTMLTestRunner(stream=fp, title=u'不要生成error啦！', description=u'简单1112')
runner.run(testunit)
fp.close()
But, I do not know why add the class code 'class HellTest()'.The answer comes from a Chinese people whoes name is '幽谷奇峰'。Source code reference：https://segmentfault.com/q/1010000007427143?_ea=1345414

Mocking urllib2.urlopen().read() for different responses

I am trying to mock the urllib2.urlopen library in a way that I should get different responses for different urls I pass into the function.
The way I am doing it in my test file now is like this
#patch(othermodule.urllib2.urlopen)
def mytest(self, mock_of_urllib2_urllopen):
a = Mock()
a.read.side_effect = ["response1", "response2"]
mock_of_urllib2_urlopen.return_value = a
othermodule.function_to_be_tested() #this is the function which uses urllib2.urlopen.read
I expect the the othermodule.function_to_be_tested to get the value "response1" on first call and "response2" on second call which is what side_effect will do
but the othermodule.function_to_be_tested() receives
<MagicMock name='urlopen().read()' id='216621051472'>
and not the actual response. Please suggest where I am going wrong or an easier way to do this.

The argument to patch needs to be a description of the location of the object, not the object itself. So your problem looks like it may just be that you need to stringify your argument to patch.
Just for completeness, though, here's a fully working example. First, our module under test:
# mod_a.py
import urllib2
def myfunc():
opened_url = urllib2.urlopen()
return opened_url.read()
Now, set up our test:
# test.py
from mock import patch, Mock
import mod_a
#patch('mod_a.urllib2.urlopen')
def mytest(mock_urlopen):
a = Mock()
a.read.side_effect = ['resp1', 'resp2']
mock_urlopen.return_value = a
res = mod_a.myfunc()
print res
assert res == 'resp1'
res = mod_a.myfunc()
print res
assert res == 'resp2'
mytest()
Running the test from the shell:
$ python test.py
resp1
resp2
Edit: Whoops, initially included the original mistake. (Was testing to verify how it was broken.) Code should be fixed now.