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ImportError: No module named 'code.helper'

This is probably a question that has been asked multiple times, but I couldn't find a post with the answer I am looking for.
This is my structure:
/myproject
--/code
--/__init__.py
--/helper.py
--/tests
--/test_helper.py
--/docs
code/helper.py
def testFunction(x)
return x + 1
test/test_helper.py
import unittest
from code.helper import testFunction
class MyTest(unittest.TestCase):
def test(self):
self.assertEqual(testFunction(3), 4)
Whenever I run 'python3 -m unittest test_helper.py' from ~/home/user/Projects/myproject/tests - I get the error:
ImportError: No module named 'code.helper'; 'code' is not a package
I am not receiving any syntax errors.

You don't have myproject in your Python path. It works when the current directory is myproject, because the current directory is always on the Python path. When you change to tests, though, Python no longer knows where to find code.
192% pwd
/Users/chepner/myproject
192% python3 -m unittest tests/test_helper.py
.
----------------------------------------------------------------------
Ran 1 test in 0.000s
OK
192% cd tests
192% pwd
/Users/chepner/myproject/tests
192% python3 -m unittest test_helper.py
E
======================================================================
ERROR: test_helper (unittest.loader._FailedTest)
----------------------------------------------------------------------
ImportError: Failed to import test module: test_helper
Traceback (most recent call last):
File "/usr/local/Cellar/python/3.6.4_4/Frameworks/Python.framework/Versions/3.6/lib/python3.6/unittest/loader.py", line 153, in loadTestsFromName
module = __import__(module_name)
File "/Users/chepner/myproject/tests/test_helper.py", line 2, in <module>
from code.helper import testFunction
ModuleNotFoundError: No module named 'code.helper'; 'code' is not a package
----------------------------------------------------------------------
Ran 1 test in 0.000s
FAILED (errors=1)
The simple fix is, don't run the tests from the tests directory! Another solution, though, is to add myproject to the path before running the tests:
% PYTHONPATH=.. python3 -m unittest test_helper.py
.
----------------------------------------------------------------------
Ran 1 test in 0.000s
OK
You can add anything to PYTHONPATH that will correctly resolve to myproject; I just used the trivial relative path .. here, but an absolute path like PYTHONPATH=/Users/chepner/myproject would work, too.

How to debug unittests with pudb debugger?

I am having some trouble trying to debug some unit tests through the pudb debugger.
The tests run fine with python, but I had no luck runnign them with pudb.
I isolated the problem, getting to the following sample code:
class Math:
def pow(self, x, y):
return x ** y
import unittest
class MathTest(unittest.TestCase):
def testPow23(self):
self.assertEquals(8, Math().pow(2, 3))
def testPow24(self):
self.assertEquals(16, Math().pow(2, 4))
if __name__ == '__main__':
unittest.main()
The tests run fine:
$ python amodule.py
.
----------------------------------------------------------------------
Ran 2 tests in 0.001s
OK
But if running through pudb, it gives me the output:
----------------------------------------------------------------------
Ran 0 tests in 0.000s
OK
I've tried running using pudb amodule.py and also with python -m pudb.run amodule.py, but it makes no difference -- no tests are run in one or another way.
Should I be doing something different to debug unit tests using pudb?

Try placing a breakpoint on a useful line in your code:
from pudb import set_trace; set_trace()
The ways you tried to launch it might interfere with test discovery and/or not run your script with a __name__ of '__main__'.

Since this is a popular question, I feel I should also mention that most test running tools will require you to pass in a switch to prevent it from capturing the standard output and input (usually it's -s).
So, remember to run pytest -s when using Pytest, or nosetests -s for Nose, python manage.py test -s for Django tests, or check the documentation for your test running tool.

You can set a breakpoint even easier by:
import pudb; pu.db

Get staus if python tests all passed

I'm trying to write a Ruby script to execute all Python tests in a directory.
Here is the main part of the script:
system("python #{solution}/tests.py")
Is there a way to somehow understand if the tests have passed and to show output only for the ones that failed (or whatever else)? I just want to be able to tell for each test if it passed or not. (If not possible with Ruby, I'm open for solutions with Python, too)
The tests all look like this one:
import unittest
from solution import my_function
class MyFunctionTest(unittest.TestCase):
def test_my_function(self):
self.assertEqual(42, my_function(42))
if __name__ == '__main__':
unittest.main()
Thanks very much in advance! :)

You can print the output for failing tests with nosetests, which runs them all and condenses the passing tests:
$ nosetests
.............
----------------------------------------------------------------------
Ran 13 tests in 0.015s
OK
Adding a failing test:
$ nosetests
F.............
======================================================================
FAIL: test_failed (x32.tests.failing_test.FailingTest)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/Users/leigh/Projects/x32/x32/tests/failing_test.py", line 5, in test_failed
self.assertEqual(1, 2)
AssertionError: 1 != 2
----------------------------------------------------------------------
Ran 14 tests in 0.013s
FAILED (failures=1)
There's a guide for nose here, as well: https://nose.readthedocs.org/en/latest/
Alternatively you can go to the parent directory and run something like python -m pytest . to execute the tests, however this will tell you which ones pass as well.

Exceptions within unittests are not caught by the Python debugger

Consider a unittest suite like this:
import unittest
class TestClass(unittest.TestCase):
def test_set_trace(self):
raise Exception
if __name__ == '__main__':
suite = unittest.TestLoader().loadTestsFromTestCase(TestClass)
unittest.TextTestRunner(verbosity=2).run(suite)
When I put the following in the script and run it like so: python -m pdb tmp.py I would expect the Python debugger to catch the exception and bring me inside the test_set_trace method, however unittest catches the exception and hides it from pdb like so:
$ python -m pdb tmp.py
> tmp.py(1)<module>()
-> import unittest
(Pdb) c
test_set_trace (__main__.TestClass) ... ERROR
======================================================================
ERROR: test_set_trace (__main__.TestClass)
----------------------------------------------------------------------
Traceback (most recent call last):
File "tmp.py", line 5, in test_set_trace
raise Exception
Exception
----------------------------------------------------------------------
Ran 1 test in 0.000s
FAILED (errors=1)
The program finished and will be restarted
> tmp.py(1)<module>()
-> import unittest
(Pdb)
This is annoying when writing my tests as I need to go into the testing code and specify pdb.set_trace() manually, then step to the frame that contains the actual bug. Does anyone know of a workaround? Putting an explicit import pdb inside the testing code doesn't help, even if I put the import statement within the actual offending method.

Use TestSuite.debug.
debug()
Run the tests associated with this suite without collecting
the result. This allows exceptions raised by the test to be propagated
to the caller and can be used to support running tests under a
debugger.
Replace following line:
unittest.TextTestRunner(verbosity=2).run(suite)
with:
suite.debug()

Python: Conditional variables based on whether nosetest is running

I'm running nosetests which have a setup function that needs to load a different database than the production database. The ORM I'm using is peewee which requires that the database for a model is set in the definition.
So I need to set a conditional variable but I don't know what condition to use in order to check if nosetest is running the file.
I read on Stack Overflow that you can check for nose in sys.modules but I was wondering if there is a more exact way to check if nose is running.

Perhaps examining sys.argv[0] to see what command is running?

Examining sys.argv might work, but you can execute nose either with nosetests or python -m nose, which obviously will give you a different result.
I think the more robust way is to inspect the stack and see if the code is being called through a package called nose.
Example code:
import inspect
import unittest
def is_called_by_nose():
stack = inspect.stack()
return any(x[0].f_globals['__name__'].startswith('nose.') for x in stack)
class TestFoo(unittest.TestCase):
def test_foo(self):
self.assertTrue(is_called_by_nose())
Example usage:
$ python -m nose test_caller
.
----------------------------------------------------------------------
Ran 1 test in 0.009s
OK
$ nosetests test_caller
.
----------------------------------------------------------------------
Ran 1 test in 0.009s
OK
$ python -m unittest test_caller
F
======================================================================
FAIL: test_foo (test_caller.TestFoo)
----------------------------------------------------------------------
Traceback (most recent call last):
File "test_caller.py", line 14, in test_foo
self.assertTrue(is_called_by_nose())
AssertionError: False is not true
----------------------------------------------------------------------
Ran 1 test in 0.004s
FAILED (failures=1)