When playing with nose and trying to combine it with cython I can't quite get it all to work the way I'd like. The code is organised like this:
.
├── setup.py
└── src
├── calc
│ ├── factorial.py
│ ├── __init__.py
│ └── tests.py
└── cycalc
├── tests.py
└── triangle.pyx
Each of the tests.py contains 2 tests, one succeeds, one fails. The result of running setup.py nosetests is that only calc/tests.py are run. If I after this run nosetests3 src/cycalc the two tests in cycalc/tests.py are run. However, if I clean up all build files it fails because cycalc/triangle.pyx hasn't been built into a shared lib.
Then I tried adding the file src/cycalc/__init__.py, now setup.py nosetests picks up cycalc/tests.py but it fails to find the required module, it was placed in src.
How do I arrange my cython source and tests to make setup.py nosetests find everything it needs?
For nose to run your tests automatically you should add them into a folder called tests containing all your tests. Like this:
.
|-setup.py
|-src
|---calc
|------factorial.py
|------__init__.py
|---cycalc
|------triangle.pyx
|------__init__.py
|-tests
|---__init__.py
|---test_calc.py
|---test_cycalc.py
This way both tests will be run automatically with everything in the same path. If you remove the built files you need to run python setup.py build before the tests will work again.
Related
I have the following folder structure in my project:
my-project
src/
__init__.py
script.py
test/
__init__.py
test_script.py
Ideally I want to have a separate folder where all the unit tests go. My test_script.py looks something like this:
from src.script import my_object
class TestClass(unittest.TestCase):
def test_script_object(self):
# unit test here
pass
if __name__ == 'main':
unittest.main()
When I try to run the script (using python test_script.py) I get the following error:
Traceback (most recent call last):
File "test_script.py", line 4, in <module>
from src.script import my_object
ModuleNotFoundError: No module named 'src'
I was following the instructions from this other thread, and I even tried appending src to the sys path (which forces me to change how I do imports in the rest of the project). When I'm not trying to append to the sys path, both of my __init__.py files are empty.
I am using python 3.8.
Does anyone have any suggestions? I'm new to unit testing in python, so maybe there is a better structure or other conventions I'm not aware of. Thanks in advance for your help!
Generally, any instructions that have you modifying sys.path in order to run your tests are sending you in the wrong direction. Your testing tool should be able to discover both your tests and your application code without requiring that sort of hackery.
I generally use pytest for running my tests. I would structure your example like this:
my-project/
├── src
│ ├── conftest.py
│ └── myproject
│ ├── __init__.py
│ └── script.py
└── tests
├── __init__.py
└── test_script.py
Assuming that src/myproject/script.py looks like this:
def double(x: int):
return x*2
And tests/test_script.py look like this:
import myproject.script
def test_double():
res = myproject.script.double(2)
assert res == 4
I can run tests from the my-project directory by simply running pytest:
$ pytest
========================================== test session starts ==========================================
platform linux -- Python 3.11.1, pytest-7.2.0, pluggy-1.0.0
rootdir: /home/lars/tmp/python/my-project
collected 1 item
tests/test_script.py . [100%]
=========================================== 1 passed in 0.00s ===========================================
In this setup, the file src/conftest.py is what allows pytest to automatically discover the location of your application code. Alternatively, you could instead specify that in your pyproject.toml file like this:
[tool.pytest.ini_options]
pythonpath = [
"src"
]
pytest also works if you write unittest-style tests as you show in your question; the above behavior would be identical if tests/test_script.py looked like:
import unittest
import myproject.script
class TestScript(unittest.TestCase):
def test_double(self):
res = myproject.script.double(2)
self.assertEqual(res, 4)
if __name__ == '__main__':
unittest.main()
(But I prefer pytest's simpler syntax.)
Possibly useful reading:
Good integration practices
If you really want to use unittest you can use the same directory layout, but you will need to update sys.path for it to run correctly. The easiest way to do that is:
PYTHONPATH=$PWD/src python -m unittest
This will automatically discover all your tests and run them. You can run a single test like this:
PYTHONPATH=$PWD/src python -m tests.test_script
You can avoid needing to modify sys.path if you use a simpler directory layout:
my-project/
├── myproject
│ ├── __init__.py
│ └── script.py
└── tests
├── __init__.py
└── test_script.py
Both pytest and python -m unittest, when run from the my-project directory, will correctly discover and run your tests without requiring any path modifications.
I have a question in how to properly create a path in Python (Python 3.x).
I developed a small scraping app in Python with the following directory structure.
root
├── Dockerfile
├── README.md
├── tox.ini
├── src
│ └── myapp
│ ├── __init__.py
│ ├── do_something.py
│ └── do_something_else.py
└── tests
├── __init__.py
├── test_do_something.py
└── test_do_something_else.py
When I want to run my code, I can go to the src directory and do with
python do_something.py
But, because do_something.py has an import statement from do_something_else.py, it fails like:
Traceback (most recent call last):
File "src/myapp/do_something.py", line 1, in <module>
from src.myapp.do_something_else import do_it
ModuleNotFoundError: No module named 'src'
So, I eventually decided to use the following command to specify the python path:
PYTHONPATH=../../ python do_something.py
to make sure that the path is seen.
But, what are the better ways to feed the path so that my app can run?
I want to know this because when I run pytest via tox, the directory that I would run the command tox would be at the root so that tox.ini is seen by tox package. If I do that, then I most likely run into a similar problem due to the Python path not properly set.
Questions I want to ask specifically are:
where should I run my main code when creating my own project like this? root as like python src/myapp/do_something.py? Or, go to the src/myapp directory and run like python do_something.py?
once, the directory where I should execute my program is determined, what is the correct way to import modules from other py file? Is it ok to use from src.myapp.do_something_else import do_it (this means I must add path from src directory)? Or, different way to import?
What are ways I can have my Python recognize the path? I am aware there are several ways to make the pass accessible as below:
a. write export PYTHONPATH=<path_of_my_choice>:$PYTHONPATH to make the
path accessible temporarily, or write that line in my .bashrc to make it permanent (but it's hard to reproduce when I want to automate creating Python environment via ansible or other automation tools)
b. write import sys; sys.path.append(<root>) to have the root as an accessible path
c. use pytest-pythonpath package (but this is not really a generic answer)
Thank you so much for your inputs!
my environment
OS: MacOS and Amazon Linux 2
Python Version: 3.7
Dependency in Python: pytest, tox
I would suggest to use setup.py to make this a python package. Then you can install it in development mode python setup.py develop. This way it will be available in your python environment w/o needing to specify the PYTHONPATH.
For testing, you can simply install the package python setup.py install.
Hope that helps.
Two simple steps should make it happen. Python experts can comment if this is a good way to do it (especially going by the concluding caution raised towards the end of this post).
I would have done it like below.
First I would have put a "__init__.py" in root so that hierarchy looks like below. This way python will treat the folder as a package.
root
├── Dockerfile
├── README.md
├── tox.ini
├── __init__.py
├── src
│ └── myapp
│ ├── __init__.py
│ ├── do_something.py
│ └── do_something_else.py
└── tests
├── __init__.py
├── test_do_something.py
└── test_do_something_else.py
Then in "do_something.py", I would have added these lines at the top. In the second line please put the full path to the "root" directory.
import sys
sys.path += ['/home/SomeUserName/SomeFolderPath/root']
from src.myapp.do_something_else import do_it
Please note that the second line will essentially modify the sys.path by adding the root folder path (I guess until the interpreter quits). If this is not what you can afford then I am sorry.
We using py.test. We try to put different conftest.py files in different folders to split our fixtures:
tests/api/
├── conftest.py
├── folder1
│ └── conftest.py
├── folder2
│ └── conftest.py
But when run the tests this error occurs:
____ ERROR collecting api/folder1/conftest.py ____
import file mismatch:
imported module 'conftest' has this __file__ attribute:
/tests/api/folder2/conftest.py
which is not the same as the test file we want to collect:
/tests/api/folder1/conftest.py
HINT: remove __pycache__ / .pyc files and/or use a unique basename for your test file modules
Why is that? How fix it?
PS. Removing __pycache__.pyc did not help.
PPS. __init__.py files already exist in each folder.
I had the same issue. To solve this you need to create python packages instead of directories. Then pytest will look at the conftest.py in your package instead of root directory. Hope, this will help you.
tests/api/
├── conftest.py
├── package1 # not folder
│ └── conftest.py
├── package2 # not folder
│ └── conftest.py
Your use case sounds like this example in the pytest documentation. Because of that I think it's possible to use conftest.pys at different levels to override fixtures.
The errors you're seeing may be related to incorrect imports. Is your test code importing from conftest files directly? Are your conftest files importing from your tests? Are any of your imports relative instead of absolute? If any of these are true, that may be your issue. I recommend only using absolute imports, and avoid imports between conftest.pys and test files.
Rename one (or both) of the test files Pytest is complaining about. Pytest is telling you in the error message to do this (i.e. change the basename, meaning don't name all your test files conftest.py). For example, you can fix it by doing:
tests/api/
├── conftest.py
├── folder1
│ └── test_conf1.py
├── folder2
│ └── test_conf2.py
In your case, the module names conflict (you have three conftest.pys). This is a quirk of Pytest AFAIK. Pytest could get around this by managing full package/module paths: but it doesn't do this (probably for good reason, but I do not maintain/contribute to pytest so I can't shed light on the issue). Pytest is a fantastic framework (it's even telling you exactly why it can't run your tests): I'm sure they have a good reason for not supporting this behavior.
You claim that you want to:
separate tests and fixtures by different functionalities.
So do that. Separating the test fixtures/functionalities has nothing to do with what you name the files.
I commonly run into this error when splitting up unit/integration/acceptance tests. I split them up so I can run my (fast) unit tests without having to run my (potentially slow) integration/acceptance tests. I might have some module, call it Abc. And I have something like:
tests/
├── unit
│ └── test_abc.py
├── integration
│ └── test_abc.py
But then pytest barfs with the identical error you've shown, and so I just rename integration/test_abc.py to integration/test_abc_integration.py and move on with my day. Like this:
tests/
├── unit
│ └── test_abc.py
├── integration
│ └── test_abc_integration.py
Is it annoying? A little. How long does the fix take? 5 whole seconds.
P.S. You might have to remove __pycache__ directories or you .pyc files for the first run after you get the error you've posted about (if you don't you'll just get the same error again even if you rename).
P.S.S. You can stop the Cpython interpreter (and most others) from writing out __pycache__ and .pyc files by calling python -B -m pytest .... The -B option makes the interpreter not save the bytecode to your filesystem. This results in some performance penalty whenever you run your test suite, but the penalty is usually very small (milage may vary). I typically use this option because I don't like the clutter in my repositories and the performance loss is typically negligible.
I have a package with a directory "tests" in which I'm storing my unit tests. My package looks like:
.
├── LICENSE
├── models
│ └── __init__.py
├── README.md
├── requirements.txt
├── tc.py
├── tests
│ ├── db
│ │ └── test_employee.py
│ └── test_tc.py
└── todo.txt
From my package directory, I want to be able to find both tests/test_tc.py and tests/db/test_employee.py. I'd prefer not to have to install a third-party library (nose or etc) or have to manually build a TestSuite to run this in.
Surely there's a way to tell unittest discover not to stop looking once it's found a test? python -m unittest discover -s tests will find tests/test_tc.py and python -m unittest discover -s tests/db will find tests/db/test_employee.py. Isn't there a way to find both?
In doing a bit of digging, it seems that as long as deeper modules remain importable, they'll be discovered via python -m unittest discover. The solution, then, was simply to add a __init__.py file to each directory to make them packages.
.
├── LICENSE
├── models
│ └── __init__.py
├── README.md
├── requirements.txt
├── tc.py
├── tests
│ ├── db
│ │ ├── __init__.py # NEW
│ │ └── test_employee.py
│ ├── __init__.py # NEW
│ └── test_tc.py
└── todo.txt
So long as each directory has an __init__.py, python -m unittest discover can import the relevant test_* module.
If you're okay with adding a __init__.py file inside tests, you can put a load_tests function there that will handle discovery for you.
If a test package name (directory with __init__.py) matches the
pattern then the package will be checked for a 'load_tests' function. If
this exists then it will be called with loader, tests, pattern.
If load_tests exists then discovery does not recurse into the package,
load_tests is responsible for loading all tests in the package.
I'm far from confident that this is the best way, but one way to write that function would be:
import os
import pkgutil
import inspect
import unittest
# Add *all* subdirectories to this module's path
__path__ = [x[0] for x in os.walk(os.path.dirname(__file__))]
def load_tests(loader, suite, pattern):
for imp, modname, _ in pkgutil.walk_packages(__path__):
mod = imp.find_module(modname).load_module(modname)
for memname, memobj in inspect.getmembers(mod):
if inspect.isclass(memobj):
if issubclass(memobj, unittest.TestCase):
print("Found TestCase: {}".format(memobj))
for test in loader.loadTestsFromTestCase(memobj):
print(" Found Test: {}".format(test))
suite.addTest(test)
print("=" * 70)
return suite
Pretty ugly, I agree.
First you add all subdirectories to the test packages's path (Docs).
Then, you use pkgutil to walk the path, looking for packages or modules.
When it finds one, it then checks the module members to see whether they're classes, and if they're classes, whether they're subclasses of unittest.TestCase. If they are, the tests inside the classes are loaded into the test suite.
So now, from inside your project root, you can type
python -m unittest discover -p tests
Using the -p pattern switch. If all goes well, you'll see what I saw, which is something like:
Found TestCase: <class 'test_tc.TestCase'>
Found Test: testBar (test_tc.TestCase)
Found Test: testFoo (test_tc.TestCase)
Found TestCase: <class 'test_employee.TestCase'>
Found Test: testBar (test_employee.TestCase)
Found Test: testFoo (test_employee.TestCase)
======================================================================
....
----------------------------------------------------------------------
Ran 4 tests in 0.001s
OK
Which is what was expected, each of my two example files contained two tests, testFoo and testBar each.
Edit: After some more digging, it looks like you could specify this function as:
def load_tests(loader, suite, pattern):
for imp, modname, _ in pkgutil.walk_packages(__path__):
mod = imp.find_module(modname).load_module(modname)
for test in loader.loadTestsFromModule(mod):
print("Found Tests: {}".format(test._tests))
suite.addTests(test)
This uses the loader.loadTestsFromModule() method instead of the loader.loadTestsFromTestCase() method I used above. It still modifies the tests package path and walks it looking for modules, which I think is the key here.
The output looks a bit different now, since we're adding a found testsuite at a time to our main testsuite suite:
python -m unittest discover -p tests
Found Tests: [<test_tc.TestCase testMethod=testBar>, <test_tc.TestCase testMethod=testFoo>]
Found Tests: [<test_employee.TestCase testMethod=testBar>, <test_employee.TestCase testMethod=testFoo>]
======================================================================
....
----------------------------------------------------------------------
Ran 4 tests in 0.000s
OK
But we still get the 4 tests we expected, in both classes, in both subdirectories.
The point using init.py, is that one may encounters side effects, like file not being the script file path. Using FOR DOS command can help (not found of DOS commands, but sometimes it helps
setlocal
set CWD=%CD%
FOR /R %%T in (*_test.py) do (
CD %%~pT
python %%T
)
CD %CWD%
endlocal
/R allows for walkthrough the hierarchy from current folder.
(expr) allows for selecting test files (I use _test.py)
%%~pT is $(dirname $T) in shell.
I saved and restore my original directory, as the .bat leaves me where it ends
setlocal ... endlocal to not pollute my environment with CWD.
I'm attempting to implement unit tests as per GAE's Python SDK Setting up a testing framework section.
Using their sample test runner and test, I receive the following output:
Ran 0 tests in 0.000s
OK
I have unittest2 installed and I also tried running the following commands, but all yielded the same response:
python -m unittest discover ~/foldername
python -m unittest2 discover ~/foldername
I tried adding the Basic example test file from Python docs, but also got the same result.
Tried all of above with and without an __init__.py in the unit test's folder.
What should I try next to debug this issue?
Update
My directory structure is as below:
├── app.yaml
├── myclass.py
├── bulkloader.yaml
├── myappname.py
├── index.yaml
├── testmodel.py
├── test_runner.py
└── unit_tests
├── demotestcase.py
└── sample.py
With the contents of both tests from the above referenced links.
Usage: python -m unittest discover [options]
-s directory Directory to start discovery ('.' default)
-p pattern Pattern to match test files ('test*.py' default)