Running C unit tests with Pytest
p403n1x87.github.io
Running C unit tests with Pytest
1–10 of 44 posts
Re: Running C unit tests with Pytest
#2I doubt that it's pytest-specific, but the idea of using a unit test tool to explore a new problem space and build up to working product is powerful.
Maybe not so much in the UX space, but for ETL and back-end work, I'm a fan.
Re: Running C unit tests with Pytest
#3 @pytest.fixture
def libfact():
yield CDLL("./fact.so")
That gets more relevant when on-the-fly compilation is added to the mix, spawning a compiler for every test is a complete waste of time.
Re: Running C unit tests with Pytest
#4Shameless self-plug since I recently made a small header-only C testing "framework":
https://github.com/rubenvannieuwpoort/c_unit_tests
Feels a bit more in line with the spirit of C (small language, few dependencies).
Re: Running C unit tests with Pytest
#5How would you go to do this for c++? Specifically for classes and templates, is there an easy way to call code without having to manually write the demangled names of the functions?
Re: Running C unit tests with Pytest
#6@pytest.fixture def libfact(): yield CDLL("./fact.so") FWIW that's pretty confusing as it gives the impression the library is reloaded for every test, but iirc dlopen() will just return a handle to the existing one. I don't think ctypes has a good way to unload dlls so it should probably be `fixture(scope='session')`. That gets more relevant when on-the-fly compilation is added to the mix, spawning a compiler for eve…
You can use tempfiles and (on OSX) use the private API of ctypes to dlclose to close the handle. Different call on Windows I think. Something like
import _ctypes
import shutil
import tempfile
@pytest.fixture
def libfact():
tmp = tempfile.NamedTemporaryFile(delete=True)
shutil.copy2("./fact.so", tmp.name)
lib = CDLL(tmp.name)
yield lib
_ctypes.dlclose(lib.handle)
Re: Running C unit tests with Pytest
#7How would you go to do this for c++? Specifically for classes and templates, is there an easy way to call code without having to manually write the demangled names of the functions?
[deleted]
Re: Running C unit tests with Pytest
#8@pytest.fixture def libfact(): yield CDLL("./fact.so") FWIW that's pretty confusing as it gives the impression the library is reloaded for every test, but iirc dlopen() will just return a handle to the existing one. I don't think ctypes has a good way to unload dlls so it should probably be `fixture(scope='session')`. That gets more relevant when on-the-fly compilation is added to the mix, spawning a compiler for eve…
You can use tempfiles and (on OSX) use the private API of ctypes to dlclose to close the handle. Different call on Windows I think. Something like import _ctypes import shutil import tempfile @pytest.fixture def libfact(): tmp = tempfile.NamedTemporaryFile(delete=True) shutil.copy2("./fact.so", tmp.name) lib = CDLL(tmp.name) yield lib _ctypes.dlclose(lib.handle) EDIT: fixed error mentioned in reply.
Did you mean to have the `tmp.name` as the library passed into `CDDL`? If not, what’s the purpose of the copy?
Re: Running C unit tests with Pytest
#9Earlier quoted context omitted.
You can use tempfiles and (on OSX) use the private API of ctypes to dlclose to close the handle. Different call on Windows I think. Something like import _ctypes import shutil import tempfile @pytest.fixture def libfact(): tmp = tempfile.NamedTemporaryFile(delete=True) shutil.copy2("./fact.so", tmp.name) lib = CDLL(tmp.name) yield lib _ctypes.dlclose(lib.handle) EDIT: fixed error mentioned in reply.
Did you mean to have the `tmp.name` as the library passed into `CDDL`? If not, what’s the purpose of the copy?
Yes! Thank you. Fixed it.
Re: Running C unit tests with Pytest
#10this seems cool, but... brittle? especially embedding build steps in python.
i've used check in the past and was happy enough with it, it didn't take long to learn. all unit test frameworks are basically the same at their core.
interop between c and python with ctypes is fun though.