Easiest way of unit testing C code with Python

Question

I've got a pile of C code that I'd like to unit test using Python's unittest library (in Windows), but I'm trying to work out the best way of interfacing the C code so that Python can execute it (and get the results back). Does anybody have any experience in the easiest way to do it?

Some ideas include:

• Wrapping the code as a Python C extension using the Python API
• Wrap the C code using SWIG
• Add a DLL wrapper to the C code and load it into Python using ctypes
• Add a small XML-RPC server to the c-code and call it using xmlrpclib (yes, I know this seems a bit far-out!)

Is there a canonical way of doing this? I'm going to be doing this quite a lot, with different C modules, so I'd like to find a way which is least effort.

Answer 1

Using ctypes would be my first instinct, though I must admit that if I was testing C code that was not going to be interfaced from Python in the first place, I would just use check. Check has the strong advantage of being able to properly report test cases that segfault. This is because it runs each test case in a separate process.

Now if you are going to create a python wrapper for the C code anyway, I would simply unittest the wrapper. In addition to the methods you listed above, you could also use Cython to write such a wrapper with python-like code and then unittest it from Python.