CYTHON : Generating coverage for pyx file

Question

I am trying to generate code coverage report for a cython module, an d facing issues.

I have a simple c++ code : apple.h and apple.cpp files. The cpp file is simple as :

using namespace std;
namespace mango {
    apple::apple(int key) {
            _key = key;
    };
    int apple::execute()
    {
            return _key*_key;
    };
}

I have written a basic cython code over this in "cyApple.pyx" :

# cython: linetrace=True
from libcpp.list cimport list as clist
from libcpp.string cimport string
from libc.stdlib cimport malloc

cdef extern from "apple.h" namespace "mango" :
    cdef cppclass apple:
            apple(int)
            int execute()
cdef class pyApple:
    cdef apple* aa
    def __init__(self, number):
            self.aa = new apple(number)

    def  getSquare(self):
            return self.aa.execute()

My setup.py file :

from distutils.core import setup, Extension
from Cython.Build import cythonize

compiler_directives = {}
define_macros = []

compiler_directives['profile'] = True
compiler_directives['linetrace'] = True
define_macros.append(('CYTHON_TRACE', '1'))

setup(ext_modules = cythonize(Extension(
       "cyApple",
       sources=["cyApple.pyx", "apple.cpp"],
       define_macros=define_macros,
       language="c++",
  ), compiler_directives=compiler_directives))

This generates a proper library cyApple.so. I have also written a simple appletest.py file to run test cases :

import cyApple, unittest
class APPLETests(unittest.TestCase):
    def test1(self):
            temp = 5
            apple1 = cyApple.pyApple(temp)
            self.assertEqual(25, apple1.getSquare())
suite = unittest.TestLoader().loadTestsFromTestCase(APPLETests)
unittest.TextTestRunner(verbosity=3).run(suite)

The test works fine. The problem is I need to get code coverage for my cyApple.pyx file

When i run "coverage report -m" I get the error and coverage for only my test file not pyx file.

cyApple.pyx   NotPython: Couldn't parse '/home/final/cyApple.pyx' as Python source: 'invalid syntax' at line 2
Name           Stmts   Miss  Cover   Missing
--------------------------------------------
appletest.py       8      1    88%   9

I tried to look online and get some help , so i added
.coveragerc file with contents as :

[run]
plugins = Cython.Coverage

On running "coverage run appletest.py" i get errors :

...
... 
...
ImportError: No module named Coverage

I want to generate simple code coverage report for my pyx file. How i can do it in a simple way ?

I reinstalled Cython-0.28.3. Now on running "coverage run appletest.py" I am getting error :

test1 (__main__.APPLETests) ... Segmentation fault (core dumped)

This is my apple.h file :

#include<iostream>
namespace mango {
class apple {
public:

    apple(int key);
    int execute();
private:
    int _key;
};
}

Answer 1

You must update Cython. The documentation states:

Since Cython 0.23, line tracing (see above) also enables support for coverage reporting with the coverage.py tool.