Cython dependency

[mrmagooey]

Hi,

Currently if I have a requirements.txt file like so:

Cython==0.24.1
python-afl==0.5.3

And I try to install it with pip install -r requirements.txt it will fail because there are Cython checks in the setup.py, and Cython is not available until after pip install has completed.

Any chance these Cython checks could be taken out (and maybe put elsewhere), and possibly have Cython added as a dependency in the distutils setup call?

[jwilk]

Thanks for the bug report.

The root cause is that Python packaging ecosystem is completely insane.

To declare dependencies you'd have to use setuptools, which has nasty habits of installing stuff behind your back and ruining your sys.path.
And then pip doesn't support build-dependencies: pypa/pip#1820

Anyway, I implemented work-around in b5bc99f.
I'll make a new release and upload it to PyPI later today.

[jwilk]

You will still get scary warnings about missing Cython, but the installation should ultimately succeed:

$ pip install /path/to/python-afl/
Processing /path/to/python-afl
Collecting Cython>=0.19 (from python-afl===0.5.4)
  Downloading Cython-0.24.1-cp27-cp27mu-manylinux1_x86_64.whl (5.9MB)
    100% |################################| 5.9MB 60kB/s 
Building wheels for collected packages: python-afl
  Running setup.py bdist_wheel for python-afl ... error
  Complete output from command /usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-11uhku-build/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" bdist_wheel -d /tmp/tmp9lKgOlpip-wheel- --python-tag cp27:
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
    File "/tmp/pip-11uhku-build/setup.py", line 80, in <module>
      raise RuntimeError('Cython >= 0.19 is required')
  RuntimeError: Cython >= 0.19 is required

  ----------------------------------------
  Failed building wheel for python-afl
  Running setup.py clean for python-afl
  Complete output from command /usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-11uhku-build/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" clean --all:
  Traceback (most recent call last):
    File "<string>", line 1, in <module>
    File "/tmp/pip-11uhku-build/setup.py", line 80, in <module>
      raise RuntimeError('Cython >= 0.19 is required')
  RuntimeError: Cython >= 0.19 is required

  ----------------------------------------
  Failed cleaning build dir for python-afl
Failed to build python-afl
Installing collected packages: Cython, python-afl
  Running setup.py install for python-afl ... done
Successfully installed Cython python-afl

[jwilk]

Fixed in python-afl 0.5.4.