is_wheel fails when source_directory is None about pip-accel

[xolox]

Hi Federico,

Thanks for the detailed bug report! I can reproduce the issue: Without the constraints file everything works as expected but when the constraints file is given on the command line pip's internal behavior changes in a way that I didn't anticipate. I'll investigate how I can fix this.

[FedericoRessi]

@xolox Indeed the problem is using requirements file and devstack uses it every-where to assure having the right set of dependencies installed. I looks like attribute source_dir of one InstallationRequirement instance is None. I don't know if this is a type of value that has to be expected or if this because of another problem happening before when parsing requirements test file.
Thank you in advance. I you need help please let me know.

[xolox]

I just published pip-accel 0.37.1 which should resolve the issue you reported. Can you try it out and confirm whether the issue is resolved for you?

[FedericoRessi]

I am going to test it and let you know. Thanks

[FedericoRessi]

It works!

[xolox]

Thanks for the confirmation and good to hear that it works now!