[Linux] pip install with pep517 fails

[zephyrj]

Linux

• Red Hat Enterprise Linux Server release 7.2 (Maipo)
• psutil-5.6.4

pip --version
pip 19.3.1 from /usr/lib/python2.7/site-packages/pip (python 2.7)

Bug description
The changes made to add pyproject.toml (fc204a9) seem to have stopped pip installs working.

sudo pip install psutil
Collecting psutil
  Using cached https://files.pythonhosted.org/packages/47/ea/d3b6d6fd0b4a6c12984df652525f394e68c8678d2b05075219144eb3a1cf/psutil-5.6.4.tar.gz
  Installing build dependencies ... done
  Getting requirements to build wheel ... error
  ERROR: Command errored out with exit status 1:
   command: /usr/bin/python /usr/lib/python2.7/site-packages/pip/_vendor/pep517/_in_process.py get_requires_for_build_wheel /tmp/tmptckssG
       cwd: /tmp/pip-install-etD7In/psutil
  Complete output (8 lines):
  Traceback (most recent call last):
    File "/usr/lib/python2.7/site-packages/pip/_vendor/pep517/_in_process.py", line 21, in <module>
      import shutil
    File "/usr/lib64/python2.7/shutil.py", line 12, in <module>
      import collections
    File "/usr/lib64/python2.7/collections.py", line 8, in <module>
      from _collections import deque, defaultdict
  ImportError: No module named _collections
  ----------------------------------------

Installing the previous version seems to work correctly:

sudo pip install psutil==5.6.3
Collecting psutil==5.6.3
  Using cached https://files.pythonhosted.org/packages/1c/ca/5b8c1fe032a458c2c4bcbe509d1401dca9dda35c7fc46b36bb81c2834740/psutil-5.6.3.tar.gz
Building wheels for collected packages: psutil
  Building wheel for psutil (setup.py) ... done
  Created wheel for psutil: filename=psutil-5.6.3-cp27-cp27mu-linux_x86_64.whl size=256085 sha256=ddce47f5d86f0bd21bb2b11b90d6ef3ff51353c72d156071c15e1310aac6fe69
  Stored in directory: /root/.cache/pip/wheels/90/7e/74/bb640d77775e6b6a78bcc3120f9fea4d2a28b2706de1cff37d
Successfully built psutil
Installing collected packages: psutil
Successfully installed psutil-5.6.3

It may be related to the following pip issues but I'm not really sure what the upshot of this issue was:
pypa/pip#6163

[gaborbernat]

🤔 this seems to be a pip or python bug; seems importing shutil from within pip breaks the world 🤔 @pfmoore any ideas?

[pfmoore]

Looking at the traceback, it seems to be failing because when the code imports shutil, it tries to import _collections, which isn't working. That's pure stdlib code, so I'd suggest starting by checking if import shutil works in a standard Python prompt.

There may be a pip issue in how the isolated build environment that is getting used in a PEP 517 build gets set up, but I don't know how that code could break the stdlib.

[giampaolo]

I just released a new version without pyproject.toml which should fix this issue. Closing.