root5: ImportError about __builtin__ on Python 3

[cdeil (Christoph Deil)]

I installed root5 +python34 on Mac OS X 10.10. Trying to import ROOT in Python gives this error:

$ python -c 'import ROOT'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/ROOT.py", line 341, in <module>
    import __builtin__
ImportError: No module named '__builtin__'

Is this a ROOT bug or a problem with how it's configured in Macports?

[larryv (Lawrence Velázquez)]

There is no __builtin__ module in Python 3.4; you probably want builtins.

• ​https://docs.python.org/2.7/library/__builtin__.html
• ​https://docs.python.org/3/library/builtins.html

[cdeil (Christoph Deil)]

So it's a Python 3 bug in ROOT.py and should be reported to the ROOT devs? Can someone reproduce this issue inside or outside Macports?

Here's the ROOT.py that was installed by Macports on my system: ​https://gist.github.com/cdeil/93a9234c2556478d674a#file-root-py-L328

[cjones051073 (Chris Jones)]

Python 3 is not really supported by upstream, I know this from previous discussions. It compiles, but I can reproduce what you see. Please do report upstream, although I am not sure what response you will get..

Chris

[cdeil (Christoph Deil)]

I filed an issue in the ROOT tracker: ​https://sft.its.cern.ch/jira/browse/ROOT-6898

Python 3 and ROOT has worked for me in the past years, so either it's a recent regression or a configuration problem.

[mojca (Mojca Miklavec)]

The upstream ticket seems to suggest that the issue was fixed. Is that true?

Can we also add support for python3.5 to both root5 and root6?

[cjones051073 (Chris Jones)]

I *think* I tried python 3.5 a while back and it did not work, but perhaps things have changed since....

By all means add it as an option, its just another number in a list ;)

[mojca (Mojca Miklavec)]

I added the python35 variant to root5 in r143654 and import ROOT seems to work inside python3.5, I didn't do any more extensive tests (I'm not sure how to do them), so I'm considering this particular issue resolved.

It would be nice to add that variant to root6 as well, but Python3 is broken there at the moment anyway (#50066), so testing is not really possible.

I'm closing this ticket.