status of python3 sage on distros

[Antonio Rojas]

Hi all,

 Following up on [1], after fixing ipython 7 issues I was able to run the full test suite of sage built against latest python3 system packages (many of which are ahead of their py2 counterparts). Fortunately, the situation is not as bad as I expected, here is a summary of the (distro-specific) issues:

- ipython 7: requires major changes which are not backwards compatible since the preparsing framework has been completely rewritten. Tracked at https://trac.sagemath.org/ticket/28197

- sphinx 2.2: docs fail to build due to an obsolete sphinx.ext.autodoc.inspector import that no longer exists. I opened https://trac.sagemath.org/ticket/28453 to remove it, please review. Besides this, some tests are failing due to a deprecation warning: 

   /usr/share/doc/sage/common/themes/sage/search.html:22: RemovedInSphinx30Warning: To modify script_files in the theme is deprecated. Please insert a <script> tag directly in your theme instead.

 I have no idea what this means or how to fix it.

- matplotlib 3: causes one test failure due to a warning - the affected test seems to be quite broken even on current py2 (but it's only noticeable in the plot itself so the test suite misses it) - I've opened https://trac.sagemath.org/ticket/28449 to track it.

- networkx 2.3: some failures due to a removed parameter in the closeness_centrality method. Easily fixable in a backwards compatible way, I've opened https://trac.sagemath.org/ticket/28450

- rpy 3.x: lots of failures due to a single renamed method (ri2py -> rpy2py). Could be fixed in a backwards compatible way by using an alias, but I don't know if its worth the effort if python2 support will be dropped soon. Patch is at [2]

[1] https://groups.google.com/forum/#!topic/sage-packaging/i9VosTO9-cM

[2] https://aur.archlinux.org/cgit/aur.git/tree/sagemath-rpy-3.patch?h=sagemath-python3-gitHi all,