FFe: pylint 2

[Benjamin Drung]

pylint < 2.0 does not work with Python 3.7 at all (see bug #1785080). To support Python 3.7, pylint and the astroid library needs to be updated to >= 2.0. The major upstream release drops Python 2 support. Therefore we agreed on following keep compat with python2 while supporting 3.7 in https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=902631

astroid: uses the 2.x branch, builds only python3-astroid
pylint: uses the 2.x branch, builds only pylint3, pylint-doc
NEW astroid2: remains on the 1.x branch, builds only python-astroid
NEW pylint2: remains on the 1.x branch, builds only pylint (depending on python-astroid)

This bug report is requesting a feature freeze exception for implementing it. This will upgrade pylint3 and python3-astroid to version >= 2.0 to support Python 3.7 while keeping the Python 2 version unchanged (but introducing new source packages).

There are some packages that use pylint in their tests suites while building (e.g. devscripts).

[Łukasz Zemczak (sil2100)]

Seems like quite a change. I see that it's still not done in Debian. I know the approach has been generally approved but I would feel better knowing that we won't divert unnecessarily from Debian here if some name change or similar suddenly still pops up.
Also, to properly assess this FFe we'd also need the rest of documentation [1], more particularly some build logs on cosmic making sure both the new packages and updated old ones build correctly + upgrade logs to make sure the upgrade works with no issues.

[1] https://wiki.ubuntu.com/FreezeExceptionProcess

[Benjamin Drung (bdrung)]

As documented in Debian bug #902631, astroid was split into src:astroid2/1.6.5-2 (for Python 2) and src:astroid/2.0.4-1 (for Python 3). So we could sync these versions from Debian without changes.

[Benjamin Drung (bdrung)]

This is now done in Debian (except the pylint2 source):

astroid2=1.6.5-2
astroid=2.0.4-2
pylint=2.1.1-1

[Benjamin Drung (bdrung)]

astroid2=1.6.5-2 is already in cosmic.

I uploaded astroid=2.0.4-2 and pylint=2.1.1-1 to my PPA (see the build logs there):
https://launchpad.net/~bdrung/+archive/ubuntu/ppa

[Jeremy Bícha (jbicha)]

astroid and astroid2 have already been updated in cosmic.

[Benjamin Drung (bdrung)]

I tested pylint3 2.1.1-1 on a bunch of Python project and it works fine there.

[Mattia Rizzolo (mapreri)]

at any rate, pylint 2 is now in release, so I guess this can be closed…

;-)