default dependancy should be python3-powerline

[Scott Palmer]

Test Case
---------
1) sudo apt-get install powerline vim-addon-manager
2) vim-addon-manager install powerline
3) run vim
4) observe the following crash:

Traceback (most recent call last):
  File "<string>", line 4, in <module>
ImportError: No module named 'powerline'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
  File "<string>", line 9, in <module>
ImportError: No module named 'powerline'
An error occurred while importing powerline module.
This could be caused by invalid sys.path setting,
or by an incompatible Python version (powerline requires
Python 2.6, 2.7 or 3.2 and later to work). Please consult
the troubleshooting section in the documentation for
possible solutions.
Unable to import powerline, is it installed?
Press ENTER or type command to continue

With the version of the package from -proposed there will be no Traceback.

Regression Potential
--------------------
Little as we are just adding a recommends which has been added the package since zesty.

Original Description
--------------------
powerline should depend on python3-powerline instead of python-powerline by default for 16.04

ProblemType: BugDistroRelease: Ubuntu 16.04
Package: powerline 2.3-1
ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6
Uname: Linux 4.4.0-21-generic x86_64
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CurrentDesktop: GNOME
Date: Wed Apr 27 10:29:59 2016
InstallationDate: Installed on 2016-04-01 (25 days ago)
InstallationMedia: Ubuntu-GNOME 16.04 LTS "Xenial Xerus" - Beta amd64 (20160323.1)SourcePackage: powerline
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Ralf Heiringhoff (frosty-geek)]

I can confirm that installing python3-powerline after upgrading to 16.04 fixed my problem

[Scott Palmer (skewty)]

This bug is rated medium and it has been over a year.

Here is what I get in Ubuntu 17.10:

$ apt show powerline
Package: powerline
Version: 2.5-1.1
Priority: optional
Section: universe/python
Origin: Ubuntu
Maintainer: Ubuntu Developers <email address hidden>
Original-Maintainer: Jerome Charaoui <email address hidden>
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Installed-Size: 251 kB
Depends: python:any (>= 2.7.5-5~), libc6 (>= 2.4), python-powerline
Recommends: fonts-powerline, python3-powerline
Suggests: python-powerline-doc, vim-addon-manager
Breaks: python-powerline (<< 0~20140216-2)
Replaces: python-powerline (<< 0~20140216-2)
Enhances: awesome, bash, ipython, tmux, vim-nox, zsh
Homepage: https://github.com/Lokaltog/powerline
Download-Size: 42.5 kB
APT-Sources: http://ca.archive.ubuntu.com/ubuntu artful/universe amd64 Packages
Description: prompt and statusline utility
 Powerline is a statusline plugin for vim, and provides statuslines and
 prompts for several other applications, including zsh, bash, tmux,
 IPython, Awesome and Qtile.
 .
 This package contains the Powerline executables.

$ sudo apt install -y python3-powerline
...
$ powerline
The program 'powerline' is currently not installed. You can install it by typing:
sudo apt install powerline
$ sudo apt install -y powerline
...
The following NEW packages will be installed:
  fonts-powerline powerline python-powerline python-psutil
...
$

Is it correct to assume that the desire to move Ubuntu to Python3 in 16.04 has lost almost all of its momentum. If this is indeed still a priority, it would be nice to get this resolved before 18.04.

[TJ (tj)]

In 17.10 it seems the fix was to add to debian/control:

Recommends: python3-powerline

[TJ (tj)]

Was fixed in 17.04 too; the fix wasn't backported/SRU-ed to 16.04 though.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "Add Recommends: python3-powerline" seems to be a debdiff. The ubuntu-sponsors team has been subscribed to the bug report so that they can review and hopefully sponsor the debdiff. If the attachment isn't a patch, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are member of the ~ubuntu-sponsors, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issue please contact him.]

[Brian Murray (brian-murray)]

It's uploaded and awaiting review by an SRU team member.

[Chris J Arges (arges)]

Hello Scott, or anyone else affected,

Accepted powerline into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/powerline/2.3-1ubuntu0 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-xenial to verification-done-xenial. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-xenial. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Brian Murray (brian-murray)]

I installed the version of powerline from -proposed and no longer received the crash with the version of the package in the release pocket.

[Launchpad Janitor (janitor)]

This bug was fixed in the package powerline - 2.3-1ubuntu0

---------------
powerline (2.3-1ubuntu0) xenial; urgency=low

  * debian/control Recommends: python3-powerline to ensure
     vim-nox support (LP: #1575802)

 -- Tj <email address hidden> Wed, 09 Nov 2017 18:25:00 +0000

[Brian Murray (brian-murray)]

The verification of the Stable Release Update for powerline has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

[Scott Palmer (skewty)]

On a fresh 18.04 daily..

$ sudo apt-get install powerline
[sudo] password for scott:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  fonts-powerline libpython-stdlib python python-minimal python-powerline
  python-psutil python2.7 python2.7-minimal python3-powerline python3-psutil
Suggested packages:
  python-powerline-doc vim-addon-manager python-doc python-tk
  python-psutil-doc python2.7-doc binfmt-support
The following NEW packages will be installed:
  fonts-powerline libpython-stdlib powerline python python-minimal
  python-powerline python-psutil python2.7 python2.7-minimal python3-powerline
  python3-psutil
0 upgraded, 11 newly installed, 0 to remove and 0 not upgraded.
Need to get 2,267 kB of archives.
After this operation, 8,242 kB of additional disk space will be used.
Do you want to continue? [Y/n] n
Abort.

scott@scott-home-pc:~$ sudo apt update
Hit:1 http://ca.archive.ubuntu.com/ubuntu bionic InRelease
Hit:2 http://security.ubuntu.com/ubuntu bionic-security InRelease
Hit:3 http://ca.archive.ubuntu.com/ubuntu bionic-updates InRelease
Hit:4 http://ca.archive.ubuntu.com/ubuntu bionic-backports InRelease
Hit:5 http://ca.archive.ubuntu.com/ubuntu bionic-proposed InRelease

$ sudo apt-get install powerline
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  fonts-powerline libpython-stdlib libpython2.7 libpython2.7-minimal
  libpython2.7-stdlib python python-minimal python-powerline python-psutil
  python2.7 python2.7-minimal python3-powerline python3-psutil
Suggested packages:
  python-powerline-doc vim-addon-manager python-doc python-tk
  python-psutil-doc python2.7-doc binfmt-support
The following NEW packages will be installed:
  fonts-powerline libpython-stdlib powerline python python-minimal
  python-powerline python-psutil python2.7 python2.7-minimal python3-powerline
  python3-psutil
The following packages will be upgraded:
  libpython2.7 libpython2.7-minimal libpython2.7-stdlib
3 upgraded, 11 newly installed, 0 to remove and 57 not upgraded.
Need to get 5,564 kB of archives.
After this operation, 8,254 kB of additional disk space will be used.
Do you want to continue? [Y/n]

Will 18.04 not get this update? Why is python2.7 still going to be installed?

[Brian Murray (brian-murray)]

Because powerline depends on python-powerline (the python2 version) and recommends python3-powerline (python3) so both end up getting installed.

 $ apt-cache show powerline
Package: powerline
Architecture: amd64
Version: 2.6-1
Priority: optional
Section: universe/python
Origin: Ubuntu
Maintainer: Ubuntu Developers <email address hidden>
Original-Maintainer: Jerome Charaoui <email address hidden>
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Installed-Size: 251
Depends: python:any (>= 2.7.5-5~), python-powerline
Recommends: fonts-powerline, python3-powerline
...

[Paul White (paulw2u)]

Closing by marking "Fix Released" as per all other bug tasks