not possible to use "Repair broken packages"

See also the following ubuntu-release-upgrader bug LP: #1798872.

We probably should sanity check all of python, python2, python3; not just the most recent one. The python sanity checking exists to make sure pyclean and friends work and don't cause a ton of upgrade failure reports.

I think that's actually the same bug as the one I just opened: bug 1800823, but as mentioned, the solution should cover all python symlinks and not just python3.

To further expand on the "all symlinks":

> [Regression Potential]
> The code is just being updated to use python3 instead of python so there isn't any change of a regression.

That's wrong. You can now clearly symlink python to python3 (or 2.6) and you'd get a ton of errors from postinsts.

This bug was fixed in the package ubuntu-release-upgrader - 1:19.04.1

---------------
ubuntu-release-upgrader (1:19.04.1) disco; urgency=medium

  * DistUpgrade/{EOL,Devel}ReleaseAnnouncement,
    DistUpgrade/window_main.ui,
    data/gtkbuilder/DistUpgrade.ui,
    data/DistUpgrade.cfg,
    pre-build.sh:
    - updated for 18.10 -> 19.04
  * DistUpgrade/DistUpgradeController.py: check all the python symlinks and
    versions instead of the python one. Thanks to juliank for the assistance.
    (LP: #1799839)
  * do-release-upgrade: Do not block release upgrades if the installable
    updates are ones which are not fully phased. (LP: #1799710)

 -- Brian Murray <email address hidden> Wed, 31 Oct 2018 15:14:25 -0700

Hello Brian, or anyone else affected,

Accepted ubuntu-release-upgrader into cosmic-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/ubuntu-release-upgrader/1:18.10.11.1 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-cosmic to verification-done-cosmic. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-cosmic. In either case, without details of your testing we will not be able to proceed.

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

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

Hello Brian, or anyone else affected,

Accepted ubuntu-release-upgrader into bionic-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/ubuntu-release-upgrader/1:18.04.28 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-bionic to verification-done-bionic. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-bionic. In either case, without details of your testing we will not be able to proceed.

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

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

I installed the version of ubuntu-release-upgrader from -proposed on an Ubuntu 18.10 system then rebooted into recovery mode and was able to successfully launch "repair broken packages".

I tested this on Ubuntu 18.04 and while the original test case did not fail, the version of ubuntu-release-upgrader from -proposed also works. I think it is worth installing this update as it is an improvement and checks both python and python3 and we don't know what kind of crazy things people do to their systems.

This bug was fixed in the package ubuntu-release-upgrader - 1:18.04.28

---------------
ubuntu-release-upgrader (1:18.04.28) bionic; urgency=medium

  * DistUpgrade/DistUpgradeController.py: check all the python symlinks and
    versions instead of the python one. Thanks to juliank for the assistance.
    (LP: #1799839)
  * do-release-upgrade: Do not block release upgrades if the installable
    updates are ones which are not fully phased. (LP: #1799710)

 -- Brian Murray <email address hidden> Thu, 01 Nov 2018 10:17:43 -0700

This bug was fixed in the package ubuntu-release-upgrader - 1:18.10.11.1

---------------
ubuntu-release-upgrader (1:18.10.11.1) cosmic; urgency=medium

  * DistUpgrade/DistUpgradeController.py: check all the python symlinks and
    versions instead of the python one. Thanks to juliank for the assistance.
    (LP: #1799839)
  * do-release-upgrade: Do not block release upgrades if the installable
    updates are ones which are not fully phased. (LP: #1799710)

 -- Brian Murray <email address hidden> Wed, 31 Oct 2018 16:15:17 -0700

The verification of the Stable Release Update for ubuntu-release-upgrader 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.