Invisible prompts in do-release-upgrade

I was right. The code does print("Continue? [yN] ", end="") and then sys.stdin.readline() with no flush in between.

Here's a suggested patch for trusty's update-release-upgrader. I haven't tested it (since I already upgraded my 14.04 to 14.10). It also needs to be forward-ported to later versions so this bug won't regress.

I think this kind of UI glitch merits a SRU.

The attachment "suggested patch" 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.]

Thanks for the bug/patch! I've uploaded to vivid, will open a task for trusty

Uploaded fixes for trusty and utopic, will unsub sponsors and sub sru team.

This bug was fixed in the package ubuntu-release-upgrader - 1:15.04.4

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ubuntu-release-upgrader (1:15.04.4) vivid; urgency=medium

  * DistUpgrade/DistUpgradeViewText.py:
    - flush stdout before reading user input. (LP: #1417880)
 -- Marius Gedminas <email address hidden> Wed, 04 Feb 2015 09:45:06 -0500

Hello Marius, or anyone else affected,

Accepted ubuntu-release-upgrader into trusty-proposed. The package will build now and be available at http://launchpad.net/ubuntu/+source/ubuntu-release-upgrader/1:0.220.7 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 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 to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. 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!

Hello Marius, or anyone else affected,

Accepted ubuntu-release-upgrader into utopic-proposed. The package will build now and be available at http://launchpad.net/ubuntu/+source/ubuntu-release-upgrader/1:14.10.10 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 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 to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. 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!

I've verified do-release-upgrade on utopic (version 1:14.10.10). I haven't actually completed the upgrade, just checked that both prompts (the SSH continue prompt and the package detail prompt) show up before canceling.

This bug was fixed in the package ubuntu-release-upgrader - 1:14.10.10

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ubuntu-release-upgrader (1:14.10.10) utopic; urgency=medium

  * DistUpgrade/DistUpgradeViewText.py:
    - flush stdout before reading user input. (LP: #1417880)
 -- Marius Gedminas <email address hidden> Wed, 04 Feb 2015 10:29:39 -0500

The updated package finally reached Rackspace's Ubuntu mirror and I tried to verify it on my 14.04 cloud VM. Unfortunately the bug is still present in ubuntu-release-upgrader 1:0.220.7 from trusty-proposed.

I can see that the new sys.stdout.flush() line is present in /usr/lib/python3/dist-packages/DistUpgrade/DistUpgradeViewText.py of the updated package, so I'm baffled as to what's going on. Will try to investigate.

Any modifications I make to /usr/lib/python3/dist-packages/DistUpgrade/DistUpgradeViewText.py (such as inserting debug print statements) do not take effect.

Is do-release-upgrade actually executing code downloaded from the Internet? Looks like it is.

'DEBUG_UPDATE_MANAGER=1 do-release-upgrade -d' shows me it's downloading a gpg-signed tarball from http://mirror.rackspace.com/ubuntu//dists/utopic/main/dist-upgrader-all/current/utopic.tar.gz, which has an older copy of DistUpgradeViewText.py, without my fix.

Modification times shown at http://archive.ubuntu.com/ubuntu//dists/utopic/main/dist-upgrader-all/current/ indicate that the main archive also lacks this fix.

Right, d-r-u in trusty uses utopic's, utopic uses vivid's, etc. (Well, more to the point, they use the tarball for the target series).

So, when you were testing utopic, you were actually testing vivid, and when testing trusty, you're testing pre-fix utopic.

In light of that general annoyance in reproducing and validating this, I think I'll just do a by-hand validation of the 1-line patch itself and release, and you can reopen the bug if it proves to still be broken after the tarballs are updated.

This bug was fixed in the package ubuntu-release-upgrader - 1:0.220.7

---------------
ubuntu-release-upgrader (1:0.220.7) trusty; urgency=medium

  * DistUpgrade/DistUpgradeViewText.py:
    - flush stdout before reading user input. (LP: #1417880)
 -- Marius Gedminas <email address hidden> Wed, 04 Feb 2015 10:49:34 -0500

> you can reopen the bug if it proves to still be broken after the tarballs are updated.

When can I expect the tarballs to be updated? http://archive.ubuntu.com/ubuntu//dists/utopic/main/dist-upgrader-all/current/ still has timestamps from Oct 2014. Does this bug need an Utopic task?

(I suppose at some point Utopic will be retired and do-release-upgrade for 14.04 will start using vivid's dist-upgrader where this is fixed, so perhaps I should stop worrying about it.)