[Bug 1616953] Re: dpkg --compare-versions comparison incorrect for some package versions

[Adam Conrad]

Debian Policy says that the "Debian revision" follows the *last* minus
sign, not the first.  So, you think your Debian revisions are
-0ubuntu1-0 and -0ubuntu1-0, when in reality they're both -0.

As such, you're comparing upstream parts of: 1.3.1+16-0ubuntu1 and
1.3.1-0ubuntu1, without breaking on the dash, and it turns out those
sort in an order you didn't expect.  A relevant shorter test case is:

(base)adconrad at nosferatu:~$ dpkg --compare-versions 1.2.3+4 gt 1.2.3-4
(base)adconrad at nosferatu:~$ echo $?
0
(base)adconrad at nosferatu:~$ dpkg --compare-versions 1.2.3+4-0 gt 1.2.3-4-0
(base)adconrad at nosferatu:~$ echo $?
1

Basically, + sorts lower than -, when it's not a special separator
between upstream and Debian revisions.  This isn't a bug, just a poor
understanding of policy.

** Changed in: dpkg (Ubuntu)
       Status: New => Invalid

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to dpkg in Ubuntu.
https://bugs.launchpad.net/bugs/1616953

Title:
  dpkg --compare-versions comparison incorrect for some package versions

Status in dpkg package in Ubuntu:
  Invalid

Bug description:
  I have a situation where dpkg --compare-versions is reporting the
  wrong status for certain package versions.

  A simple example:

  $ dpkg --compare-versions 1.3.1+16-0ubuntu1-0 gt 1.3.1-0ubuntu1-0
  $ echo $?
  1

  It is the second '-' in the second version that is triggering this.
  The first version should be greater than the second.

  I spoke w/ Ken VanDine about this and he agreed that this looks like a
  bug.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/dpkg/+bug/1616953/+subscriptions