[Aptitude-devel] Bug#642030: aptitude: cannot forbid more than 1 version of a package

[Vincent Lefevre]

On 2015-11-12 21:57:33 +0000, Manuel A. Fernandez Montecelo wrote:
> In your example above, using hold also would not install v2 from
> testing, and when v4 appears, you notice and unhold, and all is well.
> What's the drawback of using Hold in your use-case?

No, when a package is on hold, aptitude does not give any notice
when a new version arrives. That's why I don't like it.

> For example, I had forbidden the versions of LibreOffice in
> experimental, and the resolver still allows me to upgrade to the newer
> versions of LibreOffice in unstable when they arrive (the packages
> show up in "Upgradable", and the version arriving in unstable is
> shown).
[...]

> >> Considering other suites and not only testing and unstable, there
> >> could be v9-2+exp1 appearing soon, not fixing the issue that concerns
> >> the person but with other dangerous/disruptive changes that it is
> >> offered (e.g. depending on a broken version of libimportant), and
> >> v9.2~backport1 could actually fixes the issue and one would like to
> >> install (but ~backport1 makes it to be "smaller" than the given
> >> version, so it would not show).
> >
> > Ditto, aptitude only shows the latest version, so that only v9-2+exp1
> > is visible.
> 
> Nope, it shows the candidate version in the right-most column (e.g.
> the latest in unstable instead of the most recent in experimental,
> unless experimental is pinned higher).

But then, you don't need to forbid versions in experimental.

> > But with Hold, one cannot see when a new version is available.
> 
> The candidate version (not the highest, but the candidate; e.g. the
> latest in unstable instead of the one in experimental) is shown in the
> right-most columns.  Once it reaches a version that you are satisfied
> with, you unhold and it will be allowed to install.

To know whether I am satisfied with some version, I need to know
whether there is a new version. Otherwise the package remains on
hold forever.

> >> There are multiple ways to verify if new versions were released --
> >> curses interface,
> >
> > No, this is not visible with the curses interface.
> 
> It does: when there are newer *candidate* versions it shows in the
> list of packages as "upgradable", it shows the candidate version in
> the right-most column (as I explained above), and all the versions are
> listed in the package info screen.

No, you didn't explain anything. How can I know that the version
is *new*???

> If one considers the bigger picture, forbidding versions or marking on
> hold should be exceptional measures, not something that one does all
> of the time.

I do this many times because packages have major bugs.

> If there is only one bad version that is known to misbehave, OK, one
> forbids that.
> 
> If there are multiple versions that one wants to forbid, then there is
> something seriously wrong with the package (or something needed by the
> current versions that other versions don't provide), so one might as
> well use Hold until the situation clears up.

But one can miss security fixes, which is really bad.

-- 
Vincent Lefèvre <vincent at vinc17.net> - Web: <https://www.vinc17.net/>
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Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)