Bug#257747: Let 'I' (InstallSingle) pull in required upgrades

[Andrew Pimlott <andrew@pimlott.net>]

On Tue, Jul 06, 2004 at 12:53:04PM -0400, Daniel Burrows wrote:
>   I had the impression you were complaining because "I" is doing
> something different from "aptitude install foo"...but it really
> is doing the same thing.

I don't understand what you are saying.  I gave an example of how they
are not doing the same thing.

> > Also, it should be easy to reproduce the problem without mixing
> > releases.  Just install unstable, wait until there are a bunch of
> > upgrades available, then go into aptitude and press 'I' on an upgrade
> > that depends upon another upgrade.  Same behavior.
> 
>   No.  The problem is that release mixing is not handled well;

I assure you:  You can reproduce the behavior without mixing releases.
I just can't give an example, because I'd have to wait until right
upgrades are available.  Here is an example scenario:

    - I have a pure unstable system with package p1 at version 1.
    - I 'u'pdate, and a bunch of new and upgraded packages are
      available.  In particular, there is package p1 version 2, and
      package p2 that depends upon package p1 (>= 2).
    - I press 'I' on p2.  It will show broken, because it needs a newer
      version of p1, but p1 has been placed on hold by 'I'.

>   apt only
> looks at the default release when automatically resolving dependencies.
> See, eg, #167398...or try the same thing with apt-get ("apt-get install
> cream/unstable").

That is one issue, but not the problem I am talking about.  My issue is
that aptitude refuses to un-hold packages implicitly put on hold by 'I'.
I'm saying that the "hold" that 'I' puts packages on should mean "hold
unless an explicit install/upgrade of another package requires it to be
upgraded".  (Or, it could be a new command, and 'I' could be left the
same.)

>   The problem is that you have to do this recursively and handle a
> number of weird cases.  apt already does this, it just doesn't handle
> mixed releases very well.

I'm sure there are problems with it, but apt-get and aptitude at the
command line handle it well enough, in my experience (as shown by my
example).  So the code I want is in apt, in some form.  Maybe not in a
form that is usable for aptitude, however.

Andrew