[Nix-dev] Nix-env bugs

[Eelco Dolstra]

Hi,

On 04/06/2011 11:45 AM, Lluís Batlle i Rossell wrote:

>>> it seems nix-env --upgrade is broken. I'm not sure if this was always
>>> like that (my version is 1.0pre26015) but it is certainly clashing
>>> with the man page. It offers downgrades by default and -A doesn't work
>>> at all. For example, nix-env -u \* says upgrading `python-2.7.1' to
>>> `python-2.4.6' (that is very old python!).
>>
>> This is probably because all the other Pythons were marked as low
>> priority.  It just so happens that I merged the modular-python
>> branch today, which gets rid of all old Python versions.  So this
>> problem should be gone now.
>
> What has the lowPrio to do with "-u" wanting to *upgrade* 2.7.1 to 2.4.6?
> Hasn't "-u" a strict definition based on names and version numbers?

Actually it also takes priority into account.  It will upgrade lower priority 
packages to higher priority packages.  Since the installed 2.7.1 was marked as 
"lowPrio", 2.4.6 is considered a "better" version, so nix-env -u will upgrade to 
it.

To prevent packages from being upgraded, you can set the "keep" flag:

$ nix-env --set-flag keep true python

-- 
Eelco Dolstra | http://www.st.ewi.tudelft.nl/~dolstra/