[Chicken-janitors] #1100: chicken-install uninstalls eggs on updating

[Chicken Trac]

#1100: chicken-install uninstalls eggs on updating
-------------------------------------+--------------------------------------
 Reporter:  mario                    |       Owner:         
     Type:  defect                   |      Status:  new    
 Priority:  minor                    |   Milestone:  someday
Component:  core tools               |     Version:  4.8.x  
 Keywords:  chicken-install, update  |  
-------------------------------------+--------------------------------------
 When we install an egg X that depends on a certain version of egg Y, and
 we have a version of egg Y installed, but not the minimum version required
 by X, chicken-installs prompts for an update.  If we decide to update Y to
 the version required by X, chicken-install first ''uninstalls'' Y.

 This is dangerous.  If for any reason Y or any egg in the dependencies
 chain of Y fail (it has to be reinstalled, after all), we end up in a
 situation worse than we were before installing X, since, besides not
 installing X, Y was removed.

 Here's a practical example:

 {{{
 checking dependencies for `awful-static-pages' ...

 The following installed extensions are outdated, because `awful-static-
 pages' requires later versions:
   awful (0.39.2 -> 0.40.0)

 Do you want to replace the existing extensions? (yes/no/abort) yes
  upgrade: awful
 removing previously installed extension `awful' ...
   rm -fr '/home/mario/local/chicken-4.8.2/lib/chicken/7/awful.so'
   rm -fr '/home/mario/local/chicken-4.8.2/lib/chicken/7/awful.import.so'
   rm -fr '/home/mario/local/chicken-4.8.2/lib/chicken/7/awful.setup-info'

 ...
 }}}

 What if the installation of the new awful fails?

 This situation can be potentially more dangerous if the CHICKEN
 installation is old.  Testing new egg versions against old CHICKEN
 versions is not usual, so they are much more prone to breakage.

-- 
Ticket URL: <http://bugs.call-cc.org/ticket/1100>
CHICKEN Scheme <http://www.call-with-current-continuation.org/>
CHICKEN Scheme is a compiler for the Scheme programming language.