id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	difficulty
1100	chicken-install uninstalls eggs on updating	Mario Domenech Goulart		"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The following installed extensions are outdated, because `awful-static-pages' requires later versions: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.
"	defect	closed	minor	5.0	core tools	4.8.x	fixed	chicken-install, update		medium