port upgrade --force shouldn't uninstall if no permission was given to install a missing dependency

[RJVB (René Bertin)]

This is a rare situation, that gave rise to a port being uninstalled in error, I consider:

Given: a port "A" that has a build dependency on port "B1" which itself conflicts with port "B2". Once built, port "A" can co-exist with either "B1" or "B2"; in fact, "A" has a path-style *runtime* dependency on an executable provided by both B1 and B2 (path:bin/bb).

Scenario (leaving out sudo, and ignoring the reasons why I proceeded this way):

> port deactivate B2
> port activate B1
> port destroot A
> port deactivate B1
> port activate B2
> port -nv upgrade --force A
--->  Computing dependencies for A..
The following dependencies will be installed:  B1
Continue? [Y/n]: n
--->  Deactivating A @version
--->  Uninstalling A @version
--->  Cleaning A
--->  Removing work directory for A
--->  Computing dependencies for A..
The following dependencies will be installed:  B1
Continue? [Y/n]: n
--->  Scanning binaries for linking errors

I consider that the process should have been aborted when I first refused to install B1. One could also consider that

• the depends_build dependency should be ignored since the build process has been completed
• the depends_run dependency is satisfied by the presence of ${prefix}/bin/bb (provided by B2 at the time).

So in a sense there should be no missing dependency when doing an upgrade .

[ryandesign (Ryan Carsten Schmidt)]

I agree that if you answer "no" to the "Continue?" prompt, MacPorts should abort and not do anything.