Removing extraneous files on buildbots that block activation

[Joshua Root]

On 2014-12-15 15:46 , David Evans wrote:
> I've seen a number of instances recently on the buildbots where a port
> fails on activation because of extraneous files left in the installation
> tree by some previous failure.
> 
> My most recent example is py27-cython on buildports-snowleopard-x86_64:
>> Error: org.macports.activate for port py27-cython returned: Image error: /opt/local/Library/Frameworks/Python.framework/Versions/2.7/bin/cygdb already exists and does not belong to a registered port.  Unable to activate port py27-cython. Use 'port -f activate py27-cython' to force the activation.
>> DEBUG: Error code: registry::image-error
>> DEBUG: Backtrace: Image error: /opt/local/Library/Frameworks/Python.framework/Versions/2.7/bin/cygdb already exists and does not belong to a registered port.  Unable to activate port py27-cython. Use 'port -f activate py27-cython' to force the activation.
> Typically this is occurs when the activation process is interrupted
> before completion and is fixed by manually forcing the activation and
> removing the offending file(s) that are moved aside in the process.
> 
> Is there any way of fixing these problems on the buildbots as they occur
> (or maybe when the buildbot is restarted) without resorting to manual
> intervention by a sysadmin? 

This more commonly occurs because ports installed directly into $prefix
instead of into ${destroot}${prefix} (this is often caught by sandboxing
now.) So even if that's not what happened here, you could fix it the
same way.

- Josh