[MacPorts] #15395: Use primary port category for fetched distfile layout

[MacPorts]

#15395: Use primary port category for fetched distfile layout
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  Reporter:  wsiegrist at apple.com  |       Owner:  wsiegrist at apple.com       
      Type:  enhancement          |      Status:  new                       
  Priority:  Normal               |   Milestone:  MacPorts base enhancements
 Component:  base                 |     Version:                            
Resolution:                       |    Keywords:  fetch mirror distfiles    
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Changes (by jmr at macports.org):

  * milestone:  => MacPorts base enhancements

Comment:

 Distfiles do tend to stick around in my experience, so I think selfupdate
 will need to rearrange the distfiles directory. Otherwise users would end
 up with distfiles in the wrong place that are not removed by `clean
 --all`.

 Also, this has the side effect of changing the behaviour of dist_subdir.
 Setting it will now only work as expected if all the ports sharing a
 dist_subdir also have the same primary category. Not sure how much of an
 issue this is in practice.

-- 
Ticket URL: <http://trac.macports.org/ticket/15395#comment:1>
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