[MacPorts] #30739: selfupdate should sync last not first

[MacPorts]

#30739: selfupdate should sync last not first
-------------------------------------+--------------------------------------
 Reporter:  ryandesign@…             |       Owner:  macports-tickets@…                   
     Type:  defect                   |      Status:  new                                  
 Priority:  Normal                   |   Milestone:                                       
Component:  base                     |     Version:  2.0.1                                
 Keywords:                           |        Port:                                       
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 selfupdate syncs the ports tree and then builds the new version of
 MacPorts. Which means that you've got a new ports tree, full of ports that
 have new MacPorts 2.0 commands, trying to be parsed by MacPorts 1.9.2,
 failing, generating tons of errors while trying to build the new
 portindex:

 {{{
 Adding port textproc/xercesc3
 Failed to parse file textproc/xmlcatmgr/Portfile: invalid command name
 "installs_libs"
 Adding port textproc/xmlresume2x
 Failed to parse file textproc/xmlto/Portfile: invalid command name
 "installs_libs"
 Adding port www/ZendFramework
 }}}

 selfupdate should first update base, then sync the ports tree with that
 new version of base. Or if it's not possible to relaunch itself, then it
 should exit after updating base and tell the user to run selfupdate again.

-- 
Ticket URL: <https://trac.macports.org/ticket/30739>
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