[MacPorts] #44193: qt: allow side by side installation of qt4-mac and qt5-mac

[MacPorts]

#44193: qt: allow side by side installation of qt4-mac and qt5-mac
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  Reporter:  mojca@…           |      Owner:  mcalhoun@…
      Type:  enhancement       |     Status:  new
  Priority:  Normal            |  Milestone:
 Component:  ports             |    Version:
Resolution:                    |   Keywords:
      Port:  qt4-mac, qt5-mac  |
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Comment (by rjvbertin@…):

 I have already identified a (surprisingly!) few ports that are ill-behaved
 and will break (corrected versions are available), and I'll be more than
 willing to help with other fallout. Provided of course that the transition
 is based on my work, and that at least some of my other changes are taken
 into consideration too. Off the top of my hat, there are the exception-
 less build (reducing overhead and bringing qt4 on the same page as qt5 in
 that aspect), the patches for improved font style support, and those
 improving the KDE4 experience. And there is the return of the sqlite3
 plugin back into the main port of course, so that one doesn't have to
 install an auxilliary port before being able to test all of the few end-
 user applications qt4-mac installs (Bradley's suggestion, and I fully
 agree with it).

 I have a fully working qt4-mac-devel port that can be used for testing
 right now, with the changes to the PortGroup done in such a way that they
 do not interfere with the current installation. In other words, it detects
 if qt4-mac was installed in what I call "exclusive" mode and sets up the
 environment appropriately. If so required, I can modify it such that this
 is the default more also when building qt4-mac itself, for now.
 My qt4-mac-devel port also has a subport that allows anyone to install it
 WITHOUT having to rebuild all qt4 dependents (and that one has been tested
 thoroughly because I myself didn't want to have to go through such a full
 rebuild while testing).

 Isn't there something like a buildbot that could be set to run a rebuild
 of all the dependent ports without forcing them upon the world, in order
 to take stock of the fallout? Bradley (pixilla) has been asking me for
 such an action. As I said elsewhere, I'm not sure if it's really up to the
 qt4-mac maintainer(s) (and/or Bradley and me) to do this kind of thing,
 but I also see no issue with it provided we can use an existing
 infrastructure to (re)build all dependents without first having to
 identify and install them more or less by hand (and on a VM that I think
 severely under-resourced for the purpose).

-- 
Ticket URL: <https://trac.macports.org/ticket/44193#comment:35>
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