[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 michaelld@…):

 OK; good discussion that I can follow / parse & I'm glad for it. Given the
 lateness of me getting to this tonight, I'm going to put my proposals here
 -briefly- for 1 last round of comments & wait to do the formal commits
 until Tuesday (morning in US/Eastern preferably).

 A) Here's what I'm proposing to do tomorrow:

 0) commit the minimal patch to allow qt4-mac to install into libexec (just
 change qt_dir to be "${prefix}/libexec/qt4");[[BR]]
 1) commit the proposed (minimal) patch to qt4-mac that allows it to work
 with 10.11.[[BR]]
 These will bring qt4-mac into a state where it works on most target OS X
 versions but especially with 10.11 as well as allowing for parallel
 installs. It's not perfect, but it gets things moving & does not require
 more testing/evaluation. We will have enough work getting Qt4 dependent
 ports working with the parallel build that I don't think we need more
 things to deal with just right now.[[BR]]
 2) rev-bump ports that are known to work with the updated qt4-mac.

 B) I then propose that we create a qt4-mac-devel port that René owns (via
 his current email) with me and openmaintainer. He can do lots of awesome
 things with it (Portfile, patches, main repo, whatever), and folks who are
 brave enough can use it as a drop-in augmented replacement for qt4-mac
 (yes?). When features reach a state of acceptance / maturity in qt4-mac-
 devel, they can be ported to qt4-mac en mass; or, if it works well enough,
 we just use it instead of qt4-mac. In this manner, we get to test drive
 René's mods while not burdening folks who use qt4-mac & don't really care
 about all the cool stuff going on under the hood.

 C) I further propose that since Qt4 is EOL except for security updates, we
 just use René Qt4 github repo as the master branch for fixes / patches for
 qt4-mac-devel. In this way, we can avoid all of the patches that have made
 qt4-mac so !@#$ difficult to maintain in the past. And, René maintains
 control over what's in and what's out, with advice from us; and pull
 requests from us or anybody.

 I'm guessing that doing all of the above will actually be a 2-step
 process. The first step is 0 through 2; I don't want to wait any longer to
 fix qt4-mac on 10.11, and it makes sense to do the parallel install at the
 same time. The second step will be doing B and C, and whatever changes are
 required to qt4-mac to allow it and qt4-mac-devel to be hot-swappable
 replacements; these will probably require a rev-bump to qt4-mac, but I
 think that's a fair trade-off for getting functionality in place ASAP then
 making it robust once we've verified that it all works.

-- 
Ticket URL: <https://trac.macports.org/ticket/44193#comment:74>
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