[MacPorts] #66285: Is it possible to hide ports that cannot be built on this Mac or OS?

[MacPorts]

#66285: Is it possible to hide ports that cannot be built on this Mac or OS?
--------------------------+----------------------------
  Reporter:  ballapete    |      Owner:  (none)
      Type:  enhancement  |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:  2.8.0
Resolution:               |   Keywords:  tiger, leopard
      Port:  MacPorts     |
--------------------------+----------------------------

Comment (by ryandesign):

 You've asked many questions in one ticket; I'll just reply to one of them
 for now.

 Replying to [ticket:66285 ballapete]:
 > `port outdated` lists `xorg-server-devel` although it cannot be
 upgraded. So it is not outdated, it has finished. Why is it listed and why
 is port trying to upgrade it when invoked as `port upgrade outdated`
 although it's not possible? If you can't do anything about it why do you
 mention it?

 MacPorts base doesn't know anything more about the situation than what the
 portfile tells it. In this case, the portfile contains:
 {{{
 platform macosx {
     if {${os.major} < 13} {
         known_fail  yes
         pre-fetch {
             ui_error "$name requires macOS 10.9 or later.  Please use the
 xorg-server-legacy port instead."
             error "unsupported OS version"
         }
     }
 }
 }}}
 Users of 10.8 and earlier should use the xorg-server-legacy port instead,
 but since that's just written as an error message, all MacPorts can do is
 print it for you. The port should be changed to set `replaced_by xorg-
 server-legacy` on 10.8 or earlier so that the replacement happens
 automatically for users.

 I personally favor the portfile development strategy where a single port
 is used for all OS versions, and it changes what software version it
 installs depending on the OS version. But not everyone agrees with me.

 In the more general case where a port simply requires a newer OS and no
 replacement is available for the older OS, MacPorts currently tells you a
 new version is available, but you can't upgrade to it. You're proposing
 that MacPorts base shouldn't tell you about. I'm not sure I agree with
 that. I suppose an argument could be made for that change. But I could
 just as easily see users then asking "Why didn't MacPorts tell me an
 update was available?" The way it is now, at least you're told and update
 is available and you're given the reason why you can't have it.

-- 
Ticket URL: <https://trac.macports.org/ticket/66285#comment:3>
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