[MacPorts] #39782: Add keyword to list compatible graphical environments (X11, Quartz, Wayland)?

[MacPorts]

#39782: Add keyword to list compatible graphical environments (X11, Quartz,
Wayland)?
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  Reporter:  c.herbig@…   |      Owner:  macports-tickets@…
      Type:  enhancement  |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  base         |    Version:
Resolution:               |   Keywords:
      Port:               |
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Comment (by larryv@…):

 Replying to [ticket:39782 c.herbig@…]:
 > Although some ports list variants like ±x11 and +quartz, some of them
 > don't because the quartz compatibility is handled by a dependency.
 > For example, Gnumeric is +quartz compatible because it is handled by
 > the gtk+quartz dependency, yet there is no indication in the port file
 > that +quartz is an option for gnumeric.

 Does gnumeric actually build differently depending on whether gtk is built
 +quartz or +x11? It is not acceptable for `port install FOO` to produce
 different results based solely on whether a dependency BAR is installed
 +baz or -quux or anything.

 If this is the case, variants need to be added to gnumeric to make its
 builds reproducible. Each variant would use the
 [[source:trunk/dports/_resources/port1.0/group/active_variants-1.1.tcl|active_variants-1.1
 PortGroup]] to ensure that gtk is built with the necessary variant. For an
 example of this idiom, see the
 [[source:trunk/dports/x11/pango/Portfile at 106559#L52|pango Portfile’s
 +quartz variant]]. The PortGroup itself also has rudimentary documentation
 on usage.

 If some degree of intelligence is desired, I believe it is possible to
 check whether a particular dependency is installed with a particular
 variant, and set `default_variants` accordingly.

 > So rather than making a variant in the portfile that does nothing
 > other than to list itself in port info

 The variants should not do nothing. They should check for the presence or
 absence of the relevant dependencies’ variants, as I described above.

 > perhaps it would be wise to make a new keyword (graphics_env ?) that
 > lists the environments that the port is known to work with.  If
 > nothing is specified, then assume X11.  It is not ok to assume that
 > just because the gtk dependency has been compiled for +quartz that the
 > app is though; as of the writing of this, gnome-chemistry-utils fails
 > to build in a +quartz environment due to some X11 specific OpenGL
 > code.

 If gnome-chemistry-utils requires its dependencies to be built as -quartz,
 it should use active_variants-1.1 to enforce this.

 Given that one can (sort of) enforce variant selection on dependencies, I
 don’t see how a new Portfile option meaningfully changes the situation
 here.

-- 
Ticket URL: <https://trac.macports.org/ticket/39782#comment:4>
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