[MacPorts] #51310: ImageMagick: update to 7.x

[MacPorts]

#51310: ImageMagick: update to 7.x
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  Reporter:  mopihopi     |      Owner:  ryandesign
      Type:  update       |     Status:  assigned
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:               |   Keywords:
      Port:  ImageMagick  |
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Comment (by Dave-Allured):

 Here is something else to explore.  That is a long list of MacPorts ports
 that depend on ImageMagick.  Separate into two lists:
 * ImageMagick is a library dependency.
 * ImageMagick is only a runtime dependency, and nothing else.
 I have a hunch that the runtime dependent ports may be easy to fix, or
 just work with no changes.  The one port that I know about uses the
 "convert" command and nothing else, if I remember correctly.

 Watch out for port files that have mislabeled ImageMagick as a library
 dependency when they only use it as a runtime dependency, i.e don't link
 and just use it in command mode only.  I have seen this kind of thing
 before.

-- 
Ticket URL: <https://trac.macports.org/ticket/51310#comment:42>
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