[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):

 V6 and v7 are NOT compatible at either the API or command line levels.  I
 believe that dropping v7 in place of v6 would result in a huge amount of
 repair work.  The good news is that v7 was made to coexist with v6.
 Library names, include files, and command lines appear to mostly be
 unique.  There are a few conflicts which I think can be easily worked out.
 That is why I asked earlier about conflicts.  I recommend:

     1.  Leave the current v6 port alone, for the most part.
     2.  Create a new port **ImageMagick7**.
     3.  Fix conflicts as they arise.

 For example, most IM command-line commands appear to be unique between
 versions.  The unmodified v6 versions will continue to "just work".
 However, the command **magick-script** seems to conflict between versions.
 I am unsure how to resolve.  Either the v6 or v7 version could be
 disabled.  Alternatively the v6 version could be renamed to e.g.
 **magick6-script** on the notion that usage is rare, then fix v6 port
 problems as they arise.  Check IM history; this particular scenario was
 probably solved long ago by someone else.  My general idea is to get the
 v7 port going first, then work on conflicts later.  Yes I know, some
 conflicts will not wait.  "Just deal with it."

-- 
Ticket URL: <https://trac.macports.org/ticket/51310#comment:77>
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