[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 ryandesign):

 I found [https://www.imagemagick.org/discourse-
 server/viewtopic.php?t=32622 this discussion] from Fedora Linux about the
 problems they faced after they upgraded to ImageMagick 7. Ultimately,
 following the recommendation of the developers of ImageMagick, they
 downgraded back to version 6. Granted that discussion was 2 years ago so
 opinions may have changed since then. But ImageMagick 6 remains supported
 until 2027.

 That discussion did point out something I didn't know or had forgotten,
 which is that whereas ImageMagick 6 has a range of programs including
 `convert` and `mogrify`, ImageMagick 7 has only a `magick` program. So
 there may be fewer naming conflicts than I thought.

 I have not tried to install ImageMagick 7 so I don't know if there is a
 naming conflict with its pkg-config files. If there is, we could delete
 the unversioned .pc files and patch all programs that use ImageMagick to
 use a versioned .pc file.

 If there are any remaining naming conflicts between 6 and 7, the problem
 with offering an ImageMagick_select port to deal with that is that any
 current port that uses ImageMagick that has not been patched or configured
 properly, or any new port that uses ImageMagick that is added to MacPorts
 in the future, could inadvertently use the version of ImageMagick that the
 user has selected, rather than the one that was intended.

-- 
Ticket URL: <https://trac.macports.org/ticket/51310#comment:19>
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