port "cask" -- installing prebuilt binaries

[Ken Cunningham]

> On Dec 24, 2020, at 10:58 AM, Jason Liu <jasonliu at umich.edu> wrote:
> 
> A more efficient method that overrides activate/deactivate and does not needlessly de&re&decompress everything would seem useful.
> 
> Since the dmg itself is a compressed archive, it would seem to make sense that activate/deactivate would operate directly on the dmg, no? In other words, the distfile is the archive, so recompressing of the destroot should be skipped entirely. Instead, the dmg distfile should either be copied or moved over to where the activate/deactivate archive usually lives.
> 
> -- 
> Jason Liu


Yes, we have challenges ahead of us sorting this out. For an example, here’s a little tiny Portfile that is supposed to install SageMath. It’s a prime candidate for a “cask” port, and does a fine job of exhibiting the problems to be faced.

Put it in a folder called “binary/sagemath-binary” to see it work, if you like:

===

# -*- coding: utf-8; mode: tcl; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- vim:fenc=utf-8:ft=tcl:et:sw=4:ts=4:sts=4

PortSystem          1.0

name                sagemath-binary
categories          binary math
platforms           darwin
license             Permissive NoMirror
maintainers         nomaintainer
description         free open-source mathematics software system licensed under the GPL
long_description    ${description}. This port installs the binary build from upstream \
                    recommended for this version of MacOS.

homepage            https://www.sagemath.org/index.html

universal_variant   no
archive_sites

# https://www.sagemath.org/download-mac.html
# not all have been listed here
master_sites        http://www.cecm.sfu.ca/sage/osx/intel/ \
                    http://mirrors.mit.edu/sage/osx/intel/ \
                    https://mirror.marwan.ma/sage/osx/intel/ \
                    http://ftp.sun.ac.za/ftp/pub/mirrors/www.sagemath.org/osx/intel/ \
                    https://sagemath.mirror.ac.za/osx/intel/ \
                    http://ftp.leg.uct.ac.za/pub/packages/sage/osx/intel/ \
                    http://ftp.riken.jp/sagemath/osx/intel/ \
                    https://mirrors.tuna.tsinghua.edu.cn/sagemath/osx/intel/ \
                    http://mirror.aarnet.edu.au/pub/sage/osx/intel/ \
                    https://mirror.dogado.de/sage/osx/intel/

# 10.15 and up
if { ${os.platform} eq "darwin" && ${os.major} >= 19  } {
    supported_archs     x86_64 arm64
    version             9.2
    distname            sage-${version}-OSX_10.15.7-x86_64.app
    use_dmg             yes
    checksums           rmd160  398838206e0011ce20a346e78d5db5278e1b2dec \
                        sha256  fa6eb93368d4f7c220cbdd7a1483c1ef9d9b718b0f179c17c2acf14fb74f10c1 \
                        size    1986453988
}

use_configure       no
build {}

destroot {
    copy ${worksrcpath}/SageMath-${version}.app ${destroot}${applications_dir}
    xinstall -m 0640 ${worksrcpath}/README.txt ${destroot}${prefix}/share/${name}-${version}
}

===