dvisvgm: add devel port and rearrange accordingly with whitespace tweaks

graphics/dvisvgm/Portfile

@@ -1,54 +1,96 @@
 # -*- 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
-PortGroup           cxx11 1.1
-PortGroup           github 1.0
-
-github.setup        mgieseki dvisvgm 2.7
-checksums           rmd160 8ab80a1b75679bacd4926a0155ee205b322c1b88 \
-                    sha256 c8276b5780f5a9aee6ab475449bcb7fd4e27b780f4e5525902238a5b88c3edf7 \
-                    size   3037242
-revision            1
-
-categories          graphics textproc
-platforms           darwin
-license             GPL-3+
-maintainers         {michaelld @michaelld} openmaintainer
-
-description         DVI to SVG converter
-long_description    The command-line utility dvisvgm is a tool for TeX/LaTeX users. It \
-                    converts DVI files to the XML-based scalable vector graphics format SVG.
-
-github.tarball_from releases
-
-depends_build       port:asciidoc \
-                    port:pkgconfig
-
-depends_lib         port:brotli \
-                    port:freetype \
-                    port:ghostscript \
-                    port:potrace \
-                    port:texlive-bin \
-                    port:woff2 \
-                    port:zlib
+PortSystem       1.0
+PortGroup        cxx11 1.1
+PortGroup        github 1.0
+
+name             dvisvgm
+categories       graphics textproc
+platforms        darwin
+license          GPL-3+
+maintainers      {michaelld @michaelld} openmaintainer
+
+description      DVI to SVG converter
+long_description ${description}. The command-line utility dvisvgm is a tool \
+    for TeX/LaTeX users. It converts DVI files to the XML-based scalable \
+    vector graphics format SVG.
+
+subport dvisvgm-devel {}
+
+if {${subport} eq ${name}} {
+
+    github.setup mgieseki dvisvgm 2.7
+    checksums    rmd160 8ab80a1b75679bacd4926a0155ee205b322c1b88 \
+                 sha256 c8276b5780f5a9aee6ab475449bcb7fd4e27b780f4e5525902238a5b88c3edf7 \
+                 size   3037242
+    revision     1
+
+    # github.tarball_from releases
+    conflicts    ${name}-devel
+
+    long_description ${description}: \
+        This port follows the release version of ${name}, which is typically \
+        updated every 6 months. If for some reason this port does not build or \
+        function as desired, try the ${name}-devel port.
+
+    # temporary patch to move some c++14 features back to c++11 or
+    # earlier. This patch comes from upstream.
+    patchfiles-append patch-fix-make_array.diff
+    patch.pre_args -p1
+
+} else {
+
+    # devel
+
+    github.setup mgieseki dvisvgm 6e826ebfc9b9fc5e40ff81782348c9d3bded042f
+    version      20190415-[string range ${github.version} 0 7]
+    checksums    rmd160 184b78514fc7241e1e2ae6d859928aef4b1a6bde \
+                 sha256 a492cede98d46ac7839a8edde00f6a183ee7ec88a41f564840d5470788d8e178 \
+                 size   2556452
+    revision     0
+
+    conflicts    ${name}
+    long_description ${description}: \
+        This port follows the GIT master version of ${name}, which is typically \
+        updated every few days to weeks.
+
+    use_autoconf yes
+    autoconf.cmd ${worksrcpath}/autogen.sh
+
+    # Setting autoconf.cmd to a non-default value after setting 'use_autoconf yes'
+    # removes the automatic dependencies, so re-add them.
+    depends_build \
+        port:autoconf \
+        port:automake \
+        port:libtool
+
+}
+
+depends_build \
+    port:asciidoc \
+    port:pkgconfig
+
+depends_lib \
+    port:brotli \
+    port:freetype \
+    port:ghostscript \
+    port:potrace \
+    port:texlive-bin \
+    port:woff2 \
+    port:zlib
 # dvisvgm also depends on xxhash which is not yet packaged by MacPorts
 # but the dependency is bundled with the sources & taken from there
-#                   port:xxhash
-
-# temporary patch to move some c++14 features back to c++11 or
-# earlier. This patch comes from upstream.
-patchfiles-append patch-fix-make_array.diff
-patch.pre_args -p1
+#   port:xxhash
 
 # prevent opportunistic dependency on gawk
 configure.env-append \
-                    AWK=/usr/bin/awk
+    AWK=/usr/bin/awk
 
 # see https://trac.macports.org/ticket/57528
-use_parallel_build  no
+use_parallel_build no
 
-test.run            yes
-test.target         check
+test.run    yes
+test.target check
 
 pre-activate {
     if {![catch {set vers [lindex [registry_active texlive-bin-extra] 0]}]