dlib: Add Python bindings

math/dlib/Portfile

@@ -5,25 +5,30 @@ PortGroup           github 1.0
 PortGroup           cmake  1.1
 PortGroup           compiler_blacklist_versions 1.0
 
-github.setup        davisking dlib 19.20 v
-homepage            http://dlib.net
+github.setup        davisking dlib 19.21 v
 categories          math
 platforms           darwin
 maintainers         nomaintainer
 license             MIT
 
-description         Modern C++ toolkit for machine learning, image processing, and more.
-long_description    \
-    Dlib is a modern C++ toolkit containing machine learning algorithms and\
-    tools for creating complex software in C++ to solve real world problems. It \
-    is used in both industry and academia in a wide range of domains including \
-    robotics, embedded devices, mobile phones, and large high performance \
-    computing environments. Dlib's open source licensing allows you to use it\
-    in any application, free of charge.
+description         Modern C++ toolkit for machine learning, image \
+                    processing, and more.
+
+long_description    Dlib is a modern C++ toolkit containing machine \
+                    learning algorithms and tools for creating \
+                    complex software in C++ to solve real world \
+                    problems. It is used in both industry and \
+                    academia in a wide range of domains including \
+                    robotics, embedded devices, mobile phones, and \
+                    large high performance computing \
+                    environments. Dlib's open source licensing allows \
+                    you to use it in any application, free of charge.
+
+homepage            http://dlib.net
 
-checksums           rmd160  d9eb9b0e1c40df807f58df5fdee7bdb7cdad56cb \
-                    sha256  733a844f1fa645597d30d8b03d0eee91d7ee066c9f516b12e1a792950fffff68 \
-                    size    10583402
+checksums           rmd160  58abe0906d68ee92936360e8c4c57076bacee75a \
+                    sha256  5895369a1625f833b41bafaf18a5587cbc293eb2f60a1905315441fbd83ecc23 \
+                    size    10587515
 
 compiler.cxx_standard   2011
 compiler.thread_local_storage yes
@@ -33,3 +38,47 @@ compiler.blacklist-append {clang < 800}
 
 configure.cxxflags-append -fvisibility=hidden -fvisibility-inlines-hidden
 cmake.build_type    Release
+
+# create Python subports
+set python_versions {37 38}
+foreach v ${python_versions} {
+    subport py${v}-${github.project} {
+        PortGroup   python 1.0
+        python.default_version  ${v}
+    }
+}
+
+# Python bindings for supported Python versions
+if {[string match "py*" ${subport}]} {
+    categories-append   math
+    description     Python ${python.branch} bindings for ${description}
+    long_description\
+                    This package provides Python ${python.branch}\
+                    bindings, modules, and scripts.
+
+    depends_lib-append \
+                    port:sqlite3
+
+    depends_build-append \
+                    port:py${python.version}-setuptools
+
+    depends_test-append \
+                    port:py${python.version}-pytest
+
+    build.dir       ${worksrcpath}
+    build.post_args
+
+    destroot.target install
+
+    post-destroot {
+        set docdir ${prefix}/share/doc/${subport}
+        xinstall -d ${destroot}${docdir}
+        xinstall -m 0644 -W ${worksrcpath} README.md \
+            ${destroot}${docdir}
+    }
+
+    test.run        yes
+    test.env        PYTHONPATH=[glob -nocomplain ${worksrcpath}/build/lib*]
+
+    livecheck.type  none
+}