Fix searching readline and sqlite3 in FreeBSD

Surprisingly, CPython doesn't search these with pkg-config
This is fixed upstream in 3.12.0a1

plugins/python-build/bin/python-build

@@ -1422,9 +1422,18 @@ use_freebsd_pkg() {
     # check if 11-R or later
     release="$(uname -r)"
     if [ "${release%%.*}" -ge 11 ]; then
-      if pkg info -e readline > /dev/null && ! command -v pkg-config > /dev/null ; then
-        # use readline from Ports Collection
-	# unlike Linux, BSD's cc does not look in /usr/local by default
+      # Use packages from Ports Collection.
+      #
+      # Unlike Linux, BSD's cc does not look in /usr/local by default
+      # where Ports-installed packages are, but they are available via pkg-config.
+      # Surprisingly, CPython's Configure only uses pkg-config
+      # to locate some of the dependencies and not others.
+      # Here we detect those that are (as of this writing) known
+      # to not be searched via pkg-config.
+      #
+      # XXX: As a side effect, this would pick up any other libs from Ports
+      # that are searched via compiler
+      if pkg info -e readline || pkg info -e sqlite3; then
         export CPPFLAGS="${CPPFLAGS:+${CPPFLAGS% } }-I/usr/local/include"
         export LDFLAGS="${LDFLAGS:+${LDFLAGS% } }-L/usr/local/lib -Wl,-rpath,/usr/local/lib"
       fi

plugins/python-build/test/build.bats

@@ -259,6 +259,42 @@ make install
 OUT
 }
 
+@test "readline and sqlite3 are linked from Ports in FreeBSD" {
+  cached_tarball "Python-3.6.2"
+
+  for lib in readline sqlite3; do
+
+    for i in {1..8}; do stub uname '-s : echo FreeBSD'; done
+    stub uname '-r : echo 11.0-RELEASE'
+    for i in {1..2}; do stub uname '-s : echo FreeBSD'; done
+    stub sysctl '-n hw.ncpu : echo 1'
+
+    stub pkg "$([[ $lib == readline ]] && echo "info -e $lib : true" || echo false)"
+    if [[ $lib == sqlite3 ]]; then stub pkg echo "info -e $lib : true"; fi
+
+    stub_make_install
+
+    export -n MAKE_OPTS
+    run_inline_definition <<DEF
+install_package "Python-3.6.2" "http://python.org/ftp/python/3.6.2/Python-3.6.2.tar.gz"
+DEF
+    assert_success
+
+    unstub uname
+    unstub make
+    unstub pkg
+    unstub sysctl
+
+    assert_build_log <<OUT
+Python-3.6.2: CPPFLAGS="-I${TMP}/install/include  -I/usr/local/include" LDFLAGS="-L${TMP}/install/lib -Wl,-rpath=${TMP}/install/lib -L/usr/local/lib -Wl,-rpath,/usr/local/lib" PKG_CONFIG_PATH=""
+Python-3.6.2: --prefix=$INSTALL_ROOT --enable-shared --libdir=$INSTALL_ROOT/lib
+make -j 1
+make install
+OUT
+    rm "$INSTALL_ROOT/build.log"
+  done
+}
+
 @test "no library searches performed during normal operation touch homebrew in non-MacOS" {
   cached_tarball "Python-3.6.2"
 
@@ -502,6 +538,7 @@ OUT
   for i in {1..8}; do stub uname '-s : echo FreeBSD'; done
   stub uname '-r : echo 11.0-RELEASE'
   for i in {1..2}; do stub uname '-s : echo FreeBSD'; done
+  for i in {1..2}; do stub pkg false; done
 
   stub sysctl '-n hw.ncpu : echo 1'
   stub_make_install