Added a deprecation warning when using BUILD_WITH_GEO_LIBRARIES or installing pygdal

bin/steps/gdal

@@ -22,6 +22,10 @@ source "$BIN_DIR/utils"
 if (pip-grep -s requirements.txt GDAL gdal pygdal &> /dev/null) then
 
   if [ ! -f ".heroku/vendor/bin/gdalserver" ]; then
+
+    puts-warn "The vendored GDAL package in the Heroku Python Buildpack now deprecated."
+    puts-warn "To enable GDAL use an alternative buildpack is available here - https://github.com/heroku/heroku-geo-buildpack"
+
     echo "-----> Noticed GDAL. Bootstrapping gdal."
     mkdir -p .heroku/vendor
     # Download and extract cryptography into target vendor directory.

bin/steps/geo-libs

@@ -24,6 +24,9 @@ source "$BIN_DIR/utils"
 if [[ "$BUILD_WITH_GEO_LIBRARIES" ]]; then
   mcount "buildvar.BUILD_WITH_GEO_LIBRARIES"
 
+  puts-warn "The GDAL, GEOS and PROJ binaries and BUILD_WITH_GEO_LIBRARIES functonality are now deprecated."
+  puts-warn "An alternative buildpack to enable GDAL, GEOS and PROJ use is available here - https://github.com/heroku/heroku-geo-buildpack"
+
   if [ ! -f ".heroku/vendor/bin/proj" ]; then
     echo "-----> Bootstrapping gdal, geos, proj."
     mkdir -p .heroku/vendor

test/run-deps

@@ -23,6 +23,13 @@ testGEOS() {
   assertCapturedSuccess
 }
 
+testGEOSDeprecation() {
+  export BUILD_WITH_GEO_LIBRARIES=1
+  compile "geos"
+  assertCaptured "The GDAL, GEOS and PROJ binaries and BUILD_WITH_GEO_LIBRARIES functionality are now deprecated."
+  assertCapturedSuccess
+}
+
 testNLTK() {
   # NOTE: This is a RuntimeWarning emitted by Python 3's runpy.py script
   # which is what is used when you call `python -m <module>`. This is due to