Add jruby.gem.(path|home) property support for rubygems. (Take 2)

Fix for JRUBY-4729.

Signed-off-by: Nick Sieger <nick@nicksieger.com>

lib/ruby/site_ruby/1.8/rubygems/defaults/jruby.rb

@@ -1,4 +1,5 @@
 require 'rubygems/config_file'
+require 'rbconfig'
 
 module Gem
 
@@ -22,7 +23,9 @@ def set_paths(gpaths)
 
     alias_method :original_default_path, :default_path
     def default_path
-      paths = original_default_path
+      paths = RbConfig::CONFIG["default_gem_path"]
+      paths = paths.split(':').reject {|p| p.empty? }.compact if paths
+      paths ||= original_default_path
       @jar_paths = paths.select {|p| jarred_path? p }
       paths.reject {|p| jarred_path? p }
     end
@@ -51,7 +54,9 @@ def jarred_path?(p)
   # JRuby: We don't want gems installed in lib/jruby/gems, but rather
   # to preserve the old location: lib/ruby/gems.
   def self.default_dir
-    File.join ConfigMap[:libdir], 'ruby', 'gems', '1.8'
+    dir = RbConfig::CONFIG["default_gem_home"]
+    dir ||= File.join(ConfigMap[:libdir], 'ruby', 'gems', '1.8')
+    dir
   end
 
   ##

src/org/jruby/libraries/RbConfigLibrary.java

@@ -206,6 +206,12 @@ public void load(Ruby runtime, boolean wrap) {
         if (runtime.is1_9()) {
             setConfig(configHash, "ridir", new NormalizedFile(shareDir, "ri").getPath());
         }
+
+        // These will be used as jruby defaults for rubygems if found
+        String gemhome = SafePropertyAccessor.getProperty("jruby.gem.home");
+        String gempath = SafePropertyAccessor.getProperty("jruby.gem.path");
+        if (gemhome != null) setConfig(configHash, "default_gem_home", gemhome);
+        if (gempath != null) setConfig(configHash, "default_gem_path", gempath);
 
         RubyHash mkmfHash = RubyHash.newHash(runtime);