Gemfile in uglifier-0.5.4 vs Gemfile in uglifier-1.0.0

@@ -1,16 +1,25 @@
 source "http://rubygems.org"
-# Add dependencies required to use your gem here.
-# Example:
-#   gem "activesupport", ">= 2.3.5"
 
 gem "execjs", ">=0.3.0"
 gem "multi_json", ">= 1.0.2"
 
-# Add dependencies to develop your gem here.
-# Include everything needed to run rake, tests, features, etc.
+# Depend on defined ExecJS runtime
+execjs_runtimes = {
+  "RubyRacer" => "therubyracer",
+  "RubyRhino" => "therubyrhino",
+  "Mustang" => "mustang"
+}
+
+if ENV["EXECJS_RUNTIME"] && execjs_runtimes[ENV["EXECJS_RUNTIME"]]
+  gem execjs_runtimes[ENV["EXECJS_RUNTIME"]], :group => :development
+end
+
+# Engine
+gem ENV["MULTI_JSON_ENGINE"], :group => :development if ENV["MULTI_JSON_ENGINE"]
+
 group :development do
-  gem "rspec", "~> 2.5.0"
+  gem "rspec", "~> 2.6.0"
   gem "bundler", "~> 1.0.0"
-  gem "jeweler", "~> 1.5.0"
+  gem "jeweler", "~> 1.6.0"
   gem "rcov", ">= 0"
 end