EngineDetector.ruby_version should allow dependency injection of version

Author: pitr-ch

lib/concurrent/utility/engine.rb

@@ -39,8 +39,8 @@ def ruby_engine
         defined?(RUBY_ENGINE) ? RUBY_ENGINE : 'ruby'
       end
 
-      def ruby_version(comparison, major, minor = 0, patch = 0)
-        result      = (RUBY_VERSION.split('.').map(&:to_i) <=> [major, minor, patch])
+      def ruby_version(comparison, major, minor, patch, version = RUBY_VERSION)
+        result      = (version.split('.').map(&:to_i) <=> [major, minor, patch])
         comparisons = { :== => [0],
                         :>= => [1, 0],
                         :<= => [-1, 0],