Support for different rubies

Author: waterlink

lib/contracts/engine.rb

@@ -14,7 +14,7 @@ class << self
       # .apply(klass)      - enables contracts engine on klass
       # .applied?(klass)   - returns true if klass has contracts engine
       # .fetch_from(klass) - returns contracts engine for klass
-      delegate [:apply, :applied?, :fetch_from] => :base_engine
+      def_delegators :base_engine, :apply, :applied?, :fetch_from
 
       private
 

lib/contracts/engine/base.rb

@@ -121,7 +121,7 @@ def eigenclass
       end
 
       def eigenclass_engine
-        Engine.fetch_from(eigenclass)
+        Eigenclass.lift(eigenclass, klass)
       end
 
       def decorators

lib/contracts/engine/eigenclass.rb

@@ -6,6 +6,22 @@ class Eigenclass < Base
       # Class that owns this eigenclass
       attr_accessor :owner_class
 
+      # Automatically enables eigenclass engine if it is not
+      # Returns its engine
+      # NOTE: Required by jruby in 1.9 mode. Otherwise inherited
+      # eigenclasses don't have their engines
+      #
+      # @param [Class] eigenclass - class in question
+      # @param [Class] owner - owner of eigenclass
+      # @return [Engine::Eigenclass]
+      def self.lift(eigenclass, owner)
+        return Engine.fetch_from(eigenclass) if Engine.applied?(eigenclass)
+
+        Target.new(eigenclass).apply(Eigenclass)
+        Engine.fetch_from(owner).set_eigenclass_owner
+        Engine.fetch_from(eigenclass)
+      end
+
       # No-op for eigenclasses
       def set_eigenclass_owner
       end