Backport Object#public_send to 1.8 so that we can implement Module#delegate such that non-public methods raise

1 files changed, 25 insertions, 0 deletions

diff --git a/activesupport/lib/active_support/core_ext/object/public_send.rb b/activesupport/lib/active_support/core_ext/object/public_send.rb
new file mode 100644
index 0000000000..233e69b4f8
--- /dev/null
+++ b/activesupport/lib/active_support/core_ext/object/public_send.rb
@@ -0,0 +1,25 @@
+require 'active_support/core_ext/kernel/singleton_class'
+
+class Object
+  unless Object.public_method_defined?(:public_send)
+    # Backports Object#public_send from 1.9
+    def public_send(method, *args, &block) # :nodoc:
+      # Don't create a singleton class for the object if it doesn't already have one
+      # (This also protects us from classes like Fixnum and Symbol, which cannot have a
+      # singleton class.)
+      klass = singleton_methods.any? ? self.singleton_class : self.class
+
+      if klass.public_method_defined?(method)
+        send(method, *args, &block)
+      else
+        if klass.private_method_defined?(method)
+          raise NoMethodError, "private method `#{method}' called for #{inspect}"
+        elsif klass.protected_method_defined?(method)
+          raise NoMethodError, "protected method `#{method}' called for #{inspect}"
+        else
+          raise NoMethodError, "undefined method `#{method}' for #{inspect}"
+        end
+      end
+    end
+  end
+end