Limit Array#extract_options! to directl instances of Hash and HWIA. Add extractable_options? to Hash so that subclasses of Hash can opt-into extractable behavior. This fixes an issue where respond_with wasn't working with subclasses of Hash that were provided by other libraries (such as CouchDB or Mashie) [#4145 state:resolved]

1 files changed, 16 insertions, 1 deletions

diff --git a/activesupport/lib/active_support/core_ext/array/extract_options.rb b/activesupport/lib/active_support/core_ext/array/extract_options.rb
index 9ca32dc7aa..40ceb3eb9e 100644
--- a/activesupport/lib/active_support/core_ext/array/extract_options.rb
+++ b/activesupport/lib/active_support/core_ext/array/extract_options.rb
@@ -1,3 +1,14 @@
+class Hash
+  # By default, only instances of Hash itself are extractable.
+  # Subclasses of Hash may implement this method and return
+  # true to declare themselves as extractable. If a Hash
+  # is extractable, Array#extract_options! pops it from
+  # the Array when it is the last element of the Array.
+  def extractable_options?
+    instance_of?(Hash)
+  end
+end
+
 class Array
   # Extracts options from a set of arguments. Removes and returns the last
   # element in the array if it's a hash, otherwise returns a blank hash.
@@ -9,6 +20,10 @@ class Array
   #   options(1, 2)           # => {}
   #   options(1, 2, :a => :b) # => {:a=>:b}
   def extract_options!
-    last.is_a?(::Hash) ? pop : {}
+    if last.is_a?(Hash) && last.extractable_options?
+      pop
+    else
+      {}
+    end
   end
 end