Fix AS::OrderHash#select and #reject on Ruby 2.1.1+

In Ruby 2.1.1 and later select and reject return a new instance of
Hash rather than the subclass so we need to override them to return
an instance of the correct class.

2 files changed, 18 insertions, 0 deletions

diff --git a/activesupport/lib/active_support/ordered_hash.rb b/activesupport/lib/active_support/ordered_hash.rb
index b0d4f2bd86..e81bd013b6 100644
--- a/activesupport/lib/active_support/ordered_hash.rb
+++ b/activesupport/lib/active_support/ordered_hash.rb
@@ -52,6 +52,20 @@ module ActiveSupport
       true
     end
 
+    if RUBY_VERSION > '2.1.0'
+      # On Ruby 2.1.1 and later the behavior of .select and reject changed to
+      # return a new Hash instance so we need to override them to return an
+      # instance of the correct class.
+
+      def select(*args, &block)
+        dup.tap { |hash| hash.select!(*args, &block) }
+      end
+
+      def reject(*args, &block)
+        dup.tap { |hash| hash.reject!(*args, &block) }
+      end
+    end
+
     # Hash is ordered in Ruby 1.9!
     if RUBY_VERSION < '1.9'
 
diff --git a/activesupport/test/ordered_hash_test.rb b/activesupport/test/ordered_hash_test.rb
index a7fd9402c8..bbaccf2594 100644
--- a/activesupport/test/ordered_hash_test.rb
+++ b/activesupport/test/ordered_hash_test.rb
@@ -125,6 +125,9 @@ class OrderedHashTest < Test::Unit::TestCase
 
   def test_select
     assert_equal @keys, @ordered_hash.select { true }.map(&:first)
+    new_ordered_hash = @ordered_hash.select { true }
+    assert_equal @keys, new_ordered_hash.map(&:first)
+    assert_instance_of ActiveSupport::OrderedHash, new_ordered_hash
   end
 
   def test_delete_if
@@ -147,6 +150,7 @@ class OrderedHashTest < Test::Unit::TestCase
     assert_equal copy, @ordered_hash
     assert !new_ordered_hash.keys.include?('pink')
     assert @ordered_hash.keys.include?('pink')
+    assert_instance_of ActiveSupport::OrderedHash, new_ordered_hash
   end
 
   def test_clear