1 files changed, 21 insertions, 15 deletions
diff --git a/activesupport/lib/active_support/hash_with_indifferent_access.rb b/activesupport/lib/active_support/hash_with_indifferent_access.rb
index 2e2ed8a25d..e4afc8af93 100644
--- a/activesupport/lib/active_support/hash_with_indifferent_access.rb
+++ b/activesupport/lib/active_support/hash_with_indifferent_access.rb
@@ -177,20 +177,18 @@ module ActiveSupport
       super(convert_key(key), *extras)
     end
 
-    if Hash.new.respond_to?(:dig)
-      # Same as <tt>Hash#dig</tt> where the key passed as argument can be
-      # either a string or a symbol:
-      #
-      #   counters = ActiveSupport::HashWithIndifferentAccess.new
-      #   counters[:foo] = { bar: 1 }
-      #
-      #   counters.dig('foo', 'bar')     # => 1
-      #   counters.dig(:foo, :bar)       # => 1
-      #   counters.dig(:zoo)             # => nil
-      def dig(*args)
-        args[0] = convert_key(args[0]) if args.size > 0
-        super(*args)
-      end
+    # Same as <tt>Hash#dig</tt> where the key passed as argument can be
+    # either a string or a symbol:
+    #
+    #   counters = ActiveSupport::HashWithIndifferentAccess.new
+    #   counters[:foo] = { bar: 1 }
+    #
+    #   counters.dig('foo', 'bar')     # => 1
+    #   counters.dig(:foo, :bar)       # => 1
+    #   counters.dig(:zoo)             # => nil
+    def dig(*args)
+      args[0] = convert_key(args[0]) if args.size > 0
+      super(*args)
     end
 
     # Same as <tt>Hash#default</tt> where the key passed as argument can be
@@ -228,7 +226,7 @@ module ActiveSupport
     #   hash.fetch_values('a', 'c') # => KeyError: key not found: "c"
     def fetch_values(*indices, &block)
       indices.collect { |key| fetch(key, &block) }
-    end if Hash.method_defined?(:fetch_values)
+    end
 
     # Returns a shallow copy of the hash.
     #
@@ -311,6 +309,14 @@ module ActiveSupport
       dup.tap { |hash| hash.transform_keys!(*args, &block) }
     end
 
+    def transform_keys!
+      return enum_for(:transform_keys!) { size } unless block_given?
+      keys.each do |key|
+        self[yield(key)] = delete(key)
+      end
+      self
+    end
+
     def slice(*keys)
       keys.map! { |key| convert_key(key) }
       self.class.new(super)