1 files changed, 6 insertions, 7 deletions
diff --git a/activesupport/lib/active_support/core_ext/hash/deep_merge.rb b/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
index 24d0a2a481..af771c86ff 100644
--- a/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
+++ b/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
@@ -1,17 +1,16 @@
 class Hash
   # Returns a new hash with +self+ and +other_hash+ merged recursively.
   def deep_merge(other_hash)
-    target = dup
-    other_hash.each_pair do |k,v|
-      tv = target[k]
-      target[k] = tv.is_a?(Hash) && v.is_a?(Hash) ? tv.deep_merge(v) : v
-    end
-    target
+    dup.deep_merge!(other_hash)
   end
 
   # Returns a new hash with +self+ and +other_hash+ merged recursively.
   # Modifies the receiver in place.
   def deep_merge!(other_hash)
-    replace(deep_merge(other_hash))
+    other_hash.each_pair do |k,v|
+      tv = self[k]
+      self[k] = tv.is_a?(Hash) && v.is_a?(Hash) ? tv.deep_merge(v) : v
+    end
+    self
   end
 end