1 files changed, 6 insertions, 12 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 f92a2f1c2a..9bc50b7bc6 100644
--- a/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
+++ b/activesupport/lib/active_support/core_ext/hash/deep_merge.rb
@@ -21,20 +21,14 @@ class Hash
 
   # Same as +deep_merge+, but modifies +self+.
   def deep_merge!(other_hash, &block)
-    other_hash.each_pair do |current_key, other_value|
-      this_value = self[current_key]
-
-      self[current_key] = if this_value.is_a?(Hash) && other_value.is_a?(Hash)
-        this_value.deep_merge(other_value, &block)
+    merge!(other_hash) do |key, this_val, other_val|
+      if this_val.is_a?(Hash) && other_val.is_a?(Hash)
+        this_val.deep_merge(other_val, &block)
+      elsif block_given?
+        block.call(key, this_val, other_val)
       else
-        if block_given? && key?(current_key)
-          block.call(current_key, this_value, other_value)
-        else
-          other_value
-        end
+        other_val
       end
     end
-
-    self
   end
 end