Fix an incorrect autocorrect for Style/RedundantDoubleSplatHashBraces

Fixes standardrb/standard#505.

This PR fixes an incorrect autocorrect for `Style/RedundantDoubleSplatHashBraces`
using double splat in double splat hash braces.

changelog/fix_an_incorrect_autocorrect_for_style_redundant_double_splat_hash_braces.md

@@ -0,0 +1 @@
+* [#11392](https://github.com/rubocop/rubocop/pull/11392): Fix an incorrect autocorrect for `Style/RedundantDoubleSplatHashBraces` using double splat in double splat hash braces. ([@koic][])

lib/rubocop/cop/style/redundant_double_splat_hash_braces.rb

@@ -30,7 +30,7 @@ def on_hash(node)
           return unless double_splat_hash_braces?(grandparent)
 
           add_offense(grandparent) do |corrector|
-            corrector.replace(grandparent, node.pairs.map(&:source).join(', '))
+            corrector.replace(grandparent, node.children.map(&:source).join(', '))
           end
         end
       end

spec/rubocop/cop/style/redundant_double_splat_hash_braces_spec.rb

@@ -12,6 +12,17 @@
     RUBY
   end
 
+  it 'registers an offense when using double splat in double splat hash braces' do
+    expect_offense(<<~RUBY)
+      do_something(**{foo: bar, **options})
+                   ^^^^^^^^^^^^^^^^^^^^^^^ Remove the redundant double splat and braces, use keyword arguments directly.
+    RUBY
+
+    expect_correction(<<~RUBY)
+      do_something(foo: bar, **options)
+    RUBY
+  end
+
   it 'does not register an offense when using keyword arguments' do
     expect_no_offenses(<<~RUBY)
       do_something(foo: bar, baz: qux)