Fix Style/RedundantBegin removing comments on assignment statement correction

changelog/fix_style_redundant_being_removing_comments_on_assignment_statement_correction.md

@@ -0,0 +1 @@
+* [#9639](https://github.com/rubocop/rubocop/pull/9639): Fix `Style/RedundantBegin` removing comments on assignment statement correction. ([@marcotc][])

lib/rubocop/cop/style/redundant_begin.rb

@@ -114,6 +114,17 @@ def replace_begin_with_statement(corrector, offense_range, node)
 
           corrector.replace(offense_range, first_child.source)
           corrector.remove(range_between(offense_range.end_pos, first_child.source_range.end_pos))
+
+          restore_removed_comments(corrector, offense_range, node, first_child)
+        end
+
+        # Restore comments that occur between "begin" and "first_child".
+        # These comments will be moved to above the assignment line.
+        def restore_removed_comments(corrector, offense_range, node, first_child)
+          comments_range = range_between(offense_range.end_pos, first_child.source_range.begin_pos)
+          comments = comments_range.source
+
+          corrector.insert_before(node.parent, comments) unless comments.blank?
         end
 
         def empty_begin?(node)

spec/rubocop/cop/style/redundant_begin_spec.rb

@@ -197,14 +197,21 @@ def method
 
   it 'registers and corrects an offense when using `begin` with single statement for or assignment' do
     expect_offense(<<~RUBY)
-      var ||= begin
+      # outer comment
+      var ||= begin # inner comment 1
               ^^^^^ Redundant `begin` block detected.
+        # inner comment 2
         foo
+        # inner comment 3
       end
     RUBY
 
     expect_correction(<<~RUBY)
-      var ||= foo
+      # outer comment
+       # inner comment 1
+        # inner comment 2
+        var ||= foo
+        # inner comment 3
 
     RUBY
   end