[Fix rubocop#1143] Fix an error for `Rails/RedundantActiveRecordAllMe…

…thod`

Fixes rubocop#1143.

This PR fixes an error for `Rails/RedundantActiveRecordAllMethod`
when using RuboCop 1.51 or lower.

changelog/fix_an_error_for_rails_redundant_active_record_all_method.md

@@ -0,0 +1 @@
+* [#1143](https://github.com/rubocop/rubocop-rails/issues/1143): Fix an error for `Rails/RedundantActiveRecordAllMethod` when using RuboCop 1.51 or lower. ([@koic][])

lib/rubocop/cop/rails/redundant_active_record_all_method.rb

@@ -172,6 +172,35 @@ def possible_enumerable_block_method?(node)
         def offense_range(node)
           range_between(node.loc.selector.begin_pos, node.source_range.end_pos)
         end
+
+        # TODO: In the future, please support only RuboCop 1.52+ and use `RuboCop::Cop::AllowedReceivers`:
+        #       https://github.com/rubocop/rubocop/blob/v1.52.0/lib/rubocop/cop/mixin/allowed_receivers.rb
+        #       At that time, this duplicated module implementation can be removed.
+        module AllowedReceivers
+          def allowed_receiver?(receiver)
+            receiver_name = receiver_name(receiver)
+
+            allowed_receivers.include?(receiver_name)
+          end
+
+          def receiver_name(receiver)
+            return receiver_name(receiver.receiver) if receiver.receiver && !receiver.receiver.const_type?
+
+            if receiver.send_type?
+              if receiver.receiver
+                "#{receiver_name(receiver.receiver)}.#{receiver.method_name}"
+              else
+                receiver.method_name.to_s
+              end
+            else
+              receiver.source
+            end
+          end
+
+          def allowed_receivers
+            cop_config.fetch('AllowedReceivers', [])
+          end
+        end
       end
     end
   end