Use a custom cop to check controller action names

SpecificActionNames cop taken from https://github.com/rubocop/rubocop-rails/pull/827

.rubocop.yml

@@ -7,6 +7,7 @@ require:
   - rubocop-performance
   - rubocop-rails
   - rubocop-rake
+  - ./.rubocop/specific_action_names.rb
 
 AllCops:
   TargetRubyVersion: 3.1
@@ -110,3 +111,42 @@ Style/StringLiterals:
 
 Style/SymbolArray:
   EnforcedStyle: brackets
+
+Rails/SpecificActionNames:
+  Description: Use only specific action names.
+  Enabled: true
+  ActionNames:
+    - index
+    - show
+    - new
+    - edit
+    - create
+    - update
+    - destroy
+  Include:
+    - app/controllers/**/*.rb
+  Exclude:
+    # This is a todo list, but is currently too long for `rubocop --auto-gen-config`
+    - 'app/controllers/api/changeset_comments_controller.rb'
+    - 'app/controllers/api/changesets_controller.rb'
+    - 'app/controllers/api/nodes_controller.rb'
+    - 'app/controllers/api/notes_controller.rb'
+    - 'app/controllers/api/old_elements_controller.rb'
+    - 'app/controllers/api/relations_controller.rb'
+    - 'app/controllers/api/user_preferences_controller.rb'
+    - 'app/controllers/api/users_controller.rb'
+    - 'app/controllers/api/ways_controller.rb'
+    - 'app/controllers/browse_controller.rb'
+    - 'app/controllers/changesets_controller.rb'
+    - 'app/controllers/confirmations_controller.rb'
+    - 'app/controllers/diary_comments_controller.rb'
+    - 'app/controllers/diary_entries_controller.rb'
+    - 'app/controllers/directions_controller.rb'
+    - 'app/controllers/errors_controller.rb'
+    - 'app/controllers/export_controller.rb'
+    - 'app/controllers/geocoder_controller.rb'
+    - 'app/controllers/issues_controller.rb'
+    - 'app/controllers/messages_controller.rb'
+    - 'app/controllers/site_controller.rb'
+    - 'app/controllers/traces_controller.rb'
+    - 'app/controllers/users_controller.rb'

.rubocop/specific_action_names.rb

@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module Rails
+      # Use only specific action names.
+      #
+      # It is good practice to separate controller classes rather than adding more actions as needed.
+      # By default, the 7 CRUD action names are specified that are generated by the Rails scaffold.
+      #
+      # @example
+      #   # bad
+      #   class UsersController < ApplicationController
+      #     def articles
+      #     end
+      #   end
+      #
+      #   # good
+      #   class UserArticlesController < ApplicationController
+      #     def index
+      #     end
+      #   end
+      class SpecificActionNames < Base
+        include VisibilityHelp
+
+        MSG = "Use only specific action names."
+
+        # @param node [RuboCop::AST::DefNode]
+        # @return [void]
+        def on_def(node)
+          return unless bad?(node)
+
+          add_offense(
+            node.location.name,
+            :message => format(
+              "Use only specific action names (%<action_names>s).",
+              :action_names => configured_action_names.join(", ")
+            )
+          )
+        end
+
+        private
+
+        # @param node [RuboCop::AST::DefNode]
+        # @return [Boolean]
+        def action?(node)
+          node_visibility(node) == :public
+        end
+
+        # @param node [RuboCop::AST::DefNode]
+        # @return [Boolean]
+        def bad?(node)
+          action?(node) && !configured_action_name?(node)
+        end
+
+        # @param node [RuboCop::AST::DefNode]
+        # @return [Boolean]
+        def configured_action_name?(node)
+          configured_action_names.include?(node.method_name.to_s)
+        end
+
+        # @return [Array<String>]
+        def configured_action_names
+          cop_config["ActionNames"]
+        end
+      end
+    end
+  end
+end