1 files changed, 46 insertions, 4 deletions
diff --git a/rubocop/cop/ignored_columns.rb b/rubocop/cop/ignored_columns.rb
index 14bcfa04ae1..4a6f1e4f2d9 100644
--- a/rubocop/cop/ignored_columns.rb
+++ b/rubocop/cop/ignored_columns.rb
@@ -2,18 +2,60 @@
 
 module RuboCop
   module Cop
-    # Cop that blacklists the usage of Group.public_or_visible_to_user
+    # Cop that blacklists the usage of `ActiveRecord::Base.ignored_columns=` directly
     class IgnoredColumns < RuboCop::Cop::Cop
-      MSG = 'Use `IgnoredColumns` concern instead of adding to `self.ignored_columns`.'
+      USE_CONCERN_MSG = 'Use `IgnoredColumns` concern instead of adding to `self.ignored_columns`.'
+      WRONG_MODEL_MSG = 'If the model exists in CE and EE, the column has to be ignored ' \
+        'in the CE model. If the model only exists in EE, then it has to be added there.'
 
       def_node_matcher :ignored_columns?, <<~PATTERN
         (send (self) :ignored_columns)
       PATTERN
 
+      def_node_matcher :ignore_columns?, <<~PATTERN
+        (send nil? :ignore_columns ...)
+      PATTERN
+
+      def_node_matcher :ignore_column?, <<~PATTERN
+        (send nil? :ignore_column ...)
+      PATTERN
+
       def on_send(node)
-        return unless ignored_columns?(node)
+        if ignored_columns?(node)
+          add_offense(node, location: :expression, message: USE_CONCERN_MSG)
+        end
+
+        if using_ignore?(node) && used_in_wrong_model?
+          add_offense(node, location: :expression, message: WRONG_MODEL_MSG)
+        end
+      end
+
+      private
+
+      def using_ignore?(node)
+        ignore_columns?(node) || ignore_column?(node)
+      end
+
+      def used_in_wrong_model?
+        file_path = processed_source.file_path
+
+        ee_model?(file_path) && ce_model_exists?(file_path)
+      end
+
+      def ee_model?(path)
+        path.include?(ee_directory)
+      end
+
+      def ee_directory
+        File.join(rails_root, 'ee')
+      end
+
+      def rails_root
+        File.expand_path('../..', __dir__)
+      end
 
-        add_offense(node, location: :expression)
+      def ce_model_exists?(path)
+        File.exist?(path.gsub(%r{/ee/}, '/'))
       end
     end
   end