1 files changed, 39 insertions, 0 deletions
diff --git a/rubocop/cop/code_reuse/finder.rb b/rubocop/cop/code_reuse/finder.rb
new file mode 100644
index 00000000000..1d70befe79b
--- /dev/null
+++ b/rubocop/cop/code_reuse/finder.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+require_relative '../../code_reuse_helpers'
+
+module RuboCop
+  module Cop
+    module CodeReuse
+      # Cop that enforces various code reuse rules for Finders.
+      class Finder < RuboCop::Cop::Cop
+        include CodeReuseHelpers
+
+        IN_FINDER = 'Finders can not be used inside a Finder.'
+
+        IN_MODEL_CLASS_METHOD =
+          'Finders can not be used inside model class methods.'
+
+        SUFFIX = 'Finder'
+
+        def on_class(node)
+          if in_finder?(node)
+            check_finder(node)
+          elsif in_model?(node)
+            check_model_class_methods(node)
+          end
+        end
+
+        def check_finder(node)
+          disallow_send_to(node, SUFFIX, IN_FINDER)
+        end
+
+        def check_model_class_methods(node)
+          each_class_method(node) do |def_node|
+            disallow_send_to(def_node, SUFFIX, IN_MODEL_CLASS_METHOD)
+          end
+        end
+      end
+    end
+  end
+end