1 files changed, 44 insertions, 0 deletions
diff --git a/rubocop/cop/graphql/old_types.rb b/rubocop/cop/graphql/old_types.rb
new file mode 100644
index 00000000000..2df594c7016
--- /dev/null
+++ b/rubocop/cop/graphql/old_types.rb
@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+# This cop checks for use of older GraphQL  types in GraphQL fields
+# and arguments.
+# GraphQL::ID_TYPE, GraphQL::INT_TYPE, GraphQL::STRING_TYPE, GraphQL::BOOLEAN_TYPE
+#
+# @example
+#
+#   # bad
+#   class AwfulClass
+#     field :some_field, GraphQL::STRING_TYPE
+#   end
+#
+#   # good
+#   class GreatClass
+#     field :some_field, GraphQL::Types::String
+#   end
+
+module RuboCop
+  module Cop
+    module Graphql
+      class OldTypes < RuboCop::Cop::Cop
+        MSG_ID      = 'Avoid using GraphQL::ID_TYPE. Use GraphQL::Types::ID instead'
+        MSG_INT     = 'Avoid using GraphQL::INT_TYPE. Use GraphQL::Types::Int instead'
+        MSG_STRING  = 'Avoid using GraphQL::STRING_TYPE. Use GraphQL::Types::String instead'
+        MSG_BOOLEAN = 'Avoid using GraphQL::BOOLEAN_TYPE. Use GraphQL::Types::Boolean instead'
+
+        def_node_matcher :has_old_type?, <<~PATTERN
+          (send nil? {:field :argument}
+            (sym _)
+            (const (const nil? :GraphQL) ${:ID_TYPE :INT_TYPE :STRING_TYPE :BOOLEAN_TYPE})
+            (...)?)
+        PATTERN
+
+        def on_send(node)
+          old_constant = has_old_type?(node)
+          return unless old_constant
+
+          add_offense(node, location: :expression, message: "#{self.class}::MSG_#{old_constant[0..-6]}".constantize)
+        end
+      end
+    end
+  end
+end