[FieldDefinitions] Support heredoc descriptions

lib/rubocop-graphql.rb

@@ -8,6 +8,7 @@
 require_relative "rubocop/graphql/version"
 require_relative "rubocop/graphql/inject"
 require_relative "rubocop/graphql/description_method"
+require_relative "rubocop/graphql/heredoc"
 require_relative "rubocop/graphql/node_pattern"
 require_relative "rubocop/graphql/node_uniqueness"
 require_relative "rubocop/graphql/sorbet"

lib/rubocop/cop/graphql/field_definitions.rb

@@ -50,6 +50,7 @@ class FieldDefinitions < Base # rubocop:disable Metrics/ClassLength
         include RuboCop::GraphQL::NodePattern
         include RuboCop::Cop::RangeHelp
         include RuboCop::GraphQL::Sorbet
+        include RuboCop::GraphQL::Heredoc
 
         def_node_matcher :field_kwargs, <<~PATTERN
           (send nil? :field
@@ -188,7 +189,7 @@ def insert_new_resolver(corrector, field_definition, resolver_definition)
             "\n#{signature_to_insert(resolver_definition)}\n" \
               "#{indent(resolver_definition)}#{resolver_definition.source}\n"
 
-          field_definition_range = range_by_whole_lines(field_definition.loc.expression)
+          field_definition_range = range_including_heredoc(field_definition)
           corrector.insert_after(field_definition_range, source_to_insert)
         end
 

lib/rubocop/graphql/heredoc.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module GraphQL
+    module Heredoc
+      def heredoc?(node)
+        (node.str_type? || node.dstr_type?) && node.heredoc?
+      end
+
+      def range_including_heredoc(node)
+        field = RuboCop::GraphQL::Field.new(node)
+        last_heredoc = field.kwargs.instance_variable_get(:@nodes).reverse.find do |kwarg|
+                         heredoc?(kwarg.value)
+                       end&.value
+
+        range = node.loc.expression
+        range = range.join(last_heredoc.loc.heredoc_end) if last_heredoc
+
+        range_by_whole_lines(range)
+      end
+    end
+  end
+end

spec/rubocop/cop/graphql/field_definitions_spec.rb

@@ -323,6 +323,30 @@ def last_name
       end
     end
 
+    context "when field has a heredoc description" do
+      it "not registers an offense" do
+        expect_no_offenses(<<~RUBY)
+          class UserType < BaseType
+            field :first_name, String, null: true, description: <<~DESC
+              First Name.
+            DESC
+
+            def first_name
+              object.contact_data.first_name
+            end
+
+            field :last_name, String, null: true, description: <<~DESC
+              Last Name.
+            DESC
+
+            def last_name
+              object.contact_data.last_name
+            end
+          end
+        RUBY
+      end
+    end
+
     context "when class has single field" do
       it "not registers an offense" do
         expect_no_offenses(<<~RUBY)
@@ -454,6 +478,44 @@ def last_name
         RUBY
       end
 
+      it "registers offenses when field has a heredoc description" do
+        expect_offense(<<~RUBY)
+          class UserType < BaseType
+            field :first_name, String, null: true, description: <<~DESC
+            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Define resolver method after field definition.
+              First name.
+            DESC
+            field :last_name, String, null: true
+
+            def last_name
+              object.contact_data.last_name
+            end
+
+            def first_name
+              object.contact_data.first_name
+            end
+          end
+        RUBY
+
+        expect_correction(<<~RUBY)
+          class UserType < BaseType
+            field :first_name, String, null: true, description: <<~DESC
+              First name.
+            DESC
+
+            def first_name
+              object.contact_data.first_name
+            end
+
+            field :last_name, String, null: true
+
+            def last_name
+              object.contact_data.last_name
+            end
+          end
+        RUBY
+      end
+
       it "registers offenses when type classes are nested within a module" do
         expect_offense(<<~RUBY)
           module Types