Support ruby 2.2

Author: rmosolgo

.rubocop.yml

@@ -3,7 +3,7 @@ require:
 
 AllCops:
   DisabledByDefault: true
-  TargetRubyVersion: 2.3
+  TargetRubyVersion: 2.2
   Exclude:
     - 'lib/graphql/language/lexer.rb'
     - 'lib/graphql/language/parser.rb'

guides/_plugins/api_doc.rb

@@ -22,7 +22,7 @@ def api_doc(input)
 
     def link_to_img(img_path, img_title)
       full_img_path = "#{@context.registers[:site].baseurl}#{img_path}"
-      <<~HTML
+      <<-HTML
         <a href="#{full_img_path}" target="_blank" class="img-link">
           <img src="#{full_img_path}" title="#{img_title}" alt="#{img_title}" />
         </a>
@@ -74,7 +74,7 @@ def initialize(tag_name, guide_info, tokens)
     end
 
     def render(context)
-      <<~HTML.chomp
+      <<-HTML.chomp
       <a href="#{context["site"]["baseurl"]}/#{@path}">#{@text}</a>
       HTML
     end

lib/graphql/static_validation/base_visitor.rb

@@ -146,11 +146,14 @@ def on_fragment_spread(node, parent)
         end
 
         def on_input_object(node, parent)
-          is_list = @argument_definitions.last&.type&.list? == true
-
-          @path.push(parent.children.index(node)) if is_list
-          super
-          @path.pop if is_list
+          arg_defn = @argument_definitions.last
+          if arg_defn && arg_defn.type.list?
+            @path.push(parent.children.index(node))
+            super
+            @path.pop
+          else
+            super
+          end
         end
 
         # @return [GraphQL::BaseType] The current object type

spec/graphql/execution/lookahead_spec.rb

@@ -356,7 +356,7 @@ def query(doc = document)
     end
 
     it "avoids merging selections for same field name on distinct types" do
-      query = GraphQL::Query.new(LookaheadTest::Schema, <<~GRAPHQL)
+      query = GraphQL::Query.new(LookaheadTest::Schema, <<-GRAPHQL)
         query {
           node(id: "Cardinal") {
             ... on BirdSpecies {