[Fix rubocop#300] Fix Rails/RenderInline error on variable key in r…

…ender options

Closes: rubocop#300

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Bug fixes
 
 * [#297](https://github.com/rubocop-hq/rubocop-rails/pull/297): Handle an upstream Ruby issue where the DidYouMean module is not available, which would break the `Rails/UnknownEnv` cop. ([@taylorthurlow][])
+* [#300](https://github.com/rubocop-hq/rubocop-rails/issues/300): Fix `Rails/RenderInline` error on variable key in render options. ([@tejasbubane][])
 
 ### Changes
 

lib/rubocop/cop/rails/render_inline.rb

@@ -27,21 +27,15 @@ module Rails
       class RenderInline < Cop
         MSG = 'Prefer using a template over inline rendering.'
 
-        def_node_matcher :render_with_options?, <<~PATTERN
-          (send nil? :render $(hash ...))
+        def_node_matcher :render_with_inline_option?, <<~PATTERN
+          (send nil? :render (hash <(pair {(sym :inline) (str "inline")} _) ...>))
         PATTERN
 
         def on_send(node)
-          render_with_options?(node) do |options|
-            add_offense(node) if includes_inline_key?(options)
+          render_with_inline_option?(node) do
+            add_offense(node)
           end
         end
-
-        private
-
-        def includes_inline_key?(node)
-          node.keys.find { |key| key.value.to_sym == :inline }
-        end
       end
     end
   end

spec/rubocop/cop/rails/render_inline_spec.rb

@@ -22,4 +22,17 @@
       render :index
     RUBY
   end
+
+  it 'does not register an offense when passing other options to render' do
+    expect_no_offenses(<<~RUBY)
+      render json: users, serializer: UserSerializer
+    RUBY
+  end
+
+  it 'does not register an offense when passing other options where key is a variable' do
+    expect_no_offenses(<<~RUBY)
+      serializer = users.respond_to?(:each) ? :each_serializer : :serializer
+      render json: users, serializer => UserSerializer
+    RUBY
+  end
 end