Add test about no warnings emitting at lazy initialization of an instance variable

Author: andrykonchin

spec/ruby/language/variables_spec.rb

@@ -842,5 +842,12 @@ def obj.foobar; a = @a; end
         -> { obj.foobar }.should_not complain(verbose: true)
       end
     end
+
+    it "doesn't warn at lazy initialization" do
+      obj = Object.new
+      def obj.foobar; @a ||= 42; end
+
+      -> { obj.foobar }.should_not complain(verbose: true)
+    end
   end
 end