test_autoload.rb: use class_eval

* test/ruby/test_autoload.rb (add_autoload): use class_eval
  instead of string eval.

* test/ruby/test_autoload.rb (remove_autoload_constant): ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@50529 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/ruby/test_autoload.rb

@@ -214,19 +214,11 @@ p Foo::Bar
 
   def add_autoload(path)
     (@autoload_paths ||= []) << path
-    eval <<-END
-      class ::Object
-        autoload :AutoloadTest, #{path.dump}
-      end
-    END
+    ::Object.class_eval {autoload(:AutoloadTest, path)}
   end
 
   def remove_autoload_constant
     $".replace($" - @autoload_paths)
-    eval <<-END
-      class ::Object
-        remove_const(:AutoloadTest)
-      end
-    END
+    ::Object.class_eval {remove_const(:AutoloadTest)}
   end
 end