test_fileutils.rb: test :preserve option

* test/fileutils/test_fileutils.rb (test_cp_preserve_permissions):
  should test with setting :preserve option.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45600 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/fileutils/test_fileutils.rb

@@ -272,7 +272,7 @@ class TestFileUtils < Test::Unit::TestCase
     bug4507 = '[ruby-core:35518]'
     touch 'tmp/cptmp'
     chmod 0755, 'tmp/cptmp'
-    cp 'tmp/cptmp', 'tmp/cptmp2'
+    cp 'tmp/cptmp', 'tmp/cptmp2', :preserve => true
     assert_equal_filemode('tmp/cptmp', 'tmp/cptmp2', bug4507)
   end