1 files changed, 0 insertions, 12 deletions
diff --git a/test/ruby/test_io_m17n.rb b/test/ruby/test_io_m17n.rb
index b86dfb3274..4f01a82674 100644
--- a/test/ruby/test_io_m17n.rb
+++ b/test/ruby/test_io_m17n.rb
@@ -1,7 +1,6 @@
 require 'test/unit'
 require 'tmpdir'
 require 'timeout'
-require 'stringio'
 require_relative 'envutil'
 
 class TestIO_M17N < Test::Unit::TestCase
@@ -12,17 +11,6 @@ class TestIO_M17N < Test::Unit::TestCase
     Encoding::UTF_8
   ]
 
-  def assert_warning(pat, mesg=nil)
-    begin
-      org_stderr = $stderr
-      $stderr = StringIO.new(warn = '')
-      yield
-    ensure
-      $stderr = org_stderr
-    end
-    assert_match(pat, warn, mesg)
-  end
-
   def with_tmpdir
     Dir.mktmpdir {|dir|
       Dir.chdir(dir) {