5 files changed, 12 insertions, 17 deletions
diff --git a/test/ruby/test_dir_m17n.rb b/test/ruby/test_dir_m17n.rb
index 4063c834de..bb60b0af76 100644
--- a/test/ruby/test_dir_m17n.rb
+++ b/test/ruby/test_dir_m17n.rb
@@ -208,7 +208,7 @@ class TestDir_M17N < Test::Unit::TestCase
           when /darwin/
             filename = filename.encode("utf-8", "euc-jp").b
           when /mswin|mingw/
-            if ents.include?(win_expected_filename.dup.force_encoding("ASCII-8BIT"))
+            if ents.include?(win_expected_filename.b)
               ents = Dir.entries(".", {:encoding => Encoding.find("filesystem")})
               filename = win_expected_filename
             end
diff --git a/test/ruby/test_econv.rb b/test/ruby/test_econv.rb
index f423ebfc9e..073355f319 100644
--- a/test/ruby/test_econv.rb
+++ b/test/ruby/test_econv.rb
@@ -3,12 +3,8 @@ require 'test/unit'
 class TestEncodingConverter < Test::Unit::TestCase
   def check_ec(edst, esrc, eres, dst, src, ec, off, len, opts=nil)
     res = ec.primitive_convert(src, dst, off, len, opts)
-    assert_equal([edst.dup.force_encoding("ASCII-8BIT"),
-                  esrc.dup.force_encoding("ASCII-8BIT"),
-                  eres],
-                 [dst.dup.force_encoding("ASCII-8BIT"),
-                  src.dup.force_encoding("ASCII-8BIT"),
-                  res])
+    assert_equal([edst.b, esrc.b, eres],
+                 [dst.b,  src.b,  res])
   end
 
   def assert_econv(converted, eres, obuf_bytesize, ec, consumed, rest, opts=nil)
@@ -22,8 +18,8 @@ class TestEncodingConverter < Test::Unit::TestCase
 
   def assert_errinfo(e_res, e_enc1, e_enc2, e_error_bytes, e_readagain_bytes, ec)
     assert_equal([e_res, e_enc1, e_enc2,
-                  e_error_bytes && e_error_bytes.dup.force_encoding("ASCII-8BIT"),
-                  e_readagain_bytes && e_readagain_bytes.dup.force_encoding("ASCII-8BIT")],
+                  e_error_bytes && e_error_bytes.b,
+                  e_readagain_bytes && e_readagain_bytes.b],
                  ec.primitive_errinfo)
   end
 
diff --git a/test/ruby/test_io_m17n.rb b/test/ruby/test_io_m17n.rb
index a91fccee5f..ed8ac99946 100644
--- a/test/ruby/test_io_m17n.rb
+++ b/test/ruby/test_io_m17n.rb
@@ -1711,8 +1711,7 @@ EOT
         args.each {|arg| f.print arg }
       }
       content = File.read("t", :mode=>"rb:ascii-8bit")
-      assert_equal(expected.dup.force_encoding("ascii-8bit"),
-                   content.force_encoding("ascii-8bit"))
+      assert_equal(expected.b, content.b)
     }
   end
 
@@ -1892,7 +1891,7 @@ EOT
     with_tmpdir {
       src = "\u3042\r\n"
       generate_file("t.txt", src)
-      srcbin = src.dup.force_encoding("ascii-8bit")
+      srcbin = src.b
       open("t.txt", "rt:utf-8:euc-jp") {|f|
         f.binmode
         result = f.read
diff --git a/test/ruby/test_m17n.rb b/test/ruby/test_m17n.rb
index 4efe18187b..a9cb86a5c8 100644
--- a/test/ruby/test_m17n.rb
+++ b/test/ruby/test_m17n.rb
@@ -8,7 +8,7 @@ class TestM17N < Test::Unit::TestCase
 
   module AESU
     def ua(str) str.dup.force_encoding("US-ASCII") end
-    def a(str) str.dup.force_encoding("ASCII-8BIT") end
+    def a(str) str.b end
     def e(str) str.dup.force_encoding("EUC-JP") end
     def s(str) str.dup.force_encoding("Windows-31J") end
     def u(str) str.dup.force_encoding("UTF-8") end
@@ -1130,7 +1130,7 @@ class TestM17N < Test::Unit::TestCase
 
   def test_dup_scan
     s1 = e("\xa4\xa2")*100
-    s2 = s1.dup.force_encoding("ascii-8bit")
+    s2 = s1.b
     s2.scan(/\A./n) {|f|
       assert_equal(Encoding::ASCII_8BIT, f.encoding)
     }
@@ -1138,7 +1138,7 @@ class TestM17N < Test::Unit::TestCase
 
   def test_dup_aref
     s1 = e("\xa4\xa2")*100
-    s2 = s1.dup.force_encoding("ascii-8bit")
+    s2 = s1.b
     assert_equal(Encoding::ASCII_8BIT, s2[10..-1].encoding)
   end
 
diff --git a/test/ruby/test_m17n_comb.rb b/test/ruby/test_m17n_comb.rb
index 83c3f8aa95..cf00e52157 100644
--- a/test/ruby/test_m17n_comb.rb
+++ b/test/ruby/test_m17n_comb.rb
@@ -1575,8 +1575,8 @@ class TestM17NComb < Test::Unit::TestCase
         assert_raise(Encoding::CompatibilityError, desc) { s1.start_with?(s2) }
         next
       end
-      s1 = s1.dup.force_encoding("ASCII-8BIT")
-      s2 = s2.dup.force_encoding("ASCII-8BIT")
+      s1 = s1.b
+      s2 = s2.b
       if s1.length < s2.length
         assert_equal(false, enccall(s1, :start_with?, s2), desc)
         next