merges r24509 from trunk into ruby_1_9_1.

--
* string.c (rb_str_new_frozen): must not change encoding of frozen
  shared string.  [ruby-dev:39068]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_1@25477 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 13 insertions, 0 deletions

diff --git a/test/ruby/test_string.rb b/test/ruby/test_string.rb
index bf0ed6a830..7e9176e507 100644
--- a/test/ruby/test_string.rb
+++ b/test/ruby/test_string.rb
@@ -1786,4 +1786,17 @@ class TestString < Test::Unit::TestCase
       ("aaaaaaaa".."zzzzzzzz").each {|s| s.to_sym }
     INPUT
   end
+
+  def test_shared_force_encoding
+    s = "\u{3066}\u{3059}\u{3068}".gsub(//, '')
+    h = {}
+    h[s] = nil
+    k = h.keys[0]
+    assert_equal(s, k, '[ruby-dev:39068]')
+    assert_equal(Encoding::UTF_8, k.encoding, '[ruby-dev:39068]')
+    s.dup.force_encoding(Encoding::ASCII_8BIT).gsub(//, '')
+    k = h.keys[0]
+    assert_equal(s, k, '[ruby-dev:39068]')
+    assert_equal(Encoding::UTF_8, k.encoding, '[ruby-dev:39068]')
+  end
 end