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

4 files changed, 23 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index fc257e2add..9c3b100930 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed Aug 12 12:59:51 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* string.c (rb_str_new_frozen): must not change encoding of frozen
+	  shared string.  [ruby-dev:39068]
+
 Fri Oct 23 10:51:04 2009  Yuki Sonoda (Yugui)  <yugui@yugui.jp>
 
 	* test/ruby/test_m17n.rb (TestM17N#test_sprintf_s):
diff --git a/string.c b/string.c
index 2017d1023b..ba40ddd7dc 100644
--- a/string.c
+++ b/string.c
@@ -666,13 +666,14 @@ rb_str_new_frozen(VALUE orig)
 	long ofs;
 	ofs = RSTRING_LEN(str) - RSTRING_LEN(orig);
 	if ((ofs > 0) || (klass != RBASIC(str)->klass) ||
-	    (!OBJ_TAINTED(str) && OBJ_TAINTED(orig))) {
+	    (!OBJ_TAINTED(str) && OBJ_TAINTED(orig)) ||
+	    ENCODING_GET(str) != ENCODING_GET(orig)) {
 	    str = str_new3(klass, str);
 	    RSTRING(str)->as.heap.ptr += ofs;
 	    RSTRING(str)->as.heap.len -= ofs;
+	    rb_enc_cr_str_exact_copy(str, orig);
+	    OBJ_INFECT(str, orig);
 	}
-	rb_enc_cr_str_exact_copy(str, orig);
-	OBJ_INFECT(str, orig);
     }
     else if (STR_EMBED_P(orig)) {
 	str = str_new(klass, RSTRING_PTR(orig), RSTRING_LEN(orig));
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
diff --git a/version.h b/version.h
index 13693313dd..84ea39245e 100644
--- a/version.h
+++ b/version.h
@@ -1,5 +1,5 @@
 #define RUBY_VERSION "1.9.1"
-#define RUBY_PATCHLEVEL 285
+#define RUBY_PATCHLEVEL 286
 #define RUBY_VERSION_MAJOR 1
 #define RUBY_VERSION_MINOR 9
 #define RUBY_VERSION_TEENY 1