merge revision(s) 51344: [Backport ruby#11387]

	* string.c (rb_str_reverse): reversed string is not a substring,
	  and should not set coderange of the original string.
	  [ruby-dev:49189] [Bug ruby#11387]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_1@51600 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

Author: unak

ChangeLog

@@ -1,3 +1,9 @@
+Mon Aug 17 16:44:01 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* string.c (rb_str_reverse): reversed string is not a substring,
+	  and should not set coderange of the original string.
+	  [ruby-dev:49189] [Bug #11387]
+
 Mon Aug 17 16:24:10 2015  Tanaka Akira  <akr@fsij.org>
 
 	* lib/time.rb (strptime): Support %s.%N.

string.c

@@ -4544,35 +4544,37 @@ rb_str_reverse(VALUE str)
     rb_encoding *enc;
     VALUE rev;
     char *s, *e, *p;
-    int single = 1;
+    int cr;
 
     if (RSTRING_LEN(str) <= 1) return rb_str_dup(str);
     enc = STR_ENC_GET(str);
     rev = rb_str_new5(str, 0, RSTRING_LEN(str));
     s = RSTRING_PTR(str); e = RSTRING_END(str);
     p = RSTRING_END(rev);
+    cr = ENC_CODERANGE(str);
 
     if (RSTRING_LEN(str) > 1) {
 	if (single_byte_optimizable(str)) {
 	    while (s < e) {
 		*--p = *s++;
 	    }
 	}
-	else if (ENC_CODERANGE(str) == ENC_CODERANGE_VALID) {
+	else if (cr == ENC_CODERANGE_VALID) {
 	    while (s < e) {
 		int clen = rb_enc_fast_mbclen(s, e, enc);
 
-		if (clen > 1 || (*s & 0x80)) single = 0;
 		p -= clen;
 		memcpy(p, s, clen);
 		s += clen;
 	    }
 	}
 	else {
+	    cr = rb_enc_asciicompat(enc) ?
+		ENC_CODERANGE_7BIT : ENC_CODERANGE_VALID;
 	    while (s < e) {
 		int clen = rb_enc_mbclen(s, e, enc);
 
-		if (clen > 1 || (*s & 0x80)) single = 0;
+		if (clen > 1 || (*s & 0x80)) cr = ENC_CODERANGE_UNKNOWN;
 		p -= clen;
 		memcpy(p, s, clen);
 		s += clen;
@@ -4581,15 +4583,8 @@ rb_str_reverse(VALUE str)
     }
     STR_SET_LEN(rev, RSTRING_LEN(str));
     OBJ_INFECT(rev, str);
-    if (ENC_CODERANGE(str) == ENC_CODERANGE_UNKNOWN) {
-	if (single) {
-	    ENC_CODERANGE_SET(str, ENC_CODERANGE_7BIT);
-	}
-	else {
-	    ENC_CODERANGE_SET(str, ENC_CODERANGE_VALID);
-	}
-    }
-    rb_enc_cr_str_copy_for_substr(rev, str);
+    str_enc_copy(rev, str);
+    ENC_CODERANGE_SET(rev, cr);
 
     return rev;
 }

test/ruby/test_m17n.rb

@@ -1132,7 +1132,12 @@ def test_casecmp
   end
 
   def test_reverse
-    assert_equal(u("\xf0jihgfedcba"), u("abcdefghij\xf0").reverse)
+    bug11387 = '[ruby-dev:49189] [Bug #11387]'
+    s1 = u("abcdefghij\xf0")
+    s2 = s1.reverse
+    assert_not_predicate(s1, :valid_encoding?, bug11387)
+    assert_equal(u("\xf0jihgfedcba"), s2)
+    assert_not_predicate(s2, :valid_encoding?, bug11387)
   end
 
   def test_reverse_bang

version.h

@@ -1,6 +1,6 @@
 #define RUBY_VERSION "2.1.7"
 #define RUBY_RELEASE_DATE "2015-08-17"
-#define RUBY_PATCHLEVEL 383
+#define RUBY_PATCHLEVEL 384
 
 #define RUBY_RELEASE_YEAR 2015
 #define RUBY_RELEASE_MONTH 8