From 6e0b5f40cc708f93013262c55991a6ab4e115823 Mon Sep 17 00:00:00 2001
From: nobu <nobu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Tue, 8 Jul 2008 16:38:40 +0000
Subject: [PATCH] * string.c (rb_str_succ): alphabets or numerics mutually
 enclosing   non-alphanumeric characters can carry up.  e.g., "1.999".succ
 should   be "2.000".

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@17963 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog                |  6 ++++++
 string.c                 | 25 +++++++++++++++++--------
 test/ruby/test_string.rb |  1 +
 3 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 0320aced2c..baef55cb0f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Wed Jul  9 01:38:37 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* string.c (rb_str_succ): alphabets or numerics mutually enclosing
+	  non-alphanumeric characters can carry up.  e.g., "1.999".succ should
+	  be "2.000".
+
 Wed Jul  9 00:12:31 2008  Yusuke Endoh  <mame@tsg.ne.jp>
 
 	* thread.c (rb_set_coverages, rb_reset_coverages): enable and disable
diff --git a/string.c b/string.c
index 8c1cf0d831..e1bb65599e 100644
--- a/string.c
+++ b/string.c
@@ -2516,11 +2516,12 @@ rb_str_succ(VALUE orig)
 {
     rb_encoding *enc;
     VALUE str;
-    char *sbeg, *s, *e;
+    char *sbeg, *s, *e, *last_alnum = 0;
     int c = -1;
     long l;
     char carry[ONIGENC_CODE_TO_MBC_MAXLEN] = "\1";
     int carry_pos = 0, carry_len = 1;
+    enum neighbor_char neighbor = NEIGHBOR_FOUND;
 
     str = rb_str_new5(orig, RSTRING_PTR(orig), RSTRING_LEN(orig));
     rb_enc_cr_str_copy_for_substr(str, orig);
@@ -2532,19 +2533,27 @@ rb_str_succ(VALUE orig)
     s = e = sbeg + RSTRING_LEN(str);
 
     while ((s = rb_enc_prev_char(sbeg, s, enc)) != 0) {
-        enum neighbor_char neighbor;
+	if (neighbor == NEIGHBOR_NOT_CHAR && last_alnum) {
+	    if (ISALPHA(*last_alnum) ? ISDIGIT(*s) :
+		ISDIGIT(*last_alnum) ? ISALPHA(*s) : 0) {
+		s = last_alnum;
+		break;
+	    }
+	}
 	if ((l = rb_enc_precise_mbclen(s, e, enc)) <= 0) continue;
         neighbor = enc_succ_alnum_char(s, l, enc, carry);
-        if (neighbor == NEIGHBOR_NOT_CHAR) {
-	    if (c == -1) continue;
-            s++;
+        switch (neighbor) {
+	  case NEIGHBOR_NOT_CHAR:
+	    continue;
+	  case NEIGHBOR_FOUND:
+	    return str;
+	  case NEIGHBOR_WRAPPED:
+	    last_alnum = s;
+	    break;
 	}
-        else if (neighbor == NEIGHBOR_FOUND)
-            return str;
         c = 1;
         carry_pos = s - sbeg;
         carry_len = l;
-        if (neighbor == NEIGHBOR_NOT_CHAR) break;
     }
     if (c == -1) {		/* str contains no alnum */
 	s = e;
diff --git a/test/ruby/test_string.rb b/test/ruby/test_string.rb
index 29bc2672ec..37278b192a 100644
--- a/test/ruby/test_string.rb
+++ b/test/ruby/test_string.rb
@@ -1221,6 +1221,7 @@ class TestString < Test::Unit::TestCase
 
     assert_equal(S("124"),  S("123").succ)
     assert_equal(S("1000"), S("999").succ)
+    assert_equal(S("2.000"), S("1.999").succ)
 
     assert_equal(S("No.10"), S("No.9").succ)
     assert_equal(S("2000aaa"),  S("1999zzz").succ)