merge revision(s) 46896-46898: [Backport #10078]

	* string.c (rb_str_count): fix wrong single-byte optimization.
	  7bit ascii can be a trailing byte in Shift_JIS.
	  [ruby-dev:48442] [Bug #10078]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@47401 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 20 insertions, 9 deletions

diff --git a/string.c b/string.c
index d6a5232411..81e78576ad 100644
--- a/string.c
+++ b/string.c
@@ -5794,21 +5794,25 @@ rb_str_count(int argc, VALUE *argv, VALUE str)
 {
     char table[TR_TABLE_SIZE];
     rb_encoding *enc = 0;
-    VALUE del = 0, nodel = 0;
+    VALUE del = 0, nodel = 0, tstr;
     char *s, *send;
     int i;
     int ascompat;
 
     rb_check_arity(argc, 1, UNLIMITED_ARGUMENTS);
-    for (i=0; i<argc; i++) {
-	VALUE tstr = argv[i];
-	unsigned char c;
 
-	StringValue(tstr);
-	enc = rb_enc_check(str, tstr);
-	if (argc == 1 && RSTRING_LEN(tstr) == 1 && rb_enc_asciicompat(enc) &&
-	    (c = RSTRING_PTR(tstr)[0]) < 0x80 && !is_broken_string(str)) {
+    tstr = argv[0];
+    StringValue(tstr);
+    enc = rb_enc_check(str, tstr);
+    if (argc == 1) {
+	const char *ptstr;
+	if (RSTRING_LEN(tstr) == 1 && rb_enc_asciicompat(enc) &&
+	    (ptstr = RSTRING_PTR(tstr),
+	     ONIGENC_IS_ALLOWED_REVERSE_MATCH(enc, (const unsigned char *)ptstr, (const unsigned char *)ptstr+1)) &&
+	    !is_broken_string(str)) {
 	    int n = 0;
+	    int clen;
+	    unsigned char c = rb_enc_codepoint_len(ptstr, ptstr+1, &clen, enc);
 
 	    s = RSTRING_PTR(str);
 	    if (!s || RSTRING_LEN(str) == 0) return INT2FIX(0);
@@ -5818,7 +5822,14 @@ rb_str_count(int argc, VALUE *argv, VALUE str)
 	    }
 	    return INT2NUM(n);
 	}
-	tr_setup_table(tstr, table, i==0, &del, &nodel, enc);
+    }
+
+    tr_setup_table(tstr, table, TRUE, &del, &nodel, enc);
+    for (i=1; i<argc; i++) {
+	tstr = argv[i];
+	StringValue(tstr);
+	enc = rb_enc_check(str, tstr);
+	tr_setup_table(tstr, table, FALSE, &del, &nodel, enc);
     }
 
     s = RSTRING_PTR(str);