fix string range to have full unicode range (up to 10FFFF).

add test for string range.

test has minor failure: after loop the index == len(s); should be len(s)-1
in this case.  according to spec, vars are left at position at last
iteration.

R=ken,rsc
DELTA=259  (161 added, 96 deleted, 2 changed)
OCL=27343
CL=27343

test/stringrange.go

@@ -0,0 +1,47 @@
+// $G $F.go && $L $F.$A && ./$A.out
+
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import(
+        "fmt";
+        "utf8";
+)
+
+func main() {
+	s := "\000\123\x00\xca\xFE\u0123\ubabe\U0000babe\U0010FFFFx";
+	expect := []int{ 0, 0123, 0, 0xFFFD, 0xFFFD, 0x123, 0xbabe, 0xbabe, 0x10FFFF, 'x' };
+	var rune, size int;
+	offset := 0;
+	var i, c int;
+	ok := true;
+	cnum := 0;
+	for i, c = range s {
+		rune, size := utf8.DecodeRuneInString(s, i);  // check it another way
+		if i != offset {
+			fmt.Printf("unexpected offset %d not %d\n", i, offset);
+			ok = false;
+		}
+		if rune != expect[cnum] {
+			fmt.Printf("unexpected rune %d from DecodeRuneInString: %x not %x\n", i, rune, expect[cnum]);
+			ok = false;
+		}
+		if c != expect[cnum] {
+			fmt.Printf("unexpected rune %d from range: %x not %x\n", i, rune, expect[cnum]);
+			ok = false;
+		}
+		offset += size;
+		cnum++;
+	}
+	if i != len(s)-1 {
+		fmt.Println("after loop i is", i, "not", len(s)-1);
+		ok = false;
+	}
+	if !ok {
+		fmt.Println("FAIL");
+		sys.Exit(1)
+	}
+}