NASHORN-759.js revision 877:cf4d2252d444 
1/*
2 * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24/*
25 * NASHORN-759 - Efficient string concatenation with + operator
26 *
27 * @test
28 * @run
29 */
30
31// Check invalidation of callsite for non-string CharSequence
32function checkProps(s) {
33    print(typeof s);
34    print(typeof s.length);
35    print(s.charCodeAt === String.prototype.charCodeAt);
36    print();
37}
38
39var s1 = "foo";
40var s2 = "bar";
41var s3 = s1 + s2 + s1 + s2;
42var s4 = new java.lang.StringBuilder("abc");
43checkProps(s1);
44checkProps(s2);
45checkProps(s3);
46checkProps(s4);
47
48// Rebuild string and compare to original
49function rebuildString(s) {
50    var buf = s.split("");
51    print(buf);
52    while (buf.length > 1) {
53        var result = [];
54        buf.reduce(function(previous, current, index) {
55            if (previous) {
56                result.push(previous + current);
57                return null;
58            } else if (index === buf.length - 1) {
59                result.push(current);
60                return null;
61            } else {
62                return current;
63            }
64        });
65        buf = result;
66        print(buf);
67    }
68    return buf[0];
69}
70
71var n1 = "The quick gray nashorn jumps over the lazy zebra.";
72var n2 = rebuildString(n1);
73print(n1, n2, n2.length, n1 == n2, n1 === n2, n1 < n2, n1 <= n2, n1 > n2, n1 >= n2);
74checkProps(n2);
75
76var n3 = rebuildString(rebuildString(n2));
77print(n3, n3.length, n1 == n3, n2 == n3, n1 === n3, n2 === n3);
78checkProps(n3);
79