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// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Flags: --allow-natives-syntax
function get_thin_string(a, b) {
var str = a + b; // Make a ConsString.
var o = {};
o[str]; // Turn it into a ThinString.
return str;
}
var str = get_thin_string("foo", "bar");
var re = /.o+ba./;
assertEquals(["foobar"], re.exec(str));
assertEquals(["foobar"], re.exec(str));
assertEquals(["foobar"], re.exec(str));
function CheckCS() {
assertEquals("o", str.substring(1, 2));
assertEquals("f".charCodeAt(0), str.charCodeAt(0));
assertEquals("f", str.split(/oo/)[0]);
}
CheckCS();
%OptimizeFunctionOnNextCall(CheckCS);
CheckCS();
function CheckTF() {
try {} catch(e) {} // Turbofan.
assertEquals("o", str.substring(1, 2));
assertEquals("f".charCodeAt(0), str.charCodeAt(0));
assertEquals("f", str.split(/oo/)[0]);
}
CheckTF();
%OptimizeFunctionOnNextCall(CheckTF);
CheckTF();
// Flat cons strings can point to a thin string.
function get_cons_thin_string(a, b) {
// Make a ConsString.
var s = a + b;
// Flatten it.
s.endsWith("a");
// Internalize the first part.
var o = {};
o[s];
return s;
}
var s = get_cons_thin_string("__________", "@@@@@@@@@@a");
s.match(/.*a/);
assertEquals("________", s.substring(0, 8));
function cc1(s) {
assertEquals(95, s.charCodeAt(0));
assertEquals(95, s.codePointAt(0));
}
cc1(s);
cc1(s);
%OptimizeFunctionOnNextCall(cc1);
cc1(s);
// Sliced strings can have a thin string as their parent.
function get_sliced_thin_string(a, b) {
// Make a long thin string.
var s = a + b;
// Slice a substring out of it.
var slice = s.substring(0, 20);
// Make the original string thin.
var o = {};
o[s];
return slice;
}
var t = get_sliced_thin_string("abcdefghijklmnopqrstuvwxyz",
"abcdefghijklmnopqrstuvwxyz");
assertEquals("abcdefghijklmnopqrst", decodeURI(t));
function cc2(s) {
assertEquals(97, s.charCodeAt(0));
assertEquals(97, s.codePointAt(0));
}
cc2(t);
cc2(t);
%OptimizeFunctionOnNextCall(cc2);
cc2(t);
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