Merge bleeding edge up to 9192 into the GC branch.

test/mjsunit/string-slices.js

 // Copyright 2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
 //       with the distribution.
 //     * Neither the name of Google Inc. nor the names of its
 //       contributors may be used to endorse or promote products derived
 //       from this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+// Flags: --string-slices --expose-externalize-string
+
 var s = 'abcdefghijklmn';
 assertEquals(s, s.substr());
 assertEquals(s, s.substr(0));
 assertEquals(s, s.substr('0'));
 assertEquals(s, s.substr(void 0));
 assertEquals(s, s.substr(null));
 assertEquals(s, s.substr(false));
 assertEquals(s, s.substr(0.9));
 assertEquals(s, s.substr({ valueOf: function() { return 0; } }));
 assertEquals(s, s.substr({ toString: function() { return '0'; } }));
@@ skipping 10 matching lines @@
 assertEquals(s.substring(s.length - 1), s.substr(-1));
 assertEquals(s.substring(s.length - 1), s.substr(-1.2));
 assertEquals(s.substring(s.length - 1), s.substr(-1.7));
 assertEquals(s.substring(s.length - 2), s.substr(-2));
 assertEquals(s.substring(s.length - 2), s.substr(-2.3));
 assertEquals(s.substring(s.length - 2, s.length - 1), s.substr(-2, 1));
 assertEquals(s, s.substr(-100));
 assertEquals('abc', s.substr(-100, 3));
 assertEquals(s1, s.substr(-s.length + 1));
 
-// assertEquals('', s.substr(0, void 0)); // smjs and rhino 
+// assertEquals('', s.substr(0, void 0)); // smjs and rhino
 assertEquals('abcdefghijklmn', s.substr(0, void 0));  // kjs and v8
 assertEquals('', s.substr(0, null));
 assertEquals(s, s.substr(0, String(s.length)));
 assertEquals('a', s.substr(0, true));
 
 
 // Test substrings of different lengths and alignments.
 // First ASCII.
 var x = "ASCII";
 for (var i = 0; i < 25; i++) {
   x += (i >> 4).toString(16) + (i & 0x0f).toString(16);
 }
 /x/.exec(x);  // Try to force a flatten.
 for (var i = 5; i < 25; i++) {
   for (var j = 0; j < 25; j++) {
     var z = x.substring(i, i+j);
     var w = Math.random() * 42;  // Allocate something new in new-space.
     assertEquals(j, z.length);
     for (var k = 0; k < j; k++) {
       assertEquals(x.charAt(i+k), z.charAt(k));
     }
   }
 }
-
-
 // Then two-byte strings.
 x = "UC16\u2028";  // Non-ascii char forces two-byte string.
 for (var i = 0; i < 25; i++) {
   x += (i >> 4).toString(16) + (i & 0x0f).toString(16);
 }
 /x/.exec(x);  // Try to force a flatten.
 for (var i = 5; i < 25; i++) {
   for (var j = 0; j < 25; j++) {
     var z = x.substring(i, i + j);
     var w = Math.random() * 42;  // Allocate something new in new-space.
     assertEquals(j, z.length);
     for (var k = 0; k < j; k++) {
       assertEquals(x.charAt(i+k), z.charAt(k));
     }
   }
 }
 
-
 // Keep creating strings to to force allocation failure on substring creation.
 var x = "0123456789ABCDEF";
 x += x;  // 2^5
 x += x;
 x += x;
 x += x;
 x += x;
 x += x;  // 2^10
 x += x;
 x += x;
 var xl = x.length;
 var cache = [];
-for (var i = 0; i < 10000; i++) {
+for (var i = 0; i < 1000; i++) {
   var z = x.substring(i % xl);
   assertEquals(xl - (i % xl), z.length);
   cache.push(z);
 }
 
 
 // Same with two-byte strings
 var x = "\u2028123456789ABCDEF";
 x += x;  // 2^5
 x += x;
 x += x;
 x += x;
 x += x;
 x += x;  // 2^10
 x += x;
 x += x;
 var xl = x.length;
 var cache = [];
-for (var i = 0; i < 10000; i++) {
+for (var i = 0; i < 1000; i++) {
   var z = x.substring(i % xl);
   assertEquals(xl - (i % xl), z.length);
   cache.push(z);
 }
+
+// Substring of substring.
+var cache = [];
+var last = x;
+var offset = 0;
+for (var i = 0; i < 64; i++) {
+  var z = last.substring(i);
+  last = z;
+  cache.push(z);
+  offset += i;
+}
+for (var i = 63; i >= 0; i--) {
+  var z = cache.pop();
+  assertTrue(/\u2028123456789ABCDEF/.test(z));
+  assertEquals(xl - offset, z.length);
+  assertEquals(x.charAt(i*(i+1)/2), z.charAt(0));
+  offset -= i;
+}
+
+// Test charAt for different strings.
+function f(s1, s2, s3, i) {
+  assertEquals(String.fromCharCode(97+i%11), s1.charAt(i%11));
+  assertEquals(String.fromCharCode(97+i%11), s2.charAt(i%11));
+  assertEquals(String.fromCharCode(98+i%11), s3.charAt(i%11));
+  assertEquals(String.fromCharCode(101), s3.charAt(3));
+}
+
+flat = "abcdefghijkl12345";
+cons = flat + flat.toUpperCase();
+slice = "abcdefghijklmn12345".slice(1, -1);
+for ( var i = 0; i < 1000; i++) {
+  f(flat, cons, slice, i);
+}
+flat = "abcdefghijkl1\u20232345";
+cons = flat + flat.toUpperCase();
+slice = "abcdefghijklmn1\u20232345".slice(1, -1);
+for ( var i = 0; i < 1000; i++) {
+  f(flat, cons, slice, i);
+}
+
+// Concatenate substrings.
+var ascii = 'abcdefghijklmnop';
+var utf = '\u03B1\u03B2\u03B3\u03B4\u03B5\u03B6\u03B7\u03B8\u03B9\u03BA\u03BB';
+assertEquals("klmno", ascii.substring(10,15) + ascii.substring(16));
+assertEquals("\u03B4\u03B7", utf.substring(3,4) + utf.substring(6,7));
+assertEquals("klp", ascii.substring(10,12) + ascii.substring(15,16));
+assertEquals("\u03B1\u03B4\u03B5", utf.substring(0,1) + utf.substring(5,3));
+assertEquals("", ascii.substring(16) + utf.substring(16));
+assertEquals("bcdef\u03B4\u03B5\u03B6\u03B7\u03B8\u03B9",
+    ascii.substring(1,6) + utf.substring(3,9));
+assertEquals("\u03B4\u03B5\u03B6\u03B7\u03B8\u03B9abcdefghijklmnop",
+    utf.substring(3,9) + ascii);
+assertEquals("\u03B2\u03B3\u03B4\u03B5\u03B4\u03B5\u03B6\u03B7",
+    utf.substring(5,1) + utf.substring(3,7));
+
+/*
+// Externalizing strings.
+var a = "123456789qwertyuiopasdfghjklzxcvbnm";
+var b = a.slice(1,-1);
+assertEquals(a.slice(1,-1), b);
+externalizeString(a);
+assertEquals(a.slice(1,-1), b);
+*/