JezK
Edit File: string-charat.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. var s = "test"; function getTwoByteString() { return "\u1234t"; } function getCons() { return "testtesttesttest" + getTwoByteString() } var slowIndex1 = { valueOf: function() { return 1; } }; var slowIndex2 = { toString: function() { return "2"; } }; var slowIndexOutOfRange = { valueOf: function() { return -1; } }; function basicTest(s, len) { assertEquals("t", s().charAt()); assertEquals("t", s().charAt("string")); assertEquals("t", s().charAt(null)); assertEquals("t", s().charAt(void 0)); assertEquals("t", s().charAt(false)); assertEquals("e", s().charAt(true)); assertEquals("", s().charAt(-1)); assertEquals("", s().charAt(len)); assertEquals("", s().charAt(slowIndexOutOfRange)); assertEquals("", s().charAt(1/0)); assertEquals("", s().charAt(-1/0)); assertEquals("t", s().charAt(0)); assertEquals("t", s().charAt(-0.0)); assertEquals("t", s().charAt(-0.1)); assertEquals("t", s().charAt(0.4)); assertEquals("e", s().charAt(slowIndex1)); assertEquals("s", s().charAt(slowIndex2)); assertEquals("t", s().charAt(3)); assertEquals("t", s().charAt(3.4)); assertEquals("t", s().charAt(NaN)); assertEquals(116, s().charCodeAt()); assertEquals(116, s().charCodeAt("string")); assertEquals(116, s().charCodeAt(null)); assertEquals(116, s().charCodeAt(void 0)); assertEquals(116, s().charCodeAt(false)); assertEquals(101, s().charCodeAt(true)); assertEquals(116, s().charCodeAt(0)); assertEquals(116, s().charCodeAt(-0.0)); assertEquals(116, s().charCodeAt(-0.1)); assertEquals(116, s().charCodeAt(0.4)); assertEquals(101, s().charCodeAt(slowIndex1)); assertEquals(115, s().charCodeAt(slowIndex2)); assertEquals(116, s().charCodeAt(3)); assertEquals(116, s().charCodeAt(3.4)); assertEquals(116, s().charCodeAt(NaN)); assertTrue(isNaN(s().charCodeAt(-1))); assertTrue(isNaN(s().charCodeAt(len))); assertTrue(isNaN(s().charCodeAt(slowIndexOutOfRange))); assertTrue(isNaN(s().charCodeAt(1/0))); assertTrue(isNaN(s().charCodeAt(-1/0))); } basicTest(function() { return s; }, s.length); basicTest(getCons, getCons().length); // Make sure enough of the one-char string cache is filled. var alpha = ['@']; for (var i = 1; i < 128; i++) { var c = String.fromCharCode(i); alpha[i] = c.charAt(0); } var alphaStr = alpha.join(""); // Now test chars. for (var i = 1; i < 128; i++) { assertEquals(alpha[i], alphaStr.charAt(i)); assertEquals(String.fromCharCode(i), alphaStr.charAt(i)); } // Test stealing String.prototype.{charAt,charCodeAt}. var o = { charAt: String.prototype.charAt, charCodeAt: String.prototype.charCodeAt, toString: function() { return "012"; }, valueOf: function() { return "should not be called"; } }; function stealTest() { assertEquals("0", o.charAt(0)); assertEquals("1", o.charAt(1)); assertEquals("1", o.charAt(1.4)); assertEquals("1", o.charAt(slowIndex1)); assertEquals("2", o.charAt(2)); assertEquals("2", o.charAt(slowIndex2)); assertEquals(48, o.charCodeAt(0)); assertEquals(49, o.charCodeAt(1)); assertEquals(49, o.charCodeAt(1.4)); assertEquals(49, o.charCodeAt(slowIndex1)); assertEquals(50, o.charCodeAt(2)); assertEquals(50, o.charCodeAt(slowIndex2)); assertEquals("", o.charAt(-1)); assertEquals("", o.charAt(-1.4)); assertEquals("", o.charAt(10)); assertEquals("", o.charAt(slowIndexOutOfRange)); assertTrue(isNaN(o.charCodeAt(-1))); assertTrue(isNaN(o.charCodeAt(-1.4))); assertTrue(isNaN(o.charCodeAt(10))); assertTrue(isNaN(o.charCodeAt(slowIndexOutOfRange))); } stealTest(); // Test custom string IC-s. for (var i = 0; i < 20; i++) { basicTest(function() { return s; }, s.length); basicTest(getCons, getCons().length); stealTest(); } var badToString = function() { return []; }; function testBadToString_charAt() { var goodToString = o.toString; var hasCaught = false; var numCalls = 0; var result; try { for (var i = 0; i < 20; i++) { if (i == 10) o.toString = o.valueOf = badToString; result = o.charAt(1); numCalls++; } } catch (e) { hasCaught = true; } finally { o.toString = goodToString; } assertTrue(hasCaught); assertEquals("1", result); assertEquals(10, numCalls); } testBadToString_charAt(); function testBadToString_charCodeAt() { var goodToString = o.toString; var hasCaught = false; var numCalls = 0; var result; try { for (var i = 0; i < 20; i++) { if (i == 10) o.toString = o.valueOf = badToString; result = o.charCodeAt(1); numCalls++; } } catch (e) { hasCaught = true; } finally { o.toString = goodToString; } assertTrue(hasCaught); assertEquals(49, result); assertEquals(10, numCalls); } testBadToString_charCodeAt(); var badIndex = { toString: badToString, valueOf: badToString }; function testBadIndex_charAt() { var index = 1; var hasCaught = false; var numCalls = 0; var result; try { for (var i = 0; i < 20; i++) { if (i == 10) index = badIndex; result = o.charAt(index); numCalls++; } } catch (e) { hasCaught = true; } assertTrue(hasCaught); assertEquals("1", result); assertEquals(10, numCalls); } testBadIndex_charAt(); function testBadIndex_charCodeAt() { var index = 1; var hasCaught = false; var numCalls = 0; var result; try { for (var i = 0; i < 20; i++) { if (i == 10) index = badIndex; result = o.charCodeAt(index); numCalls++; } } catch (e) { hasCaught = true; } assertTrue(hasCaught); assertEquals(49, result); assertEquals(10, numCalls); } testBadIndex_charCodeAt(); function testPrototypeChange_charAt() { var result, oldResult; for (var i = 0; i < 20; i++) { if (i == 10) { oldResult = result; String.prototype.charAt = function() { return "%"; }; } result = s.charAt(1); } assertEquals("%", result); assertEquals("e", oldResult); delete String.prototype.charAt; // Restore the default. } testPrototypeChange_charAt(); function testPrototypeChange_charCodeAt() { var result, oldResult; for (var i = 0; i < 20; i++) { if (i == 10) { oldResult = result; String.prototype.charCodeAt = function() { return 42; }; } result = s.charCodeAt(1); } assertEquals(42, result); assertEquals(101, oldResult); delete String.prototype.charCodeAt; // Restore the default. } testPrototypeChange_charCodeAt();