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Edit File: array-tostring.js
// Copyright 2011 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. // Array's toString should call the object's own join method, if one exists and // is callable. Otherwise, just use the original Object.toString function. var success = "[test success]"; var expectedThis; function testJoin() { assertEquals(0, arguments.length); assertSame(expectedThis, this); return success; } // On an Array object. // Default case. var a1 = [1, 2, 3]; assertEquals(a1.join(), a1.toString()); // Non-standard "join" function is called correctly. var a2 = [1, 2, 3]; a2.join = testJoin; expectedThis = a2; assertEquals(success, a2.toString()); // Non-callable join function is ignored and Object.prototype.toString is // used instead. var a3 = [1, 2, 3]; a3.join = "not callable"; assertEquals("[object Array]", a3.toString()); // Non-existing join function is treated same as non-callable. var a4 = [1, 2, 3]; a4.__proto__ = { toString: Array.prototype.toString }; // No join on Array. assertEquals("[object Array]", a4.toString()); // On a non-Array object. // Default looks-like-an-array case. var o1 = {length: 3, 0: 1, 1: 2, 2: 3, toString: Array.prototype.toString, join: Array.prototype.join}; assertEquals(o1.join(), o1.toString()); // Non-standard join is called correctly. // Check that we don't read, e.g., length before calling join. var o2 = {toString : Array.prototype.toString, join: testJoin, get length() { assertUnreachable(); }, get 0() { assertUnreachable(); }}; expectedThis = o2; assertEquals(success, o2.toString()); // Non-standard join is called even if it looks like an array. var o3 = {length: 3, 0: 1, 1: 2, 2: 3, toString: Array.prototype.toString, join: testJoin}; expectedThis = o3; assertEquals(success, o3.toString()); // Non-callable join works same as for Array. var o4 = {length: 3, 0: 1, 1: 2, 2: 3, toString: Array.prototype.toString, join: "not callable"}; assertEquals("[object Object]", o4.toString()); // Non-existing join works same as for Array. var o5 = {length: 3, 0: 1, 1: 2, 2: 3, toString: Array.prototype.toString /* no join */}; assertEquals("[object Object]", o5.toString()); // Test that ToObject is called before getting "join", so the instance // that "join" is read from is the same one passed as receiver later. var called_before = false; expectedThis = null; Object.defineProperty(Number.prototype, "join", {get: function() { assertFalse(called_before); called_before = true; expectedThis = this; return testJoin; }}); Number.prototype.arrayToString = Array.prototype.toString; assertEquals(success, (42).arrayToString()); // ---------------------------------------------------------- // Testing Array.prototype.toLocaleString // Ensure that it never uses Array.prototype.toString for anything. Array.prototype.toString = function() { assertUnreachable(); }; // Default case. var la1 = [1, [2, 3], 4]; assertEquals("1,2,3,4", la1.toLocaleString()); // Used on a string (which looks like an array of characters). String.prototype.toLocaleString = Array.prototype.toLocaleString; assertEquals("1,2,3,4", "1234".toLocaleString()); // If toLocaleString of element is not callable, throw a TypeError. var la2 = [1, {toLocaleString: "not callable"}, 3]; assertThrows(function() { la2.toLocaleString(); }, TypeError); // If toLocaleString of element is callable, call it. var la3 = [1, {toLocaleString: function() { return "XX";}}, 3]; assertEquals("1,XX,3", la3.toLocaleString()); // Omitted elements, as well as undefined and null, become empty string. var la4 = [1, null, 3, undefined, 5,, 7]; assertEquals("1,,3,,5,,7", la4.toLocaleString()); // ToObject is called first and the same object is being used for the // rest of the operations. Object.defineProperty(Number.prototype, "length", { get: function() { exptectedThis = this; return 3; }}); for (var i = 0; i < 3; i++) { Object.defineProperty(Number.prototype, i, { get: function() { assertEquals(expectedThis, this); return +this; }}); } Number.prototype.arrayToLocaleString = Array.prototype.toLocaleString; assertEquals("42,42,42", (42).arrayToLocaleString());