join-01.js - mozsearch

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/*

 * Any copyright is dedicated to the Public Domain.

 * http://creativecommons.org/licenses/publicdomain/

 * Contributor:

 *   Jeff Walden <jwalden+code@mit.edu>

*/

//-----------------------------------------------------------------------------

print("ES5: Array.prototype.join");

/**************

 * BEGIN TEST *

 **************/

var count;

var stringifyCounter = { toString: function() { count++; return "obj"; } };

var arr = [1, 2, 3, 4, 5];

assertEq(arr.join(), "1,2,3,4,5");

assertEq(arr.join(","), "1,2,3,4,5");

assertEq(arr.join(undefined), "1,2,3,4,5");

assertEq(arr.join(4), "142434445");

assertEq(arr.join(""), "12345");

count = 0;

assertEq(arr.join(stringifyCounter), "1obj2obj3obj4obj5");

assertEq(count, 1);

var holey = [1, 2, , 4, 5];

assertEq(holey.join(), "1,2,,4,5");

assertEq(holey.join(","), "1,2,,4,5");

assertEq(holey.join(undefined), "1,2,,4,5");

assertEq(holey.join(4), "14244445");

count = 0;

assertEq(holey.join(stringifyCounter), "1obj2objobj4obj5");

assertEq(count, 1);

var nully = [1, 2, 3, null, 5];

assertEq(nully.join(), "1,2,3,,5");

assertEq(nully.join(","), "1,2,3,,5");

assertEq(nully.join(undefined), "1,2,3,,5");

assertEq(nully.join(4), "14243445");

count = 0;

assertEq(nully.join(stringifyCounter), "1obj2obj3objobj5");

assertEq(count, 1);

var undefiney = [1, undefined, 3, 4, 5];

assertEq(undefiney.join(), "1,,3,4,5");

assertEq(undefiney.join(","), "1,,3,4,5");

assertEq(undefiney.join(undefined), "1,,3,4,5");

assertEq(undefiney.join(4), "14434445");

count = 0;

assertEq(undefiney.join(stringifyCounter), "1objobj3obj4obj5");

assertEq(count, 1);

var log = '';

arr = {length: {valueOf: function () { log += "L"; return 2; }},

      0: "x", 1: "z"};

var sep = {toString: function () { log += "S"; return "y"; }};

assertEq(Array.prototype.join.call(arr, sep), "xyz");

assertEq(log, "LS");

var funky =

    toString: function()

      Array.prototype[1] = "chorp";

      Object.prototype[3] = "fnord";

      return "funky";

};

var trailingHoles = [0, funky, /* 2 */, /* 3 */,];

assertEq(trailingHoles.join(""), "0funkyfnord");

/******************************************************************************/

if (typeof reportCompare === "function")

  reportCompare(true, true);

print("Tests complete");