ownkeys-linear.js - mozsearch

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/*

 * Any copyright is dedicated to the Public Domain.

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

*/

var gTestfile = 'ownkeys-linear.js';

var BUGNUMBER = 1257779;

var summary =

  "Scripted proxies' [[OwnPropertyKeys]] should have linear complexity";

print(BUGNUMBER + ": " + summary);

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

 * BEGIN TEST *

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

// Making this 50k makes cgc builds time out on tbpl.  5k takes 28s locally.

// 10k takes 84s locally.  So pick an intermediate number, with a generous

// constant factor in case cgc-on-tbpl is much slower.

const HALF_COUNT = 7500;

var configurables = [];

for (var i = 0; i < HALF_COUNT; i++)

  configurables.push("conf" + i);

var nonconfigurables = [];

for (var i = 0; i < HALF_COUNT; i++)

  nonconfigurables.push("nonconf" + i);

var target = {};

for (var name of configurables)

  Object.defineProperty(target, name, { configurable: false, value: 0 });

for (var name of nonconfigurables)

  Object.defineProperty(target, name, { configurable: true, value:  0 });

var handler = {

  ownKeys(t) {

    assertEq(t, target, "target mismatch!");

    var trapResult = [];

    // Append all nonconfigurables in reverse order of presence.

    for (var i = nonconfigurables.length; i > 0; i--)

      trapResult.push(nonconfigurables[i - 1]);

    // Then the same for all configurables.

    for (var i = configurables.length; i > 0; i--)

      trapResult.push(configurables[i - 1]);

    // The end consequence is that this ordering is exactly opposite the

    // ordering they'll have on the target, and so worst-case performance will

    // occur if the spec's |uncheckedResultKeys| structure is a vector having

    // the same order as |trapResult|, searched from beginning to end in the

    // presence-checks in the last few steps of the [[OwnPropertyKeys]]

    // algorithm.

    return trapResult;

};

var p = new Proxy(target, handler);

// The test passes if it doesn't time out.

assertEq(Object.getOwnPropertyNames(p).length, HALF_COUNT * 2);

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

if (typeof reportCompare === "function")

  reportCompare(true, true);

print("Tests complete");