The Tor Browser / file revision

 /*

  * Any copyright is dedicated to the Public Domain.

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

  * Contributor:

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

  */

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

 var BUGNUMBER = 866700;

 var summary = "Assertion redefining non-writable length to a non-numeric value";

 print(BUGNUMBER + ": " + summary);

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

  * BEGIN TEST *

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

 var arr = [];

 Object.defineProperty(arr, "length", { value: 0, writable: false });

 // Per Array's magical behavior, the value in the descriptor gets canonicalized

 // *before* SameValue comparisons occur, so this shouldn't throw.

 Object.defineProperty(arr, "length", { value: '' });

 assertEq(arr.length, 0);

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

 if (typeof reportCompare === "function")

   reportCompare(true, true);

 print("Tests complete");