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 load(libdir + "asserts.js");

 function f(arr)

 {

   assertEq(arr.pop(), undefined); // if it doesn't throw

 }

 var N = 100;

 function basic(out)

 {

   // Create an array of arrays, to be iterated over for [].pop-calling.  We

   // can't just loop on pop on a single array with non-writable length because

   // pop throws when called on an array with non-writable length.

   var arrs = out.arrs = [];

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

   {

     var arr = [0, 1, 2, 3, 4];

     arr.length = 6;

     arrs.push(arr);

   }

   var a = [0, 1, 2, 3, 4];

   Object.defineProperty(a, "length", { writable: false, value: 6 });

   arrs.push(a);

   for (var i = 0, sz = arrs.length; i < sz; i++)

     f(arrs[i]);

 }

 var obj = {};

 var arrs, a;

 assertThrowsInstanceOf(function() { basic(obj); }, TypeError);

 var arrs = obj.arrs;

 assertEq(arrs.length, N + 1);

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

 {

   assertEq(arrs[i].length, 5, "unexpected length for arrs[" + i + "]");

   assertEq(arrs[i].hasOwnProperty(5), false,

            "element not deleted for arrs[" + i + "]");

 }

 var a = arrs[N];

 assertEq(a.hasOwnProperty(5), false);

 assertEq(a[5], undefined);

 assertEq(a.length, 6);