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 load(libdir + "asserts.js");

 function f(arr)

 {

   arr.pop();

 }

 var N = 100;

 function test(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++)

     arrs.push([0, 1, 2, 3]);

   // Use a much-greater capacity than the eventual non-writable length.

   var a = [0, 1, 2, 3, 4, 5, 6, 7];

   Object.defineProperty(a, "length", { writable: false, value: 4 });

   arrs.push(a);

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

     f(arrs[i]);

 }

 var obj = {};

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

 var arrs = obj.arrs;

 assertEq(arrs.length, N + 1);

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

 {

   assertEq(arrs[i].length, 3, "unexpected length for arrs[" + i + "]");

   assertEq(arrs[i][0], 0, "bad element for arrs[" + i + "][0]");

   assertEq(arrs[i][1], 1, "bad element for arrs[" + i + "][1]");

   assertEq(arrs[i][2], 2, "bad element for arrs[" + i + "][2]");

   assertEq(3 in arrs[i], false, "shouldn't be a third element");

   assertEq(arrs[i][3], undefined);

 }

 var a = arrs[N];

 assertEq(a.hasOwnProperty(3), false, "should have been deleted before throw");

 assertEq(a[3], undefined);

 assertEq(a.length, 4, "length shouldn't have been changed");