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 function f(arr, v)

 {

   arr.push(v);

 }

 function basic(out)

 {

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

   var a = out.a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15];

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

   f(a, 99);

 }

 var obj = {};

 var a;

 try

 {

   basic(obj);

   throw new Error("didn't throw!");

 }

 catch (e)

 {

   assertEq(e instanceof TypeError, true, "expected TypeError, got " + e);

   a = obj.a;

   assertEq(a.hasOwnProperty(6), false);

   assertEq(a[6], undefined);

   assertEq(a.length, 6);

 }