michael@0: // Force recognition of a known-constant.
michael@0: var push = Array.prototype.push;
michael@0: 
michael@0: function f(arr)
michael@0: {
michael@0:   // Push an actual constant to trigger JIT-inlining of the effect of the push.
michael@0:   push.call(arr, 99);
michael@0: }
michael@0: 
michael@0: function basic(out)
michael@0: {
michael@0:   // Create an array of arrays, to be iterated over for [].push-calling.  We
michael@0:   // can't just loop on push on a single array with non-writable length because
michael@0:   // push throws when called on an array with non-writable length.
michael@0:   var arrs = out.arrs = [];
michael@0:   for (var i = 0; i < 100; i++)
michael@0:     arrs.push([]);
michael@0: 
michael@0:   // Use a much-greater capacity than the eventual non-writable length.
michael@0:   var a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15];
michael@0:   Object.defineProperty(a, "length", { writable: false, value: 6 });
michael@0: 
michael@0:   arrs.push(a);
michael@0: 
michael@0:   for (var i = 0, sz = arrs.length; i < sz; i++)
michael@0:   {
michael@0:     var arr = arrs[i];
michael@0:     f(arr);
michael@0:   }
michael@0: }
michael@0: 
michael@0: var obj = {};
michael@0: var arrs, a;
michael@0: 
michael@0: try
michael@0: {
michael@0:   basic(obj);
michael@0:   throw new Error("didn't throw!");
michael@0: }
michael@0: catch (e)
michael@0: {
michael@0:   assertEq(e instanceof TypeError, true, "expected TypeError, got " + e);
michael@0: 
michael@0:   arrs = obj.arrs;
michael@0:   assertEq(arrs.length, 101);
michael@0:   for (var i = 0; i < 100; i++)
michael@0:   {
michael@0:     assertEq(arrs[i].length, 1, "unexpected length for arrs[" + i + "]");
michael@0:     assertEq(arrs[i][0], 99, "bad element for arrs[" + i + "]");
michael@0:   }
michael@0: 
michael@0:   a = arrs[100];
michael@0:   assertEq(a.hasOwnProperty(6), false);
michael@0:   assertEq(a[6], undefined);
michael@0:   assertEq(a.length, 6);
michael@0: }