ion-shift-nonwritable-length.js (1669B)
1 function f(arr) 2 { 3 assertEq(arr.shift(), 0); 4 } 5 6 function test(out) 7 { 8 // Create an array of arrays, to be iterated over for [].shift-calling. We 9 // can't just loop on shift on a single array with non-writable length because 10 // shift throws when called on an array with non-writable length. 11 var arrs = out.arrs = []; 12 for (var i = 0; i < 100; i++) 13 arrs.push([0, 1, 2, 3]); 14 15 // Use a much-greater capacity than the eventual non-writable length. 16 var a = [0, 1, 2, 3, 4, 5, 6, 7]; 17 Object.defineProperty(a, "length", { writable: false, value: 4 }); 18 19 arrs.push(a); 20 21 for (var i = 0, sz = arrs.length; i < sz; i++) 22 { 23 var arr = arrs[i]; 24 f(arr); 25 } 26 } 27 28 var obj = {}; 29 var a, arrs; 30 31 try 32 { 33 test(obj); 34 throw new Error("didn't throw!"); 35 } 36 catch (e) 37 { 38 assertEq(e instanceof TypeError, true, "expected TypeError, got " + e); 39 40 arrs = obj.arrs; 41 assertEq(arrs.length, 101); 42 for (var i = 0; i < 100; i++) 43 { 44 assertEq(arrs[i].length, 3, "unexpected length for arrs[" + i + "]"); 45 assertEq(arrs[i][0], 1, "bad element for arrs[" + i + "][0]"); 46 assertEq(arrs[i][1], 2, "bad element for arrs[" + i + "][1]"); 47 assertEq(arrs[i][2], 3, "bad element for arrs[" + i + "][2]"); 48 assertEq(3 in arrs[i], false, "shouldn't be a third element"); 49 assertEq(arrs[i][3], undefined); 50 } 51 52 a = arrs[100]; 53 assertEq(a[0], 1, "bad element for a[" + i + "]"); 54 assertEq(a[1], 2, "bad element for a[" + i + "]"); 55 assertEq(a[2], 3, "bad element for a[" + i + "]"); 56 assertEq(a.hasOwnProperty(3), false, "should have been deleted before throw"); 57 assertEq(a[3], undefined); 58 assertEq(a.length, 4, "length shouldn't have been changed"); 59 }