1 files changed, 56 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/arrays/push-densely-loopy-nonwritable-length.js b/js/src/jit-test/tests/arrays/push-densely-loopy-nonwritable-length.js
new file mode 100644
index 0000000000..e09ed09645
--- /dev/null
+++ b/js/src/jit-test/tests/arrays/push-densely-loopy-nonwritable-length.js
@@ -0,0 +1,56 @@
+// Force recognition of a known-constant.
+var push = Array.prototype.push;
+
+function f(arr)
+{
+  // Push an actual constant to trigger JIT-inlining of the effect of the push.
+  push.call(arr, 99);
+}
+
+function basic(out)
+{
+  // Create an array of arrays, to be iterated over for [].push-calling.  We
+  // can't just loop on push on a single array with non-writable length because
+  // push throws when called on an array with non-writable length.
+  var arrs = out.arrs = [];
+  for (var i = 0; i < 100; i++)
+    arrs.push([]);
+
+  // Use a much-greater capacity than the eventual non-writable length.
+  var 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 });
+
+  arrs.push(a);
+
+  for (var i = 0, sz = arrs.length; i < sz; i++)
+  {
+    var arr = arrs[i];
+    f(arr);
+  }
+}
+
+var obj = {};
+var arrs, a;
+
+try
+{
+  basic(obj);
+  throw new Error("didn't throw!");
+}
+catch (e)
+{
+  assertEq(e instanceof TypeError, true, "expected TypeError, got " + e);
+
+  arrs = obj.arrs;
+  assertEq(arrs.length, 101);
+  for (var i = 0; i < 100; i++)
+  {
+    assertEq(arrs[i].length, 1, "unexpected length for arrs[" + i + "]");
+    assertEq(arrs[i][0], 99, "bad element for arrs[" + i + "]");
+  }
+
+  a = arrs[100];
+  assertEq(a.hasOwnProperty(6), false);
+  assertEq(a[6], undefined);
+  assertEq(a.length, 6);
+}