diff -r 000000000000 -r 6474c204b198 js/src/tests/ecma_5/extensions/8.12.5-01.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/ecma_5/extensions/8.12.5-01.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,97 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/*
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/licenses/publicdomain/
+ * Contributor:
+ *   Jason Orendorff
+ *   Jeff Walden <jwalden+code@mit.edu>
+ */
+
+//-----------------------------------------------------------------------------
+var BUGNUMBER = 523846;
+var summary =
+  "Assignments to a property that has a getter but not a setter should not " +
+  "throw a TypeError per ES5 (at least not until strict mode is supported)";
+var actual = "Early failure";
+var expect = "No errors";
+
+
+printBugNumber(BUGNUMBER);
+printStatus(summary);
+
+var o = { get p() { return "a"; } };
+
+function test1()
+{
+  o.p = "b"; // strict-mode violation here
+  assertEq(o.p, "a");
+}
+
+function test2()
+{
+  function T() {}
+  T.prototype = o;
+  y = new T();
+  y.p = "b";  // strict-mode violation here
+  assertEq(y.p, "a");
+}
+
+
+var errors = [];
+try
+{
+  try
+  {
+    test1();
+  }
+  catch (e)
+  {
+    errors.push(e);
+  }
+
+  try
+  {
+    test2();
+  }
+  catch (e)
+  {
+    errors.push(e);
+  }
+
+  options("strict");
+  options("werror");
+  try
+  {
+    test1();
+    errors.push("strict+werror didn't make test1 fail");
+  }
+  catch (e)
+  {
+    if (!(e instanceof TypeError))
+      errors.push("test1 with strict+werror failed without a TypeError: " + e);
+  }
+
+  try
+  {
+    test2();
+    errors.push("strict+werror didn't make test2 fail");
+  }
+  catch (e)
+  {
+    if (!(e instanceof TypeError))
+      errors.push("test2 with strict+werror failed without a TypeError: " + e);
+  }
+
+  options("strict");
+  options("werror");
+}
+catch (e)
+{
+  errors.push("Unexpected error: " + e);
+}
+finally
+{
+  actual = errors.length > 0 ? errors.join(", ") : "No errors";
+}
+
+reportCompare(expect, actual, summary);