1 files changed, 52 insertions, 0 deletions
diff --git a/js/src/tests/non262/regress/regress-383674.js b/js/src/tests/non262/regress/regress-383674.js
new file mode 100644
index 0000000000..293d8a556d
--- /dev/null
+++ b/js/src/tests/non262/regress/regress-383674.js
@@ -0,0 +1,52 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//-----------------------------------------------------------------------------
+var BUGNUMBER = 383674;
+var summary = 'Statement that implicitly calls toString should not be optimized away as a "useless expression"';
+var actual = '';
+var expect = '';
+
+
+//-----------------------------------------------------------------------------
+test();
+//-----------------------------------------------------------------------------
+
+function test()
+{
+  printBugNumber(BUGNUMBER);
+  printStatus (summary);
+
+  expect = 'toString called';
+  actual = 'toString not called';
+  try
+  {
+    var x = {toString: function() {
+        actual = 'toString called';
+        print(actual);
+      }
+    };
+    var f = function() { var j = x; j + ""; }
+    f();
+    reportCompare(expect, actual, summary + ': 1');
+  }
+  catch(ex)
+  {
+    reportCompare("No Error", ex + "", summary + ': 1');
+  }
+
+  actual = 'toString not called';
+  try
+  {
+    (function() { var a =
+         ({toString: function(){
+             actual = 'toString called'; print(actual)} }); a += ""; })();
+    reportCompare(expect, actual, summary + ': 2');
+  }
+  catch(ex)
+  {
+    reportCompare("No Error", ex + "", summary + ': 2');
+  }
+}