1 files changed, 21 insertions, 0 deletions
diff --git a/js/src/tests/test262/language/literals/regexp/invalid-optional-negative-lookbehind.js b/js/src/tests/test262/language/literals/regexp/invalid-optional-negative-lookbehind.js
new file mode 100644
index 0000000000..432227f13e
--- /dev/null
+++ b/js/src/tests/test262/language/literals/regexp/invalid-optional-negative-lookbehind.js
@@ -0,0 +1,21 @@
+// |reftest| error:SyntaxError
+// Copyright (C) 2018 Igalia S. L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-regular-expressions-patterns
+description: Lookbehinds are not treated as a QuantifiableAssertion
+info: |
+    Term[U] ::
+         [~U] QuantifiableAssertion Quantifier
+
+    QuantifiableAssertion[N]::
+        ( ? = Disjunction[~U, ?N] )
+        ( ? ! Disjunction[~U, ?N] )
+negative:
+  phase: parse
+  type: SyntaxError
+---*/
+
+$DONOTEVALUATE();
+
+/.(?<!.)?/;