1 files changed, 27 insertions, 0 deletions
diff --git a/js/src/tests/test262/language/literals/string/legacy-non-octal-escape-sequence-5-strict-explicit-pragma.js b/js/src/tests/test262/language/literals/string/legacy-non-octal-escape-sequence-5-strict-explicit-pragma.js
new file mode 100644
index 0000000000..a5bed9e50b
--- /dev/null
+++ b/js/src/tests/test262/language/literals/string/legacy-non-octal-escape-sequence-5-strict-explicit-pragma.js
@@ -0,0 +1,27 @@
+// |reftest| error:SyntaxError
+// Copyright (C) 2020 Rick Waldron Inc. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-literals-string-literals
+description: >
+  String Literals extensions disallowed in strict mode; FourToSeven 5
+info: |
+  It is possible for string literals to precede a Use Strict Directive that places the enclosing
+  code in strict mode, and implementations must take care to not use this extended definition of
+  EscapeSequence with such literals. For example, attempting to parse the following source text
+  must fail.
+
+  Strict mode is entered via the explicit Use Strict Directive.
+
+  FourToSeven::one of
+    4 5 6 7
+
+flags: [noStrict]
+negative:
+  phase: parse
+  type: SyntaxError
+---*/
+
+$DONOTEVALUATE();
+
+function invalid() { "\5"; "use strict"; }