From 668c4a382f1919d13772d2d66fbea75e9c6b3b3b Mon Sep 17 00:00:00 2001
From: Mike Pennisi <mike@mikepennisi.com>
Date: Wed, 6 Feb 2019 21:42:59 -0500
Subject: [PATCH] [[FIX]] Correct parsing of RegExp character sets

Do not interpret RegExp syntax characters using their specialized
semantics when they appear within a character set.
---
 src/lex.js           | 5 +++++
 tests/unit/parser.js | 6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/src/lex.js b/src/lex.js
index 1ea296ae9e..1b1540c7e9 100644
--- a/src/lex.js
+++ b/src/lex.js
@@ -1582,6 +1582,11 @@ Lexer.prototype = {
         continue;
       }
 
+      if (isCharSet) {
+        index += 1;
+        continue;
+      }
+
       if (char === "{" && !hasInvalidQuantifier) {
         hasInvalidQuantifier = !checkQuantifier();
       }
diff --git a/tests/unit/parser.js b/tests/unit/parser.js
index c5e049b198..10efb3a2cd 100644
--- a/tests/unit/parser.js
+++ b/tests/unit/parser.js
@@ -866,6 +866,12 @@ exports.regexp.regressions = function (test) {
   TestRun(test).test("var exp = /\\[\\]/;", {esnext: true});
   TestRun(test).test("var exp = /\\[\\]/;", {moz: true});
 
+  // GH-3356
+  TestRun(test).test("void /[/]/;");
+  TestRun(test).test("void /[{]/u;", {esversion: 6});
+  TestRun(test).test("void /[(?=)*]/u;", {esversion: 6});
+  TestRun(test).test("void /[(?!)+]/u;", {esversion: 6});
+
   test.done();
 };