From 53220f25fe2c51c3d4fb97de4287d2c97677c673 Mon Sep 17 00:00:00 2001
From: Pete Gonzalez <4673363+octogonz@users.noreply.github.com>
Date: Tue, 19 Jan 2021 21:53:38 -0800
Subject: [PATCH] Fix for incompatibility with the TypeScript transpiler
 (GitHub issue #3032)

---
 runtime/JavaScript/src/antlr4/error/Errors.js | 39 ++++++++++++++++++-
 runtime/JavaScript/src/antlr4/error/index.js  |  1 +
 2 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/runtime/JavaScript/src/antlr4/error/Errors.js b/runtime/JavaScript/src/antlr4/error/Errors.js
index 1308e9e5e20..ed0a7c6055d 100644
--- a/runtime/JavaScript/src/antlr4/error/Errors.js
+++ b/runtime/JavaScript/src/antlr4/error/Errors.js
@@ -13,7 +13,42 @@
 
 const {PredicateTransition} = require('./../atn/Transition')
 
-class RecognitionException extends Error {
+/**
+ * The base class for error classes.  This is used instead of the system Error class to avoid
+ * incompatibilities with transpilers targeting ECMASCript 5.
+ */
+class AntlrError {
+    constructor(message) {
+        const systemError = new Error(message)
+        this.name = systemError.name;
+        this.message = systemError.message;
+        this.stack = systemError.stack;
+    }
+
+    toString() {
+        var obj = Object(this);
+        if (obj !== this) {
+          throw new TypeError();
+        }
+
+        var name = this.name;
+        name = (name === undefined) ? 'Error' : String(name);
+
+        var msg = this.message;
+        msg = (msg === undefined) ? '' : String(msg);
+
+        if (name === '') {
+          return msg;
+        }
+        if (msg === '') {
+          return name;
+        }
+
+        return name + ': ' + msg;
+    }
+}
+
+class RecognitionException extends AntlrError {
     constructor(params) {
         super(params.message);
         if (!!Error.captureStackTrace) {
@@ -156,7 +191,7 @@ class FailedPredicateException extends RecognitionException {
 }
 
 
-class ParseCancellationException extends Error{
+class ParseCancellationException extends AntlrError {
     constructor() {
         super()
         Error.captureStackTrace(this, ParseCancellationException);
diff --git a/runtime/JavaScript/src/antlr4/error/index.js b/runtime/JavaScript/src/antlr4/error/index.js
index 482b47edbed..61e89c8245a 100644
--- a/runtime/JavaScript/src/antlr4/error/index.js
+++ b/runtime/JavaScript/src/antlr4/error/index.js
@@ -3,6 +3,7 @@
  * can be found in the LICENSE.txt file in the project root.
  */
 
+module.exports.AntlrError = require('./Errors').AntlrError;
 module.exports.RecognitionException = require('./Errors').RecognitionException;
 module.exports.NoViableAltException = require('./Errors').NoViableAltException;
 module.exports.LexerNoViableAltException = require('./Errors').LexerNoViableAltException;