diff --git a/runtime/JavaScript/spec/rewriter/TokenStreamRewriterSpec.js b/runtime/JavaScript/spec/rewriter/TokenStreamRewriterSpec.js
index a58bc26ef0..022ac0db5f 100644
--- a/runtime/JavaScript/spec/rewriter/TokenStreamRewriterSpec.js
+++ b/runtime/JavaScript/spec/rewriter/TokenStreamRewriterSpec.js
@@ -8,7 +8,7 @@ import calc from "./generatedCode/calc.js";
  * @param {string} input 
  */
 function getRewriter(lexerClass, input) {
-    const chars = new antlr4.InputStream(input);
+    const chars = new antlr4.CharStream(input);
     const lexer = new lexerClass(chars);
     const tokens = new antlr4.CommonTokenStream(lexer);
     tokens.fill();
@@ -385,7 +385,7 @@ describe("TokenStreamRewriter", () => {
     
     it("throws an error if second replace operation overlaps the first one on the left", () => {
         // Arrange
-        const chars = new antlr4.InputStream("abcccba");
+        const chars = new antlr4.CharStream("abcccba");
         const lexer = new abc(chars);
         const tokens = new antlr4.CommonTokenStream(lexer);
         tokens.fill();
diff --git a/runtime/JavaScript/src/antlr4/Lexer.js b/runtime/JavaScript/src/antlr4/Lexer.js
index 0d1a494597..a686976b11 100644
--- a/runtime/JavaScript/src/antlr4/Lexer.js
+++ b/runtime/JavaScript/src/antlr4/Lexer.js
@@ -121,7 +121,9 @@ export default class Lexer extends Recognizer {
 							this.notifyListeners(e); // report error
 							this.recover(e);
 						} else {
-							console.log(e.stack);
+                            if (this._interp.debug) {
+                                console.log(e.stack);
+                            }
 							throw e;
 						}
 					}
diff --git a/runtime/JavaScript/src/antlr4/index.node.js b/runtime/JavaScript/src/antlr4/index.node.js
index 78b55bdb89..4d06196e90 100644
--- a/runtime/JavaScript/src/antlr4/index.node.js
+++ b/runtime/JavaScript/src/antlr4/index.node.js
@@ -14,7 +14,7 @@ import { default as Utils } from './utils/index.js';
 import Token from './Token.js';
 import CommonToken from './CommonToken.js';
 import InputStream from './InputStream.js';
-import CharStream from './InputStream.js';
+import CharStream from './CharStream.js';
 import FileStream from './FileStream.js';
 import CommonTokenStream from './CommonTokenStream.js';
 import Lexer from './Lexer.js';
diff --git a/runtime/JavaScript/src/antlr4/index.web.js b/runtime/JavaScript/src/antlr4/index.web.js
index dec5c91c70..3965b941d1 100644
--- a/runtime/JavaScript/src/antlr4/index.web.js
+++ b/runtime/JavaScript/src/antlr4/index.web.js
@@ -14,7 +14,7 @@ import { default as Utils } from './utils/index.js';
 import Token from './Token.js';
 import CommonToken from './CommonToken.js';
 import InputStream from './InputStream.js';
-import CharStream from './InputStream.js';
+import CharStream from './CharStream.js';
 import CommonTokenStream from './CommonTokenStream.js';
 import Lexer from './Lexer.js';
 import Parser from './Parser.js';