refactored CommonTokenFactory.js to use es6 classes

fix: dont wrap class in an object for export
use const for better scoping
use jsdoc

runtime/JavaScript/src/antlr4/CommonTokenFactory.js

@@ -1,55 +1,39 @@
-//
 /* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
  * Use of this file is governed by the BSD 3-clause license that
  * can be found in the LICENSE.txt file in the project root.
  */
-//
 
-//
-// This default implementation of {@link TokenFactory} creates
-// {@link CommonToken} objects.
-//
+const CommonToken = require('./Token').CommonToken;
 
-var CommonToken = require('./Token').CommonToken;
+class TokenFactory {}
 
-function TokenFactory() {
-	return this;
-}
-
-function CommonTokenFactory(copyText) {
-	TokenFactory.call(this);
-    // Indicates whether {@link CommonToken//setText} should be called after
-    // constructing tokens to explicitly set the text. This is useful for cases
-    // where the input stream might not be able to provide arbitrary substrings
-    // of text from the input after the lexer creates a token (e.g. the
-    // implementation of {@link CharStream//getText} in
-    // {@link UnbufferedCharStream} throws an
-    // {@link UnsupportedOperationException}). Explicitly setting the token text
-    // allows {@link Token//getText} to be called at any time regardless of the
-    // input stream implementation.
-    //
-    // <p>
-    // The default value is {@code false} to avoid the performance and memory
-    // overhead of copying text for every token unless explicitly requested.</p>
-    //
+/**
+ * This default implementation of {@link TokenFactory} creates
+ * {@link CommonToken} objects.
+ */
+class CommonTokenFactory extends TokenFactory {
+    constructor(copyText) {
+        super();
+        /**
+         * Indicates whether {@link CommonToken//setText} should be called after
+         * constructing tokens to explicitly set the text. This is useful for cases
+         * where the input stream might not be able to provide arbitrary substrings
+         * of text from the input after the lexer creates a token (e.g. the
+         * implementation of {@link CharStream//getText} in
+         * {@link UnbufferedCharStream} throws an
+         * {@link UnsupportedOperationException}). Explicitly setting the token text
+         * allows {@link Token//getText} to be called at any time regardless of the
+         * input stream implementation.
+         *
+         * <p>
+         * The default value is {@code false} to avoid the performance and memory
+         * overhead of copying text for every token unless explicitly requested.</p>
+         */
         this.copyText = copyText===undefined ? false : copyText;
-	return this;
-}
+    }
 
-CommonTokenFactory.prototype = Object.create(TokenFactory.prototype);
-CommonTokenFactory.prototype.constructor = CommonTokenFactory;
-
-//
-// The default {@link CommonTokenFactory} instance.
-//
-// <p>
-// This token factory does not explicitly copy token text when constructing
-// tokens.</p>
-//
-CommonTokenFactory.DEFAULT = new CommonTokenFactory();
-
-CommonTokenFactory.prototype.create = function(source, type, text, channel, start, stop, line, column) {
-    var t = new CommonToken(source, type, channel, start, stop);
+    create(source, type, text, channel, start, stop, line, column) {
+        const t = new CommonToken(source, type, channel, start, stop);
         t.line = line;
         t.column = column;
         if (text !==null) {
@@ -58,12 +42,22 @@ CommonTokenFactory.prototype.create = function(source, type, text, channel, star
             t.text = source[1].getText(start,stop);
         }
         return t;
-};
+    }
 
-CommonTokenFactory.prototype.createThin = function(type, text) {
-    var t = new CommonToken(null, type);
+    createThin(type, text) {
+        const t = new CommonToken(null, type);
         t.text = text;
         return t;
-};
+    }
+}
 
-exports.CommonTokenFactory = CommonTokenFactory;
+/**
+ * The default {@link CommonTokenFactory} instance.
+ *
+ * <p>
+ * This token factory does not explicitly copy token text when constructing
+ * tokens.</p>
+ */
+CommonTokenFactory.DEFAULT = new CommonTokenFactory();
+
+module.exports = CommonTokenFactory;

runtime/JavaScript/src/antlr4/Lexer.js

@@ -10,7 +10,7 @@
 
 var Token = require('./Token').Token;
 var Recognizer = require('./Recognizer').Recognizer;
-var CommonTokenFactory = require('./CommonTokenFactory').CommonTokenFactory;
+var CommonTokenFactory = require('./CommonTokenFactory');
 var RecognitionException  = require('./error/Errors').RecognitionException;
 var LexerNoViableAltException = require('./error/Errors').LexerNoViableAltException;