Adding getTokenSource in BufferedTokenStream

runtime/JavaScript/src/antlr4/BufferedTokenStream.js

@@ -260,6 +260,10 @@ BufferedTokenStream.prototype.setTokenSource = function(tokenSource) {
 	this.index = -1;
 };
 
+BufferedTokenStream.prototype.getTokenSource = function() {
+	return this.tokenSource;
+};
+
 // Given a starting index, return the index of the next token on channel.
 // Return i if tokens[i] is on channel. Return -1 if there are no tokens
 // on channel between i and EOF.

runtime/Python2/src/antlr4/BufferedTokenStream.py

@@ -217,7 +217,8 @@ class BufferedTokenStream(TokenStream):
         self.tokens = []
         self.index = -1
 
-
+    def getTokenSource(self):
+        return self.tokenSource
 
     # Given a starting index, return the index of the next token on channel.
     #  Return i if tokens[i] is on channel.  Return -1 if there are no tokens

runtime/Python3/src/antlr4/BufferedTokenStream.py

@@ -220,7 +220,8 @@ class BufferedTokenStream(TokenStream):
         self.tokens = []
         self.index = -1
 
-
+    def getTokenSource(self):
+        return self.tokenSource
 
     # Given a starting index, return the index of the next token on channel.
     #  Return i if tokens[i] is on channel.  Return -1 if there are no tokens