Lexer is not failing with runtime exception for bad input.

[mehrotraanand]

While upgrading from ANTLR 4.6 to 4.9.2, we have noticed changed in parser behavior and some text which earlier didn't used to be matched gets matched with no change in grammar.

Some Negative input cases are working with lexer
for example

title eq "Emplyee" 1234

I have overridden sytaxError using

lexer.addErrorListener(new BaseErrorListener() {
@OverRide
public void syntaxError(Recognizer recognizer, Object offendingSymbol, int line, int charPositionInLine, String msg, RecognitionException e) {
throw new RuntimeException(e);
}
});
as suggested in
https://stackoverflow.com/questions/29834489/is-it-possible-to-throw-an-exception-if-the-input-isnt-valid?noredirect=1&lq=1

On debugging found that Lexer is not failing with runtime exception for bad input.

We use Java for this implementation.