@Override
			public void syntaxError(Recognizer<?, ?> recognizer, Object offendingSymbol, int line, int charPositionInLine, String msg, RecognitionException e) {
				errors.add("line " + line + ":" + charPositionInLine + " " + msg);
			}
This test verifies the basic behavior of visitors, with an emphasis on
{@link AbstractParseTreeVisitor#visitErrorNode}.
runtime-testsuite/test/org/antlr/v4/test/runtime/java/api/TestVisitors.java