void () { final RegExpLexer lexer = new RegExpLexer(EnumSet.of(OCTAL_NO_LEADING_ZERO)); doTest("\\0()\\0[\\0]", """ OCT_CHAR ('\\0') GROUP_BEGIN ('(') GROUP_END (')') OCT_CHAR ('\\0') CLASS_BEGIN ('[') OCT_CHAR ('\\0') CLASS_END (']')""", lexer); }