[notes]
This is a regression test for #6 "NullPointerException in getMissingSymbol".
https://github.com/antlr/antlr4/issues/6

[type]
Parser

[grammar]
grammar T;
start : ID+;
ID : [a-z]+;

[start]
start

[input]


[errors]
"""line 1:0 mismatched input '<EOF>' expecting ID
"""