ANTLR4 Unicode Parse Not Recognized by grun - antlr

Question

Given the following:
grammar Lang
start: CHAR;
CHAR: [\uE001];
WS: [ \t\r\n]+ -> skip;
When this batch file runs:
#echo off
setlocal
call antlr4 -o .\javatarget LangFile.g4 -encoding UTF-8
cd .\javatarget
call javac LangFile*.java
call grun LangFile Lang -gui -diagnostics -trace -encoding UTF-8
endlocal
#echo on
This error happens when I paste in the Unicode character:

^Z
line 1:0 token recognition error at: '?'
enter Lang, LT(1)=<EOF>
consume [#0,3:2='<EOF>',<-1>,2:0] rule Lang
exit Lang, LT(1)=<EOF>
Despite my search into the other answers (such as the -encoding option), I cannot seem to get this kind of Unicode (the Private Use Areas) parsing to work.
Edit: I have version 4.8.
The problem seems to be with the grun tool. Running it manually with Python runs fine, and so does specifying an input file. But directly pasting the content into the console fails. It's good enough for me to revert to using an input file, but perhaps this question is answered when grun's direct input mode works.

Answer 1

Could be an issue with how your grun script handles the input, because when I generate a lexer and parser and run this:
LangLexer lexer = new LangLexer(CharStreams.fromString("\uE001"));
LangParser parser = new LangParser(new CommonTokenStream(lexer));
parser.start();
it parses without any warnings or errors.