dart compile jit-snapshot can't take flags (like -o) or --options as training arguments

[cpswan]

Dart SDK version: 2.17.3 (stable) (Wed Jun 1 11:06:41 2022 +0200) on "linux_x64"

If I try to pass an option -e as [<training arguments>]:

$ dart compile jit-snapshot args_example.dart -e 1234
Could not find an option or flag "-e".

Usage: dart compile jit-snapshot [arguments] <dart entry point> [<training arguments>]
...

or similarly --example:

$ dart compile jit-snapshot args_example.dart --example 1234
Could not find an option named "example".
...

Where args_example.dart is:

import 'package:args/args.dart';

void main(List<String> arguments) {

  final parser = ArgParser()..addOption('example', abbr: 'e');

  ArgResults argResults = parser.parse(arguments);
  
  print(argResults['example']);
  
}

It looks like this area has previously had attention for arguments that aren't preceded by - at #43839 and for env variables with #48447

[bkonyi]

Fix up for review here.

[cpswan]

@bkonyi do you know which SDK release this will find its way into? As 2.17.5 and 2.17.6 have been released since this was closed I was hopeful that they'd have the fix, but it seems not.

[mraleph]

@cpswan it in 2.18.0-226.0.dev or newer.