consider using something else instead of commander

[boneskull]

there are a couple problems with commander:

• the upgrade from 2.9.x to 2.11.x introduced breaking changes
• we're fiddling with commander's internals in at least one place in bin/_mocha
• no out-of-box support for passing node flags

Ideally whatever module we consume instead should adhere more strictly to semver and allow us to consolidate the executables in bin/.

[Bamieh]

I suggest we look into yargs

[ORESoftware]

dashdash is solid -
https://github.com/trentm/node-dashdash

to pass exec flags, I think it's fine to just to do this:

mocha --exec-flag="--inspect-brk" --exec-flag="--harmony"

maybe not the least verbose tho

also, there is NODE_OPTIONS:

NODE_OPTIONS="--inspect-brk --harmony" mocha

I think NODE_OPTIONS has been backported to Node.js version 6, if I am not mistaken

[boneskull]

NODE_OPTIONS is cool, for sure, but people will complain about environment variables. may be a worth the tradeoff, especially if we couple a solution with #2292

dashdash seems pretty powerful, but I haven't used it. I'm familiar with yargs. Also I think liftoff might help with this sort of thing

[boneskull]

See nodejs/node#17740

[Alhadis]

If a low-level, hands-on approach is needed, you can try get-options. It makes a point of being reliable, explicit, and providing maximal control over argument handling. It's particularly good at handling bundled switches, even those with parameters attached.

The trade-off is that it leaves validation and auto-generated help messages to the author, and doesn't even assume it's running in a Node environment (e.g., it'll work fine in browsers). Naturally, this means no special handling of NODE_OPTIONS, but that can also be parsed into an array _{never mind, I still need to implement that...}

Understandably, the library won't be to everyone's tastes. I wrote it because commander was trying to do too damn MUCH and I coveted something that gave developers more control. But yeah, YMMV.