feat: add eslint to cli project

[astorm]

Adds eslint to CLI project, adjusts existing code to pass eslint rules.

I'm not tied to any particular ruleset, (other than a ruleset that is applied by robots ;)), so suggestions for additional entries to rules: or even extending something other than standard is welcome.

[ghost]

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• Start Time: 2021-12-07T02:51:13.133+0000

• Duration: 7 min 27 sec

• Commit: 8a9b1d1

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[trentm]

Nice. Works for me.

I'm not tied to any particular ruleset

If you wanted to consider prettier, rather than standard for code formatting you are welcome to copy https://github.com/trentm/node-dashdash/blob/master/.eslintrc.json
I think Kibana is using prettier.

But using standard is all good.

(other than a ruleset that is applied by robots ;))

Is that referring to the 'no-control-regex': 0 you have in .eslintrc.js?

My limited understanding is that if one is using stock standard that you could reduce the devDependencies to just "standard": "..." and the "scripts" to:

    "lint": "standard",
    "lint:fix": "standard --fix",

as we have in apm-agent-nodejs.git

[astorm]

(other than a ruleset that is applied by robots ;))
Is that referring to the 'no-control-regex': 0 you have in .eslintrc.js?

Nope, just referring to a general principle that style guidelines that aren't enforced by a program/robot will always end up drifting or being applied inconsistently.