Make a few exceptions to the standard rules

[zeke]

The standard linter has a few rules that feel restrictive when applied to javascript blocks in markdown files. While standardizing electron's docs, these are the rules I came across that I think we could do without:

Disallow Undeclared Variables (no-undef)

// `win` is not declared in this block
win.close()

Disallow Unused Variables (no-unused-vars)

// `BrowserWindow` is declared but not used
const {BrowserWindow} = require('electron')

Disallow Unnecessary Nested Blocks (no-lone-blocks, no-labels)

Example electron/electron#6748

// this object is just dangling in space
{
  marginsType: 0,
  printBackground: false
}

How?

I think the way to accomplish this is by forking eslint-config-standard, then using standard-engine to load it. We can use the numerous standard forks for reference.

@ferros, @Flet: If we only wish to deviate very slightly from standard's defaults, is there a way to codify the differences in a package.json stanza? Or is standard-engine with a custom eslint package the way to go?

cc @kevinsawicki @jlord @zcbenz

[MarshallOfSound]

@zeke So we don't have to fork things crazily. Couldn't we "hack" in eslint disable comments to the JS blocks we are parsing.

I.e. We have a code block block

const disabledRules = ['no-undef', 'no-unused-vars', 'no-lone-blocks', 'no-labels'];
let block = getCodeBlockThing();
block = `
/* eslint-disable ${disabledRules.join(', ')} */
` + block;
standard.lintText(block)

This is untested, just an idea 😄

[feross]

I didn't see this until now because you misspelled my name, @zeke 😜

Disabling these rules makes standard-readme way more useful -- good call! They're the reason I haven't adopted it on my projects yet.

@MarshallOfSound's suggesting is the best solution IMO. It's easiest and easy to maintain -- will have the exact same rules, dependency versions, etc. as the latest stable standard.

---

Another option, but less ideal, is to extend standard to layer your rule changes on top. No need to fork eslint-config-standard to do this.

You can make a eslintrc.json file like this one:

{
  "extends": ["standard", "standard-jsx"],
  "rules": {
    "no-undef": 0,
    "no-unused-vars": 0
  }
}

Install all the standard dependencies. Then use the eslintrc.json with standard-engine.

One big downside is now it's your responsibility to ensure that the package versions are kept up-to-date and match what's in standard. You can try just always using the latest versions with * and it will probably work fine. But there are some situations when ESLint has a bug where we hold back the semver range to an older version until it's fixed. So you lose that with this approach.

[zeke]

I didn't see this until now because you misspelled my name

Doh! I do know how to spell it. I blame my fingers. 🖖

[zeke]

#3 and #6 landed in 1.2.0 🚀

Thanks for the help, @MarshallOfSound and @feross!