Remove deprecated key 'root' from node's env

[eight04]

Tell us about your environment

• ESLint Version: 4.5.0
• Node Version: 7.9.0
• npm Version: 5.3.0

What parser (default, Babel-ESLint, etc.) are you using?
default

Please show your full configuration:

Configuration

eslint --no-eslintrc --env es6,node --rule "no-undef: 2" test.js

What did you do? Please include the actual source code causing the issue.

class Test {
	constructor(root) {
		this.root = root;
	}
	doSomething() {
		console.log(`${root}`);
	}
}

What did you expect to happen?

  6:18  error  'root' is not defined     no-undef

What actually happened? Please include the actual, raw output from ESLint.
Nothing is reported, because root is a global variable in node env.

However, global root is a deprecated feature. By removing root from node's env, it should help those developers that accidentally access global root variable.

[kaicataldo]

Unfortunately, ESLint can't make any assumptions about which version of Node someone is using. This is the package we use: https://github.com/sindresorhus/globals/blob/master/globals.json#L867

There are third party plugins such as https://www.npmjs.com/package/eslint-plugin-node that will actually do feature-checking based on the Node version, and something like that could be a good place for a feature like this.

Alternatively, are you suggesting that ESLint should be enhanced to allow specification of the target Node version? That's an interesting thought, though it's not a trivial thing to implement.

[eight04]

It seems that this issue should be moved to https://github.com/sindresorhus/globals.

I understand those platform-specified rules should be handled by plugins. However, I don't know if env global is in this case. Are those globals maintained by ESLint team? For example, Greasemonkey is working on version 4.0 which might add/remove some globals too (greasemonkey/greasemonkey#2484).

BTW, https://github.com/mysticatea/eslint-plugin-node looks good. I'll definitely try it.

[eight04]

NVM, I saw that those are located in globals.json.
https://github.com/sindresorhus/globals/blob/890bcfe6e052739ce2d4dea038589f9243cf9b17/globals.json#L1277

[platinumazure]

@eight04 By the way, you could use no-restricted-globals to enforce that root is not used as a global in your code.